1.
Edinburgh
–
Edinburgh is the capital city of Scotland and one of its 32 local government council areas. Located in Lothian on the Firth of Forths southern shore, it is Scotlands second most populous city and the seventh most populous in the United Kingdom. The 2014 official population estimates are 464,990 for the city of Edinburgh,492,680 for the authority area. Recognised as the capital of Scotland since at least the 15th century, Edinburgh is home to the Scottish Parliament and it is the largest financial centre in the UK after London. Historically part of Midlothian, the city has long been a centre of education, particularly in the fields of medicine, Scots law, literature, the sciences and engineering. The University of Edinburgh, founded in 1582 and now one of four in the city, was placed 17th in the QS World University Rankings in 2013 and 2014. The city is famous for the Edinburgh International Festival and the Fringe. The citys historical and cultural attractions have made it the United Kingdoms second most popular tourist destination after London, attracting over one million overseas visitors each year. Historic sites in Edinburgh include Edinburgh Castle, Holyrood Palace, the churches of St. Giles, Greyfriars and the Canongate, Edinburghs Old Town and New Town together are listed as a UNESCO World Heritage Site, which has been managed by Edinburgh World Heritage since 1999. It appears to derive from the place name Eidyn mentioned in the Old Welsh epic poem Y Gododdin, the poem names Din Eidyn as a hill fort in the territory of the Gododdin. The Celtic element din was dropped and replaced by the Old English burh, the first documentary evidence of the medieval burgh is a royal charter, c. 1124–1127, by King David I granting a toft in burgo meo de Edenesburg to the Priory of Dunfermline. In modern Gaelic, the city is called Dùn Èideann, the earliest known human habitation in the Edinburgh area was at Cramond, where evidence was found of a Mesolithic camp site dated to c.8500 BC. Traces of later Bronze Age and Iron Age settlements have found on Castle Rock, Arthurs Seat, Craiglockhart Hill. When the Romans arrived in Lothian at the end of the 1st century AD, at some point before the 7th century AD, the Gododdin, who were presumably descendants of the Votadini, built the hill fort of Din Eidyn or Etin. Although its location has not been identified, it likely they would have chosen a commanding position like the Castle Rock, Arthurs Seat. In 638, the Gododdin stronghold was besieged by forces loyal to King Oswald of Northumbria and it thenceforth remained under their jurisdiction. The royal burgh was founded by King David I in the early 12th century on land belonging to the Crown, in 1638, King Charles Is attempt to introduce Anglican church forms in Scotland encountered stiff Presbyterian opposition culminating in the conflicts of the Wars of the Three Kingdoms. In the 17th century, Edinburghs boundaries were defined by the citys defensive town walls
2.
Cambridge
–
Cambridge is a university city and the county town of Cambridgeshire, England, on the River Cam about 50 miles north of London. At the United Kingdom Census 2011, its population was 123,867, there is archaeological evidence of settlement in the area in the Bronze Age and in Roman Britain, under Viking rule, Cambridge became an important trading centre. The first town charters were granted in the 12th century, although city status was not conferred until 1951, the University of Cambridge, founded in 1209, is one of the top five universities in the world. The university includes the Cavendish Laboratory, Kings College Chapel, the citys skyline is dominated by the last two buildings, along with the spire of the Our Lady and the English Martyrs Church, the chimney of Addenbrookes Hospital and St Johns College Chapel tower. Anglia Ruskin University, evolved from the Cambridge School of Art, Cambridge is at the heart of the high-technology Silicon Fen with industries such as software and bioscience and many start-up companies spun out of the university. More than 40% of the workforce has a higher education qualification, the Cambridge Biomedical Campus, one of the largest biomedical research clusters in the world, is soon to be home to AstraZeneca, a hotel and the relocated Papworth Hospital. Parkers Piece hosted the first ever game of Association football, the Strawberry Fair music and arts festival and Midsummer Fairs are held on Midsummer Common, and the annual Cambridge Beer Festival takes place on Jesus Green. The city is adjacent to the M11 and A14 roads, settlements have existed around the Cambridge area since prehistoric times. The earliest clear evidence of occupation is the remains of a 3, the principal Roman site is a small fort Duroliponte on Castle Hill, just northwest of the city centre around the location of the earlier British village. The fort was bounded on two sides by the lines formed by the present Mount Pleasant, continuing across Huntingdon Road into Clare Street, the eastern side followed Magrath Avenue, with the southern side running near to Chesterton Lane and Kettles Yard before turning northwest at Honey Hill. It was constructed around AD70 and converted to use around 50 years later. Evidence of more widespread Roman settlement has been discovered including numerous farmsteads, evidence exists that the invading Anglo-Saxons had begun occupying the area by the end of the century. Their settlement—also on and around Castle Hill—became known as Grantebrycge, Anglo-Saxon grave goods have been found in the area. During this period, Cambridge benefited from good trade links across the hard-to-travel fenlands, by the 7th century, the town was less significant and described by Bede as a little ruined city containing the burial site of Etheldreda. Cambridge was on the border between the East and Middle Anglian kingdoms and the settlement slowly expanded on both sides of the river, the arrival of the Vikings was recorded in the Anglo-Saxon Chronicle in 875. Viking rule, the Danelaw, had been imposed by 878 Their vigorous trading habits caused the town to grow rapidly. During this period the centre of the town shifted from Castle Hill on the bank of the river to the area now known as the Quayside on the right bank. In 1068, two years after his conquest of England, William of Normandy built a castle on Castle Hill, like the rest of the newly conquered kingdom, Cambridge fell under the control of the King and his deputies
3.
University of Edinburgh
–
The University of Edinburgh, founded in 1582, is the sixth oldest university in the English-speaking world and one of Scotlands ancient universities. The university is deeply embedded in the fabric of the city of Edinburgh, the University of Edinburgh was ranked 17th and 21st in the world by the 2014–15 and 2015-16 QS rankings. It is now ranked 19th in the according to 2016-17 QS Rankings. It is ranked 16th in the world in arts and humanities by the 2015–16 Times Higher Education Ranking and it is ranked the 23rd most employable university in the world by the 2015 Global Employability University Ranking. It is ranked as the 6th best university in Europe by the U. S. News Best Global Universities Ranking and it is a member of both the Russell Group, and the League of European Research Universities, a consortium of 21 research universities in Europe. It has the third largest endowment of any university in the United Kingdom, after the universities of Cambridge and it continues to have links to the British Royal Family, having had the Duke of Edinburgh as its Chancellor from 1953 to 2010 and Princess Anne since 2011. Edinburgh receives approximately 50,000 applications every year, making it the fourth most popular university in the UK by volume of applicants, after St Andrews, it is the most difficult university to gain admission into in Scotland, and 9th overall in the UK. This was a move at the time, as most universities were established through Papal bulls. Established as the Tounis College, it opened its doors to students in October 1583, instruction began under the charge of another St Andrews graduate Robert Rollock. It was the fourth Scottish university in a period when the more populous. It was renamed King Jamess College in 1617, by the 18th century, the university was a leading centre of the Scottish Enlightenment. The universitys first custom-built building was the Old College, now Edinburgh Law School and its first forte in teaching was anatomy and the developing science of surgery, from which it expanded into many other subjects. From the basement of a nearby house ran the anatomy tunnel corridor and it went under what was then North College Street, and under the university buildings until it reached the universitys anatomy lecture theatre, delivering bodies for dissection. It was from this tunnel the body of William Burke was taken after he had been hanged, towards the end of the 19th century, Old College was becoming overcrowded and Robert Rowand Anderson was commissioned to design new Medical School premises in 1875. The medical school was more or less built to his design and was completed by the addition of the McEwan Hall in the 1880s. The building now known as New College was originally built as a Free Church college in the 1840s and has been the home of divinity at the university since the 1920s. The two oldest schools – law and divinity – are both well-esteemed, with law being based in Old College and divinity in New College on the Mound and they are also represented by the Edinburgh University Sports Union which was founded in 1866. The medical school is renowned throughout the world and it was widely considered the best medical school in the English-speaking world throughout the 18th century and first half of the 19th century
4.
University of Cambridge
–
The University of Cambridge is a collegiate public research university in Cambridge, England, often regarded as one of the most prestigious universities in the world. Founded in 1209 and given royal status by King Henry III in 1231, Cambridge is the second-oldest university in the English-speaking world. The university grew out of an association of scholars who left the University of Oxford after a dispute with the townspeople, the two ancient universities share many common features and are often referred to jointly as Oxbridge. Cambridge is formed from a variety of institutions which include 31 constituent colleges, Cambridge University Press, a department of the university, is the worlds oldest publishing house and the second-largest university press in the world. The university also operates eight cultural and scientific museums, including the Fitzwilliam Museum, Cambridges libraries hold a total of around 15 million books, eight million of which are in Cambridge University Library, a legal deposit library. In the year ended 31 July 2015, the university had an income of £1.64 billion. The central university and colleges have an endowment of around £5.89 billion. The university is linked with the development of the high-tech business cluster known as Silicon Fen. It is a member of associations and forms part of the golden triangle of leading English universities and Cambridge University Health Partners. As of 2017, Cambridge is ranked the fourth best university by three ranking tables and no other institution in the world ranks in the top 10 for as many subjects. Cambridge is consistently ranked as the top university in the United Kingdom, the university has educated many notable alumni, including eminent mathematicians, scientists, politicians, lawyers, philosophers, writers, actors, and foreign Heads of State. Ninety-five Nobel laureates, fifteen British prime ministers and ten Fields medalists have been affiliated with Cambridge as students, faculty, by the late 12th century, the Cambridge region already had a scholarly and ecclesiastical reputation, due to monks from the nearby bishopric church of Ely. The University of Oxford went into suspension in protest, and most scholars moved to such as Paris, Reading. After the University of Oxford reformed several years later, enough remained in Cambridge to form the nucleus of the new university. A bull in 1233 from Pope Gregory IX gave graduates from Cambridge the right to teach everywhere in Christendom, the colleges at the University of Cambridge were originally an incidental feature of the system. No college is as old as the university itself, the colleges were endowed fellowships of scholars. There were also institutions without endowments, called hostels, the hostels were gradually absorbed by the colleges over the centuries, but they have left some indicators of their time, such as the name of Garret Hostel Lane. Hugh Balsham, Bishop of Ely, founded Peterhouse, Cambridges first college, the most recently established college is Robinson, built in the late 1970s
5.
Maxwell's equations
–
Maxwells equations are a set of partial differential equations that, together with the Lorentz force law, form the foundation of classical electromagnetism, classical optics, and electric circuits. They underpin all electric, optical and radio such as power generation, electric motors, wireless communication, cameras, televisions. Maxwells equations describe how electric and magnetic fields are generated by charges, currents, one important consequence of the equations is the demonstration of how fluctuating electric and magnetic fields can propagate at the speed of light. This electromagnetic radiation manifests itself in ways from radio waves to light. The equations have two major variants, the microscopic Maxwell equations have universal applicability but are unwieldy for common calculations. They relate the electric and magnetic fields to total charge and total current, including the complicated charges, the macroscopic Maxwell equations define two new auxiliary fields that describe the large-scale behaviour of matter without having to consider atomic scale details. However, their use requires experimentally determining parameters for a description of the electromagnetic response of materials. The term Maxwells equations is used for equivalent alternative formulations. The space-time formulations, are used in high energy and gravitational physics because they make the compatibility of the equations with special and general relativity manifest. In many situations, though, deviations from Maxwells equations are immeasurably small, exceptions include nonclassical light, photon-photon scattering, quantum optics, and many other phenomena related to photons or virtual photons. In the electric and magnetic field there are four equations. The two inhomogeneous equations describe how the fields vary in space due to sources, Gausss law describes how electric fields emanate from electric charges. Gausss law for magnetism describes magnetic fields as closed field lines not due to magnetic monopoles, the two homogeneous equations describe how the fields circulate around their respective sources. A separate law of nature, the Lorentz force law, describes how the electric and magnetic field act on charged particles, a version of this law was included in the original equations by Maxwell but, by convention, is no longer. The precise formulation of Maxwells equations depends on the definition of the quantities involved. Conventions differ with the systems, because various definitions and dimensions are changed by absorbing dimensionful factors like the speed of light c. This makes constants come out differently, the vector calculus formulation below has become standard. For formulations using tensor calculus or differential forms, see alternative formulations, for relativistically invariant formulations, see relativistic formulations
6.
Maxwell relations
–
Maxwells relations are a set of equations in thermodynamics which are derivable from the symmetry of second derivatives and from the definitions of the thermodynamic potentials. These relations are named for the nineteenth-century physicist James Clerk Maxwell, the structure of Maxwell relations is a statement of equality among the second derivatives for continuous functions. It follows directly from the fact that the order of differentiation of a function of two variables is irrelevant. It is seen that for every thermodynamic potential there are n/2 possible Maxwell relations where n is the number of variables for that potential. The thermodynamic square can be used as a mnemonic to recall, the usefulness of these relations lies in their quantifying entropy changes, which are not directly measurable, in terms of measurable quantities like temperature, volume, and pressure. Maxwell relations are based on simple partial differentiation rules, in particular the differential of a function. This leads to the identity d P d V = d T d S. The physical meaning of identity can be seen by noting that the two sides are the equivalent ways of writing the work done in an infinitesimal Carnot cycle. An equivalent way of writing the identity is ∂ ∂ =1, the Maxwell relations now follow directly. For example, T = ∂ ∂ = ∂ ∂ = V, the critical step is the penultimate one. The other Maxwell relations follow in similar fashion, for example, S = ∂ ∂ = ∂ ∂ = − V. The above are not the only Maxwell relationships, for example, if we have a single-component gas, then the number of particles N is also a natural variable of the above four thermodynamic potentials. The Maxwell relationship for the enthalpy with respect to pressure and particle number would then be, in addition, there are other thermodynamic potentials besides the four that are commonly used, and each of these potentials will yield a set of Maxwell relations. Each equation can be re-expressed using the relationship z =1 / z which are also known as Maxwell relations. Table of thermodynamic equations Thermodynamic equations
7.
Maxwell's demon
–
In the thought experiment, a demon controls a small door between two chambers of gas. As individual gas molecules approach the door, the demon quickly opens and shuts the door so that fast molecules pass into the other chamber, while slow molecules remain in the first chamber. Because faster molecules are hotter, the demons behavior causes one chamber to warm up as the other cools, thus decreasing entropy, the thought experiment first appeared in a letter Maxwell wrote to Peter Guthrie Tait on 11 December 1867. It appeared again in a letter to John William Strutt in 1871, in his letters and books, Maxwell described the agent opening the door between the chambers as a finite being. William Thomson was the first to use the demon for Maxwells concept, in the journal Nature in 1874. The second law is expressed as the assertion that in an isolated system. Maxwell conceived a thought experiment as a way of furthering the understanding of the second law and his description of the experiment is as follows. He will thus, without expenditure of work, raise the temperature of B and lower that of A, in other words, Maxwell imagines one container divided into two parts, A and B. Both parts are filled with the gas at equal temperatures. Observing the molecules on both sides, an imaginary demon guards a trapdoor between the two parts, when a faster-than-average molecule from A flies towards the trapdoor, the demon opens it, and the molecule will fly from A to B. Likewise, when a molecule from B flies towards the trapdoor. The average speed of the molecules in B will have increased while in A they will have slowed down on average, since average molecular speed corresponds to temperature, the temperature decreases in A and increases in B, contrary to the second law of thermodynamics. A heat engine operating between the thermal reservoirs A and B could extract useful work from this temperature difference. The essence of the argument is to show, by calculation. One of the most famous responses to this question was suggested in 1929 by Leó Szilárd, Szilárd pointed out that a real-life Maxwells demon would need to have some means of measuring molecular speed, and that the act of acquiring information would require an expenditure of energy. Since the demon and the gas are interacting, we must consider the total entropy of the gas, the expenditure of energy by the demon will cause an increase in the entropy of the demon, which will be larger than the lowering of the entropy of the gas. In 1960, Rolf Landauer raised an exception to this argument and he realized that some measuring processes need not increase thermodynamic entropy as long as they were thermodynamically reversible. He suggested these reversible measurements could be used to sort the molecules, however, due to the connection between thermodynamic entropy and information entropy, this also meant that the recorded measurement must not be erased
8.
Color triangle
–
A colour triangle is an arrangement of colours within a triangle, based on the additive combination of three primary colors at its corners. An additive colour space defined by three colors has a chromaticity gamut that is a color triangle, when the amounts of the primaries are constrained to be nonnegative. After the development of the CIE system, color triangles were used as chromaticity diagrams, since the sum of the three chromaticity values has a fixed value, it suffices to depict only two of the three values, using Cartesian co-ordinates. In the modern x, y diagram, the triangle bounded by the imaginary primaries X, Y, and Z has corners. Maxwell was intrigued by James David Forbess use of color tops, initially, he compared the color he observed on the spinning top with a paper of different color, in order to find a match. Later, he mounted a pair of papers, snow white and ivory black, in an inner circle, thereby creating shades of gray. For pale chrome he found 0.33 P C +0.55 U +0.12 E G =0.37 S W +0.63 B K. Next, he rearranged the equation to express the test color in terms of the primaries. This would be the precursor to the color matching functions of the CIE1931 color space, whose chromaticity diagram is shown above
9.
Maxwell material
–
A Maxwell material is a viscoelastic material having the properties both of elasticity and viscosity. It is named for James Clerk Maxwell who proposed the model in 1867 and it is also known as a Maxwell fluid. The Maxwell model can be represented by a viscous damper. This model describes the damper as a Newtonian fluid and models the spring with Hookes law, if we connect these two elements in parallel, we get a generalized model of Kelvin–Voigt material. In the former case, the viscosity corresponds to that for a Newtonian fluid, in the latter case, it has a slightly different meaning relating stress and rate of strain. The model is applied to the case of small deformations. For the large deformations we should include some geometrical non-linearity, for the simplest way of generalizing the Maxwell model, refer to the upper-convected Maxwell model. If a Maxwell material is deformed and held to a strain of ε0. Since the viscous element would not return to its original length, the Maxwell Model does not exhibit creep since it models strain as linear function of time. If a small stress is applied for a long time. Thus, Maxwell material is a type of liquid, the relaxation time constant is τ ≡ η / E. Generalized Maxwell material Kelvin–Voigt material Oldroyd material Standard Linear Solid Material Upper-convected Maxwell model
10.
Generalized Maxwell model
–
The Generalized Maxwell model also known as the Maxwell–Wiechert model is the most general form of the linear model for viscoelasticity. In this model several Maxwell elements are assembled in parallel and it takes into account that the relaxation does not occur at a single time, but in a set of times. Due to the presence of molecular segments of different lengths, with shorter ones contributing less than longer ones, the Wiechert model shows this by having as many spring–dashpot Maxwell elements as are necessary to accurately represent the distribution. The figure on the shows the generalised Wiechert model
11.
Displacement current
–
In electromagnetism, displacement current is a quantity appearing in Maxwells equations that is defined in terms of the rate of change of electric displacement field. Displacement current has the units as electric current, and it is a source of the magnetic field just as actual current is. However it is not a current of moving charges, but a time-varying electric field. In physical materials, there is also a contribution from the motion of charges bound in atoms. The idea was conceived by James Clerk Maxwell in his 1861 paper On Physical Lines of Force, Maxwell added displacement current to the electric current term in Ampères Circuital Law. In his 1865 paper A Dynamical Theory of the Electromagnetic Field Maxwell used this version of Ampères Circuital Law to derive the electromagnetic wave equation. This derivation is now accepted as a historical landmark in physics by virtue of uniting electricity, magnetism. The displacement current term is now seen as an addition that completed Maxwells equations and is necessary to explain many phenomena. The electric displacement field is defined as, D = ε0 E + P, the first term on the right hand side is present in material media and in free space. It doesnt necessarily come from any actual movement of charge, but it does have a magnetic field. Some authors apply the name displacement current to the first term by itself, the second term on the right hand side, called polarization current density, comes from the change in polarization of the individual molecules of the dielectric material. Polarization results when, under the influence of an electric field. The positive and negative charges in molecules separate, causing an increase in the state of polarization P, a changing state of polarization corresponds to charge movement and so is equivalent to a current, hence the term polarization current. Maxwell made no special treatment of the vacuum, treating it as a material medium, for Maxwell, the effect of P was simply to change the relative permittivity εr in the relation D = εrε0 E. The modern justification of displacement current is explained below, in this equation the use of ε accounts for the polarization of the dielectric. The scalar value of displacement current may also be expressed in terms of electric flux, the forms in terms of ε are correct only for linear isotropic materials. More generally ε may be replaced by a tensor, may depend upon the field itself. For a linear isotropic dielectric, the polarization P is given by, note that, ε = ε r ε0 = ε0
12.
Maxwell coil
–
A Maxwell coil is a device for producing a large volume of almost constant magnetic field. It is named in honour of the Scottish physicist James Clerk Maxwell, a Maxwell coil is an improvement of a Helmholtz coil, in operation it provides an even more uniform magnetic field, but at the expense of more material and complexity. A constant-field Maxwell coil set consists of three coils oriented on the surface of a virtual sphere. According to Maxwells original 1873 design, each of the coils should be of radius 47 R. The number of ampere-turns of each of the coils should equal exactly 4964 of the middle coil. This arrangement removes variations in field, up to its 6th-order derivative with respect to position. A gradient-field Maxwell coil is essentially the same geometry of the 3-coil configuration above, if the current in one of the coils is reversed, a uniform-gradient magnetic field is produced near the centre of the two coils. Maxwell describes the use of the 2-coil configuration for the generation of a force on a small test coil. A Maxwell coil of this type is similar to a Helmholtz coil with the distance increased from coil radius R to 3 R
13.
Smith's Prize
–
The Smiths Prize was the name of each of two prizes awarded annually to two research students in mathematics and theoretical Physics at the University of Cambridge from 1769. Following the reorganization in 1998, it is now awarded under the name of Smith-Knight Prize, the Smith Prize fund was founded by bequest of Robert Smith upon his death in 1768, having by his will left £3500 South Sea Company stock to the University. Every year two or more junior Bachelor of Arts students who had made the greatest progress in mathematics, the prize was awarded every year from 1769 to 1998 except 1917. From 1769 to 1885, the prize was awarded for the best performance in a series of examinations, in 1854 George Stokes included an examination question on a particular theorem which William Thomson had written to him about, which is now known as Stokes theorem. T. W. Körner notes Only a small number of students took the Smiths prize examination in the nineteenth century, in 1885, the examination was renamed Part III, and the prize was awarded for the best submitted essay rather than examination performance. The majority of prize-winners have gone on to professional mathematicians or physicists. The Rayleigh Prize was a prize, which was awarded for the first time in 1911. The Smiths and Rayleigh prizes were available to Cambridge graduate students who had been undergraduates at Cambridge. Knight Prize was established in 1974 for Cambridge graduates who had been undergraduates at other universities, the prize commemorates J. T. Knight, who had been an undergraduate student at Glasgow and a graduate student at Cambridge. He was killed in a car accident in Ireland in April 1970. Originally, in 1769, the prizes were worth £25 each, in 1867, they fell to £23 and in 1915 were still reported to be worth that amount. By 1930, the value had risen to about £30, and by 1940, by 1998, a Smith’s Prize was worth around £250. In 2007, the value of the three funds was roughly £175,000. In 1998 the Smith Prize, Rayleigh Prize and J. T, Knight Prize were replaced by the Smith-Knight Prize and Rayleigh-Knight Prize, the standard for the former being higher than that required for the latter. For the period up to 1940 a complete list is given in Barrow-Green including titles of prize essays from 1889-1940, the following is a selection from this list. Richer, M. J. Vartiainen, T. A. Fisher, J. Rosenzweig, J. Wierzba, wunderer, J. H. P. Dawes, D. M. Rodgers, H-M. Roche and B. M. J. B. Walker 2004 Oliver Rinne 2005 Guillaume Pierre Bascoul and Giuseppe Di Graziano 2007 Anders Hansen and Vladimir Lazić
14.
Physics
–
Physics is the natural science that involves the study of matter and its motion and behavior through space and time, along with related concepts such as energy and force. One of the most fundamental disciplines, the main goal of physics is to understand how the universe behaves. Physics is one of the oldest academic disciplines, perhaps the oldest through its inclusion of astronomy, Physics intersects with many interdisciplinary areas of research, such as biophysics and quantum chemistry, and the boundaries of physics are not rigidly defined. New ideas in physics often explain the mechanisms of other sciences while opening new avenues of research in areas such as mathematics. Physics also makes significant contributions through advances in new technologies that arise from theoretical breakthroughs, the United Nations named 2005 the World Year of Physics. Astronomy is the oldest of the natural sciences, the stars and planets were often a target of worship, believed to represent their gods. While the explanations for these phenomena were often unscientific and lacking in evidence, according to Asger Aaboe, the origins of Western astronomy can be found in Mesopotamia, and all Western efforts in the exact sciences are descended from late Babylonian astronomy. The most notable innovations were in the field of optics and vision, which came from the works of many scientists like Ibn Sahl, Al-Kindi, Ibn al-Haytham, Al-Farisi and Avicenna. The most notable work was The Book of Optics, written by Ibn Al-Haitham, in which he was not only the first to disprove the ancient Greek idea about vision, but also came up with a new theory. In the book, he was also the first to study the phenomenon of the pinhole camera, many later European scholars and fellow polymaths, from Robert Grosseteste and Leonardo da Vinci to René Descartes, Johannes Kepler and Isaac Newton, were in his debt. Indeed, the influence of Ibn al-Haythams Optics ranks alongside that of Newtons work of the same title, the translation of The Book of Optics had a huge impact on Europe. From it, later European scholars were able to build the devices as what Ibn al-Haytham did. From this, such important things as eyeglasses, magnifying glasses, telescopes, Physics became a separate science when early modern Europeans used experimental and quantitative methods to discover what are now considered to be the laws of physics. Newton also developed calculus, the study of change, which provided new mathematical methods for solving physical problems. The discovery of new laws in thermodynamics, chemistry, and electromagnetics resulted from greater research efforts during the Industrial Revolution as energy needs increased, however, inaccuracies in classical mechanics for very small objects and very high velocities led to the development of modern physics in the 20th century. Modern physics began in the early 20th century with the work of Max Planck in quantum theory, both of these theories came about due to inaccuracies in classical mechanics in certain situations. Quantum mechanics would come to be pioneered by Werner Heisenberg, Erwin Schrödinger, from this early work, and work in related fields, the Standard Model of particle physics was derived. Areas of mathematics in general are important to this field, such as the study of probabilities, in many ways, physics stems from ancient Greek philosophy
15.
Mathematics
–
Mathematics is the study of topics such as quantity, structure, space, and change. There is a range of views among mathematicians and philosophers as to the exact scope, Mathematicians seek out patterns and use them to formulate new conjectures. Mathematicians resolve the truth or falsity of conjectures by mathematical proof, when mathematical structures are good models of real phenomena, then mathematical reasoning can provide insight or predictions about nature. Through the use of abstraction and logic, mathematics developed from counting, calculation, measurement, practical mathematics has been a human activity from as far back as written records exist. The research required to solve mathematical problems can take years or even centuries of sustained inquiry, rigorous arguments first appeared in Greek mathematics, most notably in Euclids Elements. Galileo Galilei said, The universe cannot be read until we have learned the language and it is written in mathematical language, and the letters are triangles, circles and other geometrical figures, without which means it is humanly impossible to comprehend a single word. Without these, one is wandering about in a dark labyrinth, carl Friedrich Gauss referred to mathematics as the Queen of the Sciences. Benjamin Peirce called mathematics the science that draws necessary conclusions, David Hilbert said of mathematics, We are not speaking here of arbitrariness in any sense. Mathematics is not like a game whose tasks are determined by arbitrarily stipulated rules, rather, it is a conceptual system possessing internal necessity that can only be so and by no means otherwise. Albert Einstein stated that as far as the laws of mathematics refer to reality, they are not certain, Mathematics is essential in many fields, including natural science, engineering, medicine, finance and the social sciences. Applied mathematics has led to entirely new mathematical disciplines, such as statistics, Mathematicians also engage in pure mathematics, or mathematics for its own sake, without having any application in mind. There is no clear line separating pure and applied mathematics, the history of mathematics can be seen as an ever-increasing series of abstractions. The earliest uses of mathematics were in trading, land measurement, painting and weaving patterns, in Babylonian mathematics elementary arithmetic first appears in the archaeological record. Numeracy pre-dated writing and numeral systems have many and diverse. Between 600 and 300 BC the Ancient Greeks began a study of mathematics in its own right with Greek mathematics. Mathematics has since been extended, and there has been a fruitful interaction between mathematics and science, to the benefit of both. Mathematical discoveries continue to be made today, the overwhelming majority of works in this ocean contain new mathematical theorems and their proofs. The word máthēma is derived from μανθάνω, while the modern Greek equivalent is μαθαίνω, in Greece, the word for mathematics came to have the narrower and more technical meaning mathematical study even in Classical times
16.
Marischal College
–
Marischal College is a large granite building on Broad Street in the centre of Aberdeen in north-east Scotland, and since 2011 has acted as the headquarters of Aberdeen City Council. However, the building was constructed for and is on lease from the University of Aberdeen. Today, it provides corporate office space and public access to services, adjacent to the Town House. Many Aberdonians consider Marischal College to be an icon of the Granite City, the construction of the modern college building began in 1835, following the demolition of previous buildings on the site, and was completed in its present form in the early 1900s. It is the second largest granite building in the world, the buildings of Marischal College continued to be used for academic purposes until the mid-20th century and less and less until the early 2000s. During this period they were rebuilt and expanded upon. After a number of proposals, the majority of the building was leased to Aberdeen City Council to be restored and refurbished as office accommodation. The extensive renovation was completed on schedule and significantly under budget, the university has retained the Mitchell Hall and a number of other significant parts of the building for its own use, in addition to the Marischal Museum. Marischal College and University of Aberdeen was the name of the former university which occupied the present Marischal College site. The College was founded in 1593 by George Keith, 5th Earl Marischal of Scotland, the original charter of the university was lost by the early 18th century, but two near-contemporary copies exist – one of which was accepted by the courts in 1756 as being authentic. In this charter, Marischal College is described variously as a gymnasium, collegium, academia, as such, both Edinburgh and Marischal came to be known as the Town Colleges of their respective cities. The university was founded with the aim of training clergy for the post-Reformation Kirk. It is believed that Keith desired a protestant institution alongside the pre-Reformation Kings College and it is possible that the founding of another college in nearby Fraserburgh in 1592 was the true cause, its founder Sir Alexander Fraser was a business rival of Marischal. The College was constructed on the site of a medieval Franciscan Friary, the colleges Greek motto translates as virtue is self-sufficient. The Mitchell Hall, where University of Aberdeen graduations previously took place, was built in the early 20th century and it is named for Dr Charles Mitchell, an alumnus of the university and a Tyneside shipbuilder. A large stained-glass window dominates the hall, executed by TR Spence of London, the building was commended by poet John Betjeman following a visit to Aberdeen in 1947, No-one can dismiss Marischal College, Aberdeen, when looking at the work of the present century. Wedged behind a huge town hall in an expensive and attractive mid-Victorian baronial style, I turned down a lane towards them, the front broadened out. Bigger than any cathedral, tower on tower, forests of pinnacles and this was the famous Marischal College
17.
King's College London
–
Kings College London is a public research university located in London, United Kingdom, and a founding constituent college of the federal University of London. Kings was established in 1829 by King George IV and the Duke of Wellington, in 1836, Kings became one of the two founding colleges of the University of London. It is a member of organisations such as the Association of Commonwealth Universities, the European University Association. Kings has five campuses, its main campus on the Strand in central London. In 2015/16, Kings had an income of £738.4 million, of which £193.2 million was from research grants and contracts and as of 2014/15. It has the fifth largest endowment of any university in the United Kingdom, and its academic activities are organised into nine faculties which are subdivided into numerous departments, centres and research divisions. Kings is home to six Medical Research Council centres and is a member of the Kings Health Partners academic health sciences centre, Francis Crick Institute. Kings College London, so named to indicate the patronage of King George IV, was founded in 1829 in response to the controversy surrounding the founding of London University in 1826. The need for such an institution was a result of the religious and social nature of the universities of Oxford and Cambridge, which then educated solely the sons of wealthy Anglicans. The secular nature of London University was disapproved by The Establishment, indeed, thus, the creation of a rival institution represented a Tory response to reassert the educational values of The Establishment. Winchilsea and about 150 other contributors withdrew their support of Kings College London in response to Wellingtons support of Catholic emancipation. In a letter to Wellington he accused the Duke to have in mind insidious designs for the infringement of our liberty, the letter provoked a furious exchange of correspondence and Wellington accused Winchilsea of imputing him with disgraceful and criminal motives in setting up Kings College London. The result was a duel in Battersea Fields on 21 March 1829, Winchilsea did not fire, a plan he and his second almost certainly decided upon before the duel, Wellington took aim and fired wide to the right. Accounts differ as to whether Wellington missed on purpose, Wellington, noted for his poor aim, claimed he did, other reports more sympathetic to Winchilsea claimed he had aimed to kill. Honour was saved and Winchilsea wrote Wellington an apology, duel Day is still celebrated on the first Thursday after 21 March every year, marked by various events throughout Kings, including reenactments. Kings opened in October 1831 with the cleric William Otter appointed as first principal, despite the attempts to make Kings Anglican-only, the initial prospectus permitted, nonconformists of all sorts to enter the college freely. William Howley, the governors and the professors, except the linguists, had to be members of the Church of England but the students did not, though attendance at chapel was compulsory. Kings was divided into a department and a junior department, also known as Kings College School
18.
William Hopkins
–
William Hopkins FRS was an English mathematician and geologist. He is famous as a tutor of aspiring undergraduate Cambridge mathematicians. He also made important contributions in asserting a solid, rather than fluid, interior for the Earth, however, though his conclusions proved to be correct, his mathematical and physical reasoning were subsequently seen as unsound. Hopkins was born at Kingston-on-Soar, in Nottinghamshire, the son of William Hopkins. In his youth he learned practical agriculture in Norfolk before his father rented him a farm at Bury St Edmunds, Suffolk. A. in 1827 as seventh wrangler. Before graduation, Hopkins had married Caroline Frances Boys and was, therefore and he instead maintained himself as a private tutor, coaching the young mathematicians who sought the prestigious distinction of Senior Wrangler. He was enormously successful in the role, earning the sobriquet senior wrangler maker, by 1849, he had coached almost 200 wranglers, of whom 17 were senior wranglers including Arthur Cayley and G. G. Stokes. Among his more famous pupils were Lord Kelvin, James Clerk Maxwell, I never enjoyed anything so much before. He also coached Edward Routh who went on to be Senior Wrangler, in 1833, Hopkins published Elements of Trigonometry and became distinguished for his mathematical knowledge. There was a story that the theory of George Green was almost forgotten. In 1845, Lord Kelvin got some copies of Greens 1828 short book from William Hopkins, subsequently, Lord Kelvin helped to make Greens 1828 work famous according to the book George Green written by D. M. About 1833, through meeting Adam Sedgwick at Barmouth and joining him in several excursions, Hopkins became intensely interested in geology, in this way he discussed the elevation and denudation of the Lake District, the Wealden area, and the Bas Boulonnais. Hopkins conceived of a solid but dynamic Earth threaded with cavities whereby hot vapours or fluids could create locally elevatory pressures. Such a model was at odds with the ideas of Charles Lyell whose theory was of a state with a largely liquid terrestrial interior. He also interpreted earthquakes and volcanoes through the model in an 1847 British Association report. As part of his investigations, Hopkins sought to quantify the effects of enormous pressures on the melting point and he further asserted that the cooling of the Earth had had no real impact on climate. He read a paper to the Geological Society On the Causes which may have produced changes in the Earths superficial Temperature, ultimately, it was Thomson who tactfully pointed out that, though Hopkinss conclusions about the Earths structure were correct, his mathematical and physical reasoning was unsound. Hopkins enjoyed music, poetry and landscape painting and he spent the end of his life in a lunatic asylum in Stoke Newington
19.
George Chrystal
–
George Chrystal FRSE was a Scottish mathematician. He is primarily remembered for his books on algebra and for his studies of seiches which earned him a Gold Medal from the Royal Society of London. He was born in Old Meldrum on 8 March 1851, the son of William Chrystal a wealthy farmer and grain merchant and his wife, Margaret Burr. He was appointed to the Regius Chair of Mathematics at University of St. Andrews in 1877, in 1911, he was awarded the Royal Medal of the Royal Society for his researches into the surface oscillations of Scottish lakes. He was a contributor to the drafting of the Universities Act 1889 and he was elected a Fellow of the Royal Society of Edinburgh in 1880, his proposers including James Clerk Maxwell. He was awarded the Societys Keith Medal for 1879-81 and their Gunning Victoria Jubilee Prize for the period 1904-8 and he served as Vice President of the Society 1895-1901 and General Secretary 1901-1911. He was awarded two honorary doctorates, Aberdeen University in 1887 and Glasgow University in 1911 and he is credited with instigating the move of the Society from the Mound to George Street. In later life he is listed as living at 5 Belgrave Crescent in western Edinburgh, the mathematician Alexander G. Burgess trained under him. He grew very ill in 1909 and this early in 1911. A work-free summer did not improve him and he died on 3 November 1911 at 5 Belgrave Crescent in Edinburgh but was taken north for burial, and is buried in Foveran Churchyard in Aberdeenshire. He married Margaret Anne Balfour in 1879 and she died before him and is buried in the northern Victorian extension to Dean Cemetery with their son Walter MacDonald Chrystal who died in infancy. They had four sons and two daughters, algebra, An Elementary Text-Book for the Higher Classes of Secondary Schools and for Colleges. Three articles within the 1911 edition of Encyclopædia Britannica, Pascal, Blaise, Perpetual Motion, works written by or about George Chrystal at Wikisource OConnor, John J. Robertson, Edmund F. George Chrystal, MacTutor History of Mathematics archive, University of St Andrews. Algebra, An Elementary Text-Book for the Higher Classes of Secondary Schools and for Colleges
20.
Horace Lamb
–
Sir Horace Lamb FRS was an English applied mathematician and author of several influential texts on classical physics, among them Hydrodynamics and Dynamical Theory of Sound. Both of these books are still in print, Lamb was born at Stockport, Cheshire, the son of John Lamb and his wife Elizabeth, née Rangeley. His father John Lamb, was a foreman in a cotton mill, John Lamb died when his son was quite young. His widow married again and shortly afterwards Horace went to live with his mothers sister and he studied at Stockport Grammar School where he found a wise and kindly head master, the Rev. Charles Hamilton. To his insight and influence Lamb felt that he owed his start in life, Mr. Hamilton was an excellent teacher, both of classics and elementary mathematics, and from him we are told his pupil acquired a passing enthusiasm for Greek and Latin poets. In 1867, when only seventeen, he gained a scholarship at Queens College, Cambridge. He was very young and was advised to decline this and work for a year at the Owens College, Professor Barker, Professor of Mathematics, had been Senior Wrangler in 1862, and was a former Fellow of Trinity. His professors included James Clerk Maxwell and George Gabriel Stokes, for recreation he took long walks in the country about Cambridge, with an occasional visit to Switzerland. He read much in French, German, and Italian, Lamb had become engaged to Miss Elizabeth Foot, of Dublin, the sister-in-law of his former head master, Mr Hamilton. His marriage took place in 1875 and after the voyage round the Cape, Professor. At first they stayed with Mr. and Mrs Poole, but in June,1876, in 1875 Lamb was appointed the first Elder Professor of Mathematics at the newly founded University of Adelaide. For the next 10 years the number of students doing the arts course at Adelaide was fewer than 12, though Lamb also did some popular lecturing. In 1878 appeared his able and original A Treatise on the Mathematical Theory of the Motions of Fluids. Lamb was appointed to the Chair of Mathematics at Owens College, Manchester, in 1885 and which became the Beyer Chair in 1888, a position Lamb held until retirement in 1920. In 1932 Lamb, in an address to the British Association for the Advancement of Science and he reportedly said, I am an old man now, and when I die and go to heaven there are two matters on which I hope for enlightenment. One is quantum electrodynamics, and the other is the turbulent motion of fluids, and about the former I am rather optimistic. Lamb is also known for description of waves in thin solid layers. Now these waves are called Lamb waves, in 1875, Lamb married Elizabeth Foot of Dublin
21.
John Henry Poynting
–
John Henry Poynting was an English physicist. He was a professor of physics at Mason Science College, from 1880 to 1900, and then the successor institution, Poynting was the youngest son of Thomas Elford Poynting, a Unitarian minister. He was born at the parsonage of the Monton Unitarian Chapel in Eccles, from 1867 to 1872 he attended Owens College, now the University of Manchester, where his physics teachers included Osborne Reynolds and Balfour Stewart. From 1872 to 1876 he was a student at Cambridge University, in the late 1870s he worked in the Cavendish Laboratory at Cambridge under James Clerk Maxwell. This work was first published in 1884 and he performed a measurement of Newtons gravitational constant by innovative means during 1893. In 1903 he was the first to realise that the Suns radiation can draw in small particles towards it and he discovered the torsion-extension coupling in finite strain elasticity. This is now known as the Poynting effect in torsion and he was awarded an honorary MSc in Pure Science in 1901 by Birmingham University. Poynting lived at 11 St Augustines Road, Edgbaston with his family and he previously lived at 66 Beaufort Road, Edgbaston and died of a diabetic coma, aged 61, at 10 Ampton Road, Edgbaston in 1914. Craters on Mars and the Moon are named in his honour, as is the main Physics building at the University of Birmingham and the society there
22.
Isaac Newton
–
His book Philosophiæ Naturalis Principia Mathematica, first published in 1687, laid the foundations of classical mechanics. Newton also made contributions to optics, and he shares credit with Gottfried Wilhelm Leibniz for developing the infinitesimal calculus. Newtons Principia formulated the laws of motion and universal gravitation that dominated scientists view of the universe for the next three centuries. Newtons work on light was collected in his influential book Opticks. He also formulated a law of cooling, made the first theoretical calculation of the speed of sound. Newton was a fellow of Trinity College and the second Lucasian Professor of Mathematics at the University of Cambridge, politically and personally tied to the Whig party, Newton served two brief terms as Member of Parliament for the University of Cambridge, in 1689–90 and 1701–02. He was knighted by Queen Anne in 1705 and he spent the last three decades of his life in London, serving as Warden and Master of the Royal Mint and his father, also named Isaac Newton, had died three months before. Born prematurely, he was a child, his mother Hannah Ayscough reportedly said that he could have fit inside a quart mug. When Newton was three, his mother remarried and went to live with her new husband, the Reverend Barnabas Smith, leaving her son in the care of his maternal grandmother, Newtons mother had three children from her second marriage. From the age of twelve until he was seventeen, Newton was educated at The Kings School, Grantham which taught Latin and Greek. He was removed from school, and by October 1659, he was to be found at Woolsthorpe-by-Colsterworth, Henry Stokes, master at the Kings School, persuaded his mother to send him back to school so that he might complete his education. Motivated partly by a desire for revenge against a bully, he became the top-ranked student. In June 1661, he was admitted to Trinity College, Cambridge and he started as a subsizar—paying his way by performing valets duties—until he was awarded a scholarship in 1664, which guaranteed him four more years until he would get his M. A. He set down in his notebook a series of Quaestiones about mechanical philosophy as he found it, in 1665, he discovered the generalised binomial theorem and began to develop a mathematical theory that later became calculus. Soon after Newton had obtained his B. A. degree in August 1665, in April 1667, he returned to Cambridge and in October was elected as a fellow of Trinity. Fellows were required to become ordained priests, although this was not enforced in the restoration years, however, by 1675 the issue could not be avoided and by then his unconventional views stood in the way. Nevertheless, Newton managed to avoid it by means of a special permission from Charles II. A and he was elected a Fellow of the Royal Society in 1672. Newtons work has been said to distinctly advance every branch of mathematics then studied and his work on the subject usually referred to as fluxions or calculus, seen in a manuscript of October 1666, is now published among Newtons mathematical papers
23.
Michael Faraday
–
Michael Faraday FRS was an English scientist who contributed to the study of electromagnetism and electrochemistry. His main discoveries include the principles underlying electromagnetic induction, diamagnetism, although Faraday received little formal education, he was one of the most influential scientists in history. It was by his research on the field around a conductor carrying a direct current that Faraday established the basis for the concept of the electromagnetic field in physics. Faraday also established that magnetism could affect rays of light and that there was a relationship between the two phenomena. He similarly discovered the principles of induction and diamagnetism. His inventions of electromagnetic rotary devices formed the foundation of electric motor technology, Faraday ultimately became the first and foremost Fullerian Professor of Chemistry at the Royal Institution of Great Britain, a lifetime position. James Clerk Maxwell took the work of Faraday and others and summarized it in a set of equations which is accepted as the basis of all theories of electromagnetic phenomena. The SI unit of capacitance is named in his honour, the farad, albert Einstein kept a picture of Faraday on his study wall, alongside pictures of Isaac Newton and James Clerk Maxwell. Faraday was born in Newington Butts, which is now part of the London Borough of Southwark but was then a part of Surrey. His family was not well off and his father, James, was a member of the Glassite sect of Christianity. James Faraday moved his wife and two children to London during the winter of 1790 from Outhgill in Westmorland, where he had been an apprentice to the village blacksmith, Michael was born in the autumn of that year. The young Michael Faraday, who was the third of four children, at the age of 14 he became an apprentice to George Riebau, a local bookbinder and bookseller in Blandford Street. During his seven-year apprenticeship Faraday read many books, including Isaac Wattss The Improvement of the Mind, at this time he also developed an interest in science, especially in electricity. Faraday was particularly inspired by the book Conversations on Chemistry by Jane Marcet, many of the tickets for these lectures were given to Faraday by William Dance, who was one of the founders of the Royal Philharmonic Society. Faraday subsequently sent Davy a 300-page book based on notes that he had taken during these lectures, davys reply was immediate, kind, and favourable. In 1813, when Davy damaged his eyesight in an accident with nitrogen trichloride, very soon Davy entrusted Faraday with the preparation of nitrogen trichloride samples, and they both were injured in an explosion of this very sensitive substance. In the class-based English society of the time, Faraday was not considered a gentleman, Faraday was forced to fill the role of valet as well as assistant throughout the trip. Davys wife, Jane Apreece, refused to treat Faraday as an equal, the trip did, however, give him access to the scientific elite of Europe and exposed him to a host of stimulating ideas
24.
Albert Einstein
–
Albert Einstein was a German-born theoretical physicist. He developed the theory of relativity, one of the two pillars of modern physics, Einsteins work is also known for its influence on the philosophy of science. Einstein is best known in popular culture for his mass–energy equivalence formula E = mc2, near the beginning of his career, Einstein thought that Newtonian mechanics was no longer enough to reconcile the laws of classical mechanics with the laws of the electromagnetic field. This led him to develop his theory of relativity during his time at the Swiss Patent Office in Bern. Briefly before, he aquired the Swiss citizenship in 1901, which he kept for his whole life and he continued to deal with problems of statistical mechanics and quantum theory, which led to his explanations of particle theory and the motion of molecules. He also investigated the properties of light which laid the foundation of the photon theory of light. In 1917, Einstein applied the theory of relativity to model the large-scale structure of the universe. He was visiting the United States when Adolf Hitler came to power in 1933 and, being Jewish, did not go back to Germany and he settled in the United States, becoming an American citizen in 1940. This eventually led to what would become the Manhattan Project, Einstein supported defending the Allied forces, but generally denounced the idea of using the newly discovered nuclear fission as a weapon. Later, with the British philosopher Bertrand Russell, Einstein signed the Russell–Einstein Manifesto, Einstein was affiliated with the Institute for Advanced Study in Princeton, New Jersey, until his death in 1955. Einstein published more than 300 scientific papers along with over 150 non-scientific works, on 5 December 2014, universities and archives announced the release of Einsteins papers, comprising more than 30,000 unique documents. Einsteins intellectual achievements and originality have made the word Einstein synonymous with genius, Albert Einstein was born in Ulm, in the Kingdom of Württemberg in the German Empire, on 14 March 1879. His parents were Hermann Einstein, a salesman and engineer, the Einsteins were non-observant Ashkenazi Jews, and Albert attended a Catholic elementary school in Munich from the age of 5 for three years. At the age of 8, he was transferred to the Luitpold Gymnasium, the loss forced the sale of the Munich factory. In search of business, the Einstein family moved to Italy, first to Milan, when the family moved to Pavia, Einstein stayed in Munich to finish his studies at the Luitpold Gymnasium. His father intended for him to electrical engineering, but Einstein clashed with authorities and resented the schools regimen. He later wrote that the spirit of learning and creative thought was lost in strict rote learning, at the end of December 1894, he travelled to Italy to join his family in Pavia, convincing the school to let him go by using a doctors note. During his time in Italy he wrote an essay with the title On the Investigation of the State of the Ether in a Magnetic Field
25.
Fellow of the Royal Society
–
As of 2016, there are around 1600 living Fellows, Foreign and Honorary Members. Fellowship of the Royal Society has been described by The Guardian newspaper as “the equivalent of a lifetime achievement Oscar” with several institutions celebrating their announcement each year. Up to 60 new Fellows, honorary and foreign members are elected annually usually in May, each candidate is considered on their merits and can be proposed from any sector of the scientific community. Fellows are elected for life on the basis of excellence in science and are entitled to use the post-nominal letters FRS, see Category, Fellows of the Royal Society and Category, Female Fellows of the Royal Society. Every year, Fellows elect up to ten new Foreign Members, like Fellows, Foreign Members are elected for life through peer review on the basis of excellence in science. As of 2016 there are around 165 Foreign Members, who are entitled to use the post-nominal ForMemRS, see Category, Foreign Members of the Royal Society. Honorary Fellows include Bill Bryson, Melvyn Bragg, Robin Saxby, David Sainsbury, Baron Sainsbury of Turville, Honorary Fellows are entitled to use the post nominal letters HonFRS. Others including John Maddox, Patrick Moore and Lisa Jardine were elected as honorary fellows, statute 12 is a legacy mechanism for electing members before official honorary membership existed in 1997. Fellows elected under statute 12 include David Attenborough and John Palmer, prime Ministers of the United Kingdom such as Margaret Thatcher, Neville Chamberlain, H. H. Asquith were elected under statute 12, see Category, Fellows of the Royal Society. The Council of the Royal Society can recommend members of the British Royal Family for election as Royal Fellows of the Royal Society. As of 2016 there are five royal fellows, Charles, Prince of Wales, Anne, Princess Royal, Prince Edward, Duke of Kent, Prince William, Duke of Cambridge and Prince Andrew, Duke of York. Her Majesty the Queen, Elizabeth II is not a Royal Fellow, Prince Philip, Duke of Edinburgh was elected under statute 12, not as a Royal Fellow. The election of new fellows is announced annually in May, after their nomination, each candidate for Fellowship or Foreign Membership is nominated by two Fellows of the Royal Society, who sign a certificate of proposal. Previously, nominations required at least five fellows to support each nomination by the proposer, the certificate of election includes a statement of the principal grounds on which the proposal is being made. There is no limit on the number of nominations each year. In 2015, there were 654 candidates for election as Fellows and 106 candidates for Foreign Membership. The final list of up to 52 Fellowship candidates and up to 10 Foreign Membership candidates is confirmed by the Council in April, a candidate is elected if he or she secures two-thirds of votes of those Fellows present and voting. A further maximum of six can be ‘Honorary’, ‘General’ or ‘Royal’ Fellows, nominations for Fellowship are peer reviewed by sectional committees, each with fifteen members and a chair
26.
Fellow of the Royal Society of Edinburgh
–
Fellowship of the Royal Society of Edinburgh is an award granted to individuals that the Royal Society of Edinburgh judges to be eminently distinguished in their subject. Around 50 new fellows are elected each year in March, as of 2016 there are around 1650 Fellows, including 71 Honorary Fellows and 76 Corresponding Fellows. Fellows are entitled to use the post-nominal letters FRSE, examples of fellows include Peter Higgs and Jocelyn Bell Burnell. Previous fellows have included Melvin Calvin and Benjamin Franklin, see the Category, Fellows of the Royal Society of Edinburgh for more examples
27.
Scientist
–
A scientist is a person engaging in a systematic activity to acquire knowledge that describes and predicts the natural world. In a more restricted sense, a scientist may refer to an individual who uses the scientific method, the person may be an expert in one or more areas of science. The term scientist was coined by the theologian, philosopher and historian of science William Whewell and this article focuses on the more restricted use of the word. Scientists perform research toward a comprehensive understanding of nature, including physical, mathematical and social realms. Philosophers aim to provide an understanding of fundamental aspects of reality and experience, often pursuing inquiries with conceptual, rather than empirical. When science is done with a goal toward practical utility, it is called applied science, an applied scientist may not be designing something in particular, but rather is conducting research with the aim of developing new technologies and practical methods. When science seeks to answer questions about aspects of reality it is sometimes called natural philosophy. Science and technology have continually modified human existence through the engineering process, as a profession the scientist of today is widely recognized. Jurisprudence and mathematics are often grouped with the sciences, some of the greatest physicists have also been creative mathematicians and lawyers. There is a continuum from the most theoretical to the most empirical scientists with no distinct boundaries, in terms of personality, interests, training and professional activity, there is little difference between applied mathematicians and theoretical physicists. Scientists can be motivated in several ways, many have a desire to understand why the world is as we see it and how it came to be. They exhibit a strong curiosity about reality, other motivations are recognition by their peers and prestige, or the desire to apply scientific knowledge for the benefit of peoples health, the nations, the world, nature or industries. Scientists tend to be motivated by direct financial reward for their work than other careers. As a result, scientific researchers often accept lower average salaries when compared with other professions which require a similar amount of training. The number of scientists is vastly different from country to country, for instance, there are only 4 full-time scientists per 10,000 workers in India while this number is 79 for the United Kingdom and the United States. According to the US National Science Foundation 4.7 million people with science degrees worked in the United States in 2015, across all disciplines, the figure included twice as many men as women. Of that total, 17% worked in academia, that is, at universities and undergraduate institutions, 5% of scientists worked for the federal government and about 3. 5% were self-employed. Of the latter two groups, two-thirds were men, 59% of US scientists were employed in industry or business, and another 6% worked in non-profit positions
28.
Mathematical physics
–
Mathematical physics refers to development of mathematical methods for application to problems in physics. It is a branch of applied mathematics, but deals with physical problems, there are several distinct branches of mathematical physics, and these roughly correspond to particular historical periods. The rigorous, abstract and advanced re-formulation of Newtonian mechanics adopting the Lagrangian mechanics, both formulations are embodied in analytical mechanics. These approaches and ideas can be and, in fact, have extended to other areas of physics as statistical mechanics, continuum mechanics, classical field theory. Moreover, they have provided several examples and basic ideas in differential geometry, the theory of partial differential equations are perhaps most closely associated with mathematical physics. These were developed intensively from the half of the eighteenth century until the 1930s. Physical applications of these developments include hydrodynamics, celestial mechanics, continuum mechanics, elasticity theory, acoustics, thermodynamics, electricity, magnetism, and aerodynamics. The theory of atomic spectra developed almost concurrently with the fields of linear algebra. Nonrelativistic quantum mechanics includes Schrödinger operators, and it has connections to atomic, Quantum information theory is another subspecialty. The special and general theories of relativity require a different type of mathematics. This was group theory, which played an important role in quantum field theory and differential geometry. This was, however, gradually supplemented by topology and functional analysis in the description of cosmological as well as quantum field theory phenomena. In this area both homological algebra and category theory are important nowadays, statistical mechanics forms a separate field, which includes the theory of phase transitions. It relies upon the Hamiltonian mechanics and it is related with the more mathematical ergodic theory. There are increasing interactions between combinatorics and physics, in statistical physics. The usage of the mathematical physics is sometimes idiosyncratic. Certain parts of mathematics that arose from the development of physics are not, in fact, considered parts of mathematical physics. The term mathematical physics is sometimes used to research aimed at studying and solving problems inspired by physics or thought experiments within a mathematically rigorous framework
29.
Electromagnetic radiation
–
In physics, electromagnetic radiation refers to the waves of the electromagnetic field, propagating through space carrying electromagnetic radiant energy. It includes radio waves, microwaves, infrared, light, ultraviolet, X-, classically, electromagnetic radiation consists of electromagnetic waves, which are synchronized oscillations of electric and magnetic fields that propagate at the speed of light through a vacuum. The oscillations of the two fields are perpendicular to other and perpendicular to the direction of energy and wave propagation. The wavefront of electromagnetic waves emitted from a point source is a sphere, the position of an electromagnetic wave within the electromagnetic spectrum can be characterized by either its frequency of oscillation or its wavelength. Electromagnetic waves are produced whenever charged particles are accelerated, and these waves can interact with other charged particles. EM waves carry energy, momentum and angular momentum away from their source particle, quanta of EM waves are called photons, whose rest mass is zero, but whose energy, or equivalent total mass, is not zero so they are still affected by gravity. Thus, EMR is sometimes referred to as the far field, in this language, the near field refers to EM fields near the charges and current that directly produced them, specifically, electromagnetic induction and electrostatic induction phenomena. In the quantum theory of electromagnetism, EMR consists of photons, quantum effects provide additional sources of EMR, such as the transition of electrons to lower energy levels in an atom and black-body radiation. The energy of a photon is quantized and is greater for photons of higher frequency. This relationship is given by Plancks equation E = hν, where E is the energy per photon, ν is the frequency of the photon, a single gamma ray photon, for example, might carry ~100,000 times the energy of a single photon of visible light. The effects of EMR upon chemical compounds and biological organisms depend both upon the power and its frequency. EMR of visible or lower frequencies is called non-ionizing radiation, because its photons do not individually have enough energy to ionize atoms or molecules, the effects of these radiations on chemical systems and living tissue are caused primarily by heating effects from the combined energy transfer of many photons. In contrast, high ultraviolet, X-rays and gamma rays are called ionizing radiation since individual photons of high frequency have enough energy to ionize molecules or break chemical bonds. These radiations have the ability to cause chemical reactions and damage living cells beyond that resulting from simple heating, Maxwell derived a wave form of the electric and magnetic equations, thus uncovering the wave-like nature of electric and magnetic fields and their symmetry. Because the speed of EM waves predicted by the wave equation coincided with the speed of light. Maxwell’s equations were confirmed by Heinrich Hertz through experiments with radio waves, according to Maxwells equations, a spatially varying electric field is always associated with a magnetic field that changes over time. Likewise, a varying magnetic field is associated with specific changes over time in the electric field. In an electromagnetic wave, the changes in the field are always accompanied by a wave in the magnetic field in one direction
30.
Magnetism
–
Magnetism is a class of physical phenomena that are mediated by magnetic fields. Electric currents and the moments of elementary particles give rise to a magnetic field. The most familiar effects occur in materials, which are strongly attracted by magnetic fields and can be magnetized to become permanent magnets. Only a few substances are ferromagnetic, the most common ones are iron, nickel and cobalt, the prefix ferro- refers to iron, because permanent magnetism was first observed in lodestone, a form of natural iron ore called magnetite, Fe3O4. The magnetic state of a material depends on temperature and other such as pressure. A material may exhibit more than one form of magnetism as these variables change, magnetism was first discovered in the ancient world, when people noticed that lodestones, naturally magnetized pieces of the mineral magnetite, could attract iron. The word magnet comes from the Greek term for lodestone, magnítis líthos, in ancient Greece, Aristotle attributed the first of what could be called a scientific discussion of magnetism to the philosopher Thales of Miletus, who lived from about 625 BC to about 545 BC. Around the same time, in ancient India, the Indian surgeon Sushruta was the first to use of the magnet for surgical purposes. In ancient China, the earliest literary reference to magnetism lies in a 4th-century BC book named after its author, the 2nd-century BC annals, Lüshi Chunqiu, also notes, The lodestone makes iron approach, or it attracts it. The earliest mention of the attraction of a needle is in a 1st-century work Lunheng, by the 12th century the Chinese were known to use the lodestone compass for navigation. They sculpted a directional spoon from lodestone in such a way that the handle of the spoon always pointed south, alexander Neckam, by 1187, was the first in Europe to describe the compass and its use for navigation. In 1269, Peter Peregrinus de Maricourt wrote the Epistola de magnete, in 1282, the properties of magnets and the dry compass were discussed by Al-Ashraf, a Yemeni physicist, astronomer, and geographer. In 1600, William Gilbert published his De Magnete, Magneticisque Corporibus, in this work he describes many of his experiments with his model earth called the terrella. From his experiments, he concluded that the Earth was itself magnetic and this landmark experiment is known as Ørsteds Experiment. James Clerk Maxwell synthesized and expanded these insights into Maxwells equations, unifying electricity, magnetism, in 1905, Einstein used these laws in motivating his theory of special relativity, requiring that the laws held true in all inertial reference frames. Magnetism, at its root, arises from two sources, Electric current, Spin magnetic moments of elementary particles. The magnetic moments of the nuclei of atoms are thousands of times smaller than the electrons magnetic moments. Nuclear magnetic moments are very important in other contexts, particularly in nuclear magnetic resonance
31.
A Dynamical Theory of the Electromagnetic Field
–
A Dynamical Theory of the Electromagnetic Field is the third of James Clerk Maxwells papers regarding electromagnetism, published in 1865. In the paper, Maxwell derives an electromagnetic wave equation with a velocity for light in close agreement with measurements made by experiment, and deduces that light is an electromagnetic wave. Following standard procedure for the time, the paper was first read to the Royal Society on 8 December 1864 and it then underwent peer review, being sent to William Thompson on 24 December 1864. It was then sent to George Gabriel Stokes, the Societys Physical Sciences Secretary and it was approved for publication in the Philosophical Transactions of the Royal Society on 15 June 1865, by the Committee of Papers and sent to the printer the following day. During this period, Philosophical Transactions was only published as a volume once a year. However, the printer would have prepared and delivered to Maxwell offprints, for the author to distribute as he wished, Heavisides versions of Maxwells equations are distinct by virtue of the fact that they are written in modern vector notation. They actually only one of the original eight—equation G. Another of Heavisides four equations is an amalgamation of Maxwells law of total currents with Ampères circuital law, for his original text on force, see, On Physical Lines of Force. For his original text on dynamics, see, A Dynamical Theory of the Electromagnetic Field, eighteen of the twenty original Maxwells equations can be vectorized into 6 equations. Each vectorized equation represents 3 original equations in component form, including the other two equations, in modern vector notation, they can form a set of eight equations. J is the current density. ρ is the charge density. F is the force per unit charge, σ is the electrical conductivity. ∇ is the vector operator del. This means that equation D is effectively the Lorentz force and this equation first appeared at equation in On Physical Lines of Force quite some time before Lorentz thought of it. In the modern age, the force equations described by Hendrik Lorentz are placed alongside Maxwells equations as an additional electromagnetic equation that is not included as part of the set. When Maxwell derives the electromagnetic wave equation, he uses equation D as opposed to using Faradays law of induction as in modern textbooks. Maxwell however drops the μ term from equation D when he is deriving the electromagnetic wave equation and he obtained a wave equation with a speed in close agreement to experimental determinations of the speed of light. Maxwells equations can also be derived by extending general relativity into five physical dimensions, a Treatise on Electricity and Magnetism On Physical Lines of Force Maxwell, James C
32.
Electric force
–
Coulombs law, or Coulombs inverse-square law, is a law of physics that describes force interacting between static electrically charged particles. The force of interaction between the charges is attractive if the charges have opposite signs and repulsive if like-signed, the law was first published in 1784 by French physicist Charles Augustin de Coulomb and was essential to the development of the theory of electromagnetism. It is analogous to Isaac Newtons inverse-square law of universal gravitation, Coulombs law can be used to derive Gausss law, and vice versa. The law has been tested extensively, and all observations have upheld the laws principle, ancient cultures around the Mediterranean knew that certain objects, such as rods of amber, could be rubbed with cats fur to attract light objects like feathers. Thales was incorrect in believing the attraction was due to a magnetic effect and he coined the New Latin word electricus to refer to the property of attracting small objects after being rubbed. This association gave rise to the English words electric and electricity, however, he did not generalize or elaborate on this. In 1767, he conjectured that the force between charges varied as the square of the distance. In 1769, Scottish physicist John Robison announced that, according to his measurements, in the early 1770s, the dependence of the force between charged bodies upon both distance and charge had already been discovered, but not published, by Henry Cavendish of England. Finally, in 1785, the French physicist Charles-Augustin de Coulomb published his first three reports of electricity and magnetism where he stated his law and this publication was essential to the development of the theory of electromagnetism. The torsion balance consists of a bar suspended from its middle by a thin fiber, the fiber acts as a very weak torsion spring. In Coulombs experiment, the balance was an insulating rod with a metal-coated ball attached to one end. The ball was charged with a charge of static electricity. The two charged balls repelled one another, twisting the fiber through an angle, which could be read from a scale on the instrument. By knowing how much force it took to twist the fiber through a given angle, the force is along the straight line joining them. If the two charges have the sign, the electrostatic force between them is repulsive, if they have different signs, the force between them is attractive. Coulombs law can also be stated as a mathematical expression. The vector form of the equation calculates the force F1 applied on q1 by q2, if r12 is used instead, then the effect on q2 can be found. It can be calculated using Newtons third law, F2 = −F1
33.
Magnetic field
–
A magnetic field is the magnetic effect of electric currents and magnetic materials. The magnetic field at any point is specified by both a direction and a magnitude, as such it is represented by a vector field. The term is used for two distinct but closely related fields denoted by the symbols B and H, where H is measured in units of amperes per meter in the SI, B is measured in teslas and newtons per meter per ampere in the SI. B is most commonly defined in terms of the Lorentz force it exerts on moving electric charges, Magnetic fields can be produced by moving electric charges and the intrinsic magnetic moments of elementary particles associated with a fundamental quantum property, their spin. In quantum physics, the field is quantized and electromagnetic interactions result from the exchange of photons. Magnetic fields are used throughout modern technology, particularly in electrical engineering. The Earth produces its own field, which is important in navigation. Rotating magnetic fields are used in electric motors and generators. Magnetic forces give information about the carriers in a material through the Hall effect. The interaction of magnetic fields in electric devices such as transformers is studied in the discipline of magnetic circuits, noting that the resulting field lines crossed at two points he named those points poles in analogy to Earths poles. He also clearly articulated the principle that magnets always have both a north and south pole, no matter how finely one slices them, almost three centuries later, William Gilbert of Colchester replicated Petrus Peregrinus work and was the first to state explicitly that Earth is a magnet. Published in 1600, Gilberts work, De Magnete, helped to establish magnetism as a science, in 1750, John Michell stated that magnetic poles attract and repel in accordance with an inverse square law. Charles-Augustin de Coulomb experimentally verified this in 1785 and stated explicitly that the north and south poles cannot be separated, building on this force between poles, Siméon Denis Poisson created the first successful model of the magnetic field, which he presented in 1824. In this model, a magnetic H-field is produced by magnetic poles, three discoveries challenged this foundation of magnetism, though. First, in 1819, Hans Christian Ørsted discovered that an electric current generates a magnetic field encircling it, then in 1820, André-Marie Ampère showed that parallel wires having currents in the same direction attract one another. Finally, Jean-Baptiste Biot and Félix Savart discovered the Biot–Savart law in 1820, extending these experiments, Ampère published his own successful model of magnetism in 1825. This has the benefit of explaining why magnetic charge can not be isolated. Also in this work, Ampère introduced the term electrodynamics to describe the relationship between electricity and magnetism, in 1831, Michael Faraday discovered electromagnetic induction when he found that a changing magnetic field generates an encircling electric field
34.
Wave
–
In physics, a wave is an oscillation accompanied by a transfer of energy that travels through a medium. Frequency refers to the addition of time, wave motion transfers energy from one point to another, which displace particles of the transmission medium–that is, with little or no associated mass transport. Waves consist, instead, of oscillations or vibrations, around almost fixed locations, there are two main types of waves. Mechanical waves propagate through a medium, and the substance of this medium is deformed, restoring forces then reverse the deformation. For example, sound waves propagate via air molecules colliding with their neighbors, when the molecules collide, they also bounce away from each other. This keeps the molecules from continuing to travel in the direction of the wave, the second main type, electromagnetic waves, do not require a medium. Instead, they consist of periodic oscillations of electrical and magnetic fields generated by charged particles. These types vary in wavelength, and include radio waves, microwaves, infrared radiation, visible light, ultraviolet radiation, X-rays, waves are described by a wave equation which sets out how the disturbance proceeds over time. The mathematical form of this varies depending on the type of wave. Further, the behavior of particles in quantum mechanics are described by waves, in addition, gravitational waves also travel through space, which are a result of a vibration or movement in gravitational fields. While mechanical waves can be transverse and longitudinal, all electromagnetic waves are transverse in free space. A single, all-encompassing definition for the wave is not straightforward. A vibration can be defined as a back-and-forth motion around a reference value, however, a vibration is not necessarily a wave. An attempt to define the necessary and sufficient characteristics that qualify a phenomenon as a results in a blurred line. The term wave is often understood as referring to a transport of spatial disturbances that are generally not accompanied by a motion of the medium occupying this space as a whole. In a wave, the energy of a vibration is moving away from the source in the form of a disturbance within the surrounding medium and it may appear that the description of waves is closely related to their physical origin for each specific instance of a wave process. For example, acoustics is distinguished from optics in that sound waves are related to a rather than an electromagnetic wave transfer caused by vibration. Concepts such as mass, momentum, inertia, or elasticity and this difference in origin introduces certain wave characteristics particular to the properties of the medium involved
35.
Speed of light
–
The speed of light in vacuum, commonly denoted c, is a universal physical constant important in many areas of physics. Its exact value is 299792458 metres per second, it is exact because the unit of length, the metre, is defined from this constant, according to special relativity, c is the maximum speed at which all matter and hence information in the universe can travel. It is the speed at which all particles and changes of the associated fields travel in vacuum. Such particles and waves travel at c regardless of the motion of the source or the reference frame of the observer. In the theory of relativity, c interrelates space and time, the speed at which light propagates through transparent materials, such as glass or air, is less than c, similarly, the speed of radio waves in wire cables is slower than c. The ratio between c and the speed v at which light travels in a material is called the index n of the material. In communicating with distant space probes, it can take minutes to hours for a message to get from Earth to the spacecraft, the light seen from stars left them many years ago, allowing the study of the history of the universe by looking at distant objects. The finite speed of light limits the theoretical maximum speed of computers. The speed of light can be used time of flight measurements to measure large distances to high precision. Ole Rømer first demonstrated in 1676 that light travels at a speed by studying the apparent motion of Jupiters moon Io. In 1865, James Clerk Maxwell proposed that light was an electromagnetic wave, in 1905, Albert Einstein postulated that the speed of light c with respect to any inertial frame is a constant and is independent of the motion of the light source. He explored the consequences of that postulate by deriving the theory of relativity and in doing so showed that the parameter c had relevance outside of the context of light and electromagnetism. After centuries of increasingly precise measurements, in 1975 the speed of light was known to be 299792458 m/s with a measurement uncertainty of 4 parts per billion. In 1983, the metre was redefined in the International System of Units as the distance travelled by light in vacuum in 1/299792458 of a second, as a result, the numerical value of c in metres per second is now fixed exactly by the definition of the metre. The speed of light in vacuum is usually denoted by a lowercase c, historically, the symbol V was used as an alternative symbol for the speed of light, introduced by James Clerk Maxwell in 1865. In 1856, Wilhelm Eduard Weber and Rudolf Kohlrausch had used c for a different constant later shown to equal √2 times the speed of light in vacuum, in 1894, Paul Drude redefined c with its modern meaning. Einstein used V in his original German-language papers on special relativity in 1905, but in 1907 he switched to c, sometimes c is used for the speed of waves in any material medium, and c0 for the speed of light in vacuum. This article uses c exclusively for the speed of light in vacuum, since 1983, the metre has been defined in the International System of Units as the distance light travels in vacuum in 1⁄299792458 of a second
36.
Radio wave
–
Radio waves are a type of electromagnetic radiation with wavelengths in the electromagnetic spectrum longer than infrared light. Radio waves have frequencies as high as 300 GHz to as low as 3 kHz, though some definitions describe waves above 1 or 3 GHz as microwaves, at 300 GHz, the corresponding wavelength is 1 mm, and at 3 kHz is 100 km. Like all other electromagnetic waves, they travel at the speed of light, naturally occurring radio waves are generated by lightning, or by astronomical objects. Radio waves are generated by radio transmitters and received by radio receivers, the radio spectrum is divided into a number of radio bands on the basis of frequency, allocated to different uses. Radio waves were first predicted by mathematical work done in 1867 by Scottish mathematical physicist James Clerk Maxwell, Maxwell noticed wavelike properties of light and similarities in electrical and magnetic observations. Radio waves were first used for communication in the mid 1890s by Guglielmo Marconi, different frequencies experience different combinations of these phenomena in the Earths atmosphere, making certain radio bands more useful for specific purposes than others. It does not necessarily require a cleared sight path, at lower frequencies radio waves can pass through buildings, foliage and this is the only method of propagation possible at microwave frequencies and above. On the surface of the Earth, line of propagation is limited by the visual horizon to about 40 miles. This is the used by cell phones, cordless phones, walkie-talkies, wireless networks, FM and television broadcasting. Indirect propagation, Radio waves can reach points beyond the line-of-sight by diffraction, diffraction allows a radio wave to bend around obstructions such as a building edge, a vehicle, or a turn in a hall. Radio waves also reflect from surfaces such as walls, floors, ceilings, vehicles and these effects are used in short range radio communication systems. Ground waves allow mediumwave and longwave broadcasting stations to have coverage areas beyond the horizon, the nonzero resistance of the earth absorbs energy from ground waves, so as they propagate the waves lose power and the wavefronts bend over at an angle to the surface. As frequency decreases, the decrease and the achievable range increases. Military very low frequency and extremely low frequency communication systems can communicate over most of the Earth, and with submarines hundreds of feet underwater. Tropospheric propagation, In the VHF and UHF bands, radio waves can travel somewhat beyond the horizon due to refraction in the troposphere. This is due to changes in the index of air with temperature and pressure. At times, radio waves can travel up to 500 -1000 km due to tropospheric ducting and these effects are variable and not as reliable as ionospheric propagation, below. So radio waves directed at an angle into the sky can return to Earth beyond the horizon, by using multiple skips communication at intercontinental distances can be achieved
37.
Kinetic theory of gases
–
Kinetic theory explains macroscopic properties of gases, such as pressure, temperature, viscosity, thermal conductivity, and volume, by considering their molecular composition and motion. The theory posits that gas pressure is due to the impacts, on the walls of a container, Kinetic theory defines temperature in its own way, not identical with the thermodynamic definition. Under a microscope, the making up a liquid are too small to be visible. Known as Brownian motion, it directly from collisions between the grains or particles and liquid molecules. As analyzed by Albert Einstein in 1907, this evidence for kinetic theory is generally seen as having confirmed the concrete material existence of atoms. The theory for ideal gases makes the assumptions, The gas consists of very small particles known as molecules. This smallness of their size is such that the volume of the individual gas molecules added up is negligible compared to the volume of the smallest open ball containing all the molecules. This is equivalent to stating that the distance separating the gas particles is large compared to their size. These particles have the same mass, the number of molecules is so large that statistical treatment can be applied. These molecules are in constant, random, and rapid motion, the rapidly moving particles constantly collide among themselves and with the walls of the container. All these collisions are perfectly elastic and this means, the molecules are considered to be perfectly spherical in shape, and elastic in nature. Except during collisions, the interactions among molecules are negligible and this means that the inter-particle distance is much larger than the thermal de Broglie wavelength and the molecules are treated as classical objects. Because of the two, their dynamics can be treated classically. This means that the equations of motion of the molecules are time-reversible, the average kinetic energy of the gas particles depends only on the absolute temperature of the system. The kinetic theory has its own definition of temperature, not identical with the thermodynamic definition, the elapsed time of a collision between a molecule and the containers wall is negligible when compared to the time between successive collisions. Because they have mass, the gas molecules will be affected by gravity, more modern developments relax these assumptions and are based on the Boltzmann equation. These can accurately describe the properties of gases, because they include the volume of the molecules. The necessary assumptions are the absence of quantum effects, molecular chaos, expansions to higher orders in the density are known as virial expansions
38.
Color photography
–
Color photography is photography that uses media capable of reproducing colors. By contrast, black-and-white photography records only a channel of luminance. In color photography, electronic sensors or light-sensitive chemicals record color information at the time of exposure, monochrome images which have been colorized by tinting selected areas by hand or mechanically or with the aid of a computer are colored photographs, not color photographs. Their colors are not dependent on the colors of the objects photographed. Color photography has been the dominant form of photography since the 1970s, Color photography was attempted beginning in the 1840s. Early experiments were directed at finding a substance which would assume the color of the light falling on it. Other experimenters, such as Edmond Becquerel, achieved better results, over the following several decades, renewed experiments along these lines periodically raised hopes and then dashed them, yielding nothing of practical value. Gabriel Lippmann is remembered as the inventor of a method for reproducing colors by photography, based on the interference phenomenon, in 1886 Lippmanns interest had turned to a method of fixing the colors of the solar spectrum on a photographic plate. By April 1892, he was able to report that he had succeeded in producing color images of a glass window, a group of flags, a bowl of oranges topped by a red poppy. He presented his theory of photography using the interference method in two papers to the Academy, one in 1894, the other in 1906. The named colors are somewhat arbitrary divisions imposed on the spectrum of visible light. The test subject was a bow made of ribbon with stripes of colors, apparently including red. Creating colors by mixing colored lights in various proportions is the method of color reproduction. LCD, LED, plasma and CRT color video displays all use this method and this is also known as the RGB color model. In photography, the dye colors are cyan, a greenish-blue which absorbs red, magenta, a purplish-pink which absorbs green, and yellow. The red-filtered image is used to create a dye image, the green-filtered image to create a magenta dye image. When the three dye images are superimposed they form a color image. This is also known as the CMYK color model, most commonly, three pigment images were first created separately by the so-called carbon process and then carefully combined in register
39.
Structural rigidity
–
In discrete geometry and mechanics, structural rigidity is a combinatorial theory for predicting the flexibility of ensembles formed by rigid bodies connected by flexible linkages or hinges. Rigidity is the property of a structure that it does not bend or flex under an applied force, the opposite of rigidity is flexibility. A structure is rigid if it cannot flex, that is, if there is no motion of the structure that preserves the shape of its rigid components. There are two different kinds of rigidity. Finite or macroscopic rigidity means that the structure will not flex, fold, infinitesimal rigidity means that the structure will not flex by even an amount that is too small to be detected even in theory. A rigid graph is an embedding of a graph in a Euclidean space which is structurally rigid and that is, a graph is rigid if the structure formed by replacing the edges by rigid rods and the vertices by flexible hinges is rigid. A graph that is not rigid is called flexible, the latter condition rules out Euclidean congruences such as simple translation and rotation. It is also possible to consider rigidity problems for graphs in which some edges represent compression elements while other edges represent tension elements, a rigid graph with edges of these types forms a mathematical model of a tensegrity structure. The fundamental problem is how to predict the rigidity of a structure by theoretical analysis, key results in this area include the following, In any dimension, the rigidity of rod-and-hinge linkages is described by a matroid. The bases of the rigidity matroid are the Laman graphs. Cauchys theorem states that a convex polyhedron constructed with rigid plates for its faces, connected by hinges along its edges. Flexible polyhedra, non-convex polyhedra that are not rigid, were constructed by Raoul Bricard, Robert Connelly, the bellows conjecture, now proven, states that any continuous motion of a flexible polyhedron must preserve its volume. However, in many simple situations it is not yet always known how to analyze the rigidity of a structure mathematically despite the existence of considerable mathematical theory. One of the founders of the theory of structural rigidity was the great physicist James Clerk Maxwell. The late twentieth century saw an efflorescence of the theory of rigidity. Theory of the equilibrium and deflections of frameworks subjected to the action of forces, in cases in which the framework. Is strengthened by additional connecting pieces, there are, however, six equations of equilibrium of the system which must be fulfilled necessarily by the forces, on account of the equality of action and reaction in each piece. Hence if e== 3s-6, the effect of any eternal force will be definite in producing tensions or pressures in the different pieces, but if e>3s-6, these forces will be indeterminate
40.
Truss
–
In engineering, a truss is a structure that consists of two-force members only, where the members are organized so that the assemblage as a whole behaves as a single object. A two-force member is a component where force is applied to only two points. In this typical context, external forces and reactions to those forces are considered to act only at the nodes and result in forces in the members that are either tensile or compressive. For straight members, moments are explicitly excluded because, and only because, all the joints in a truss are treated as revolutes, as is necessary for the links to be two-force members. A planar truss is one all members and nodes lie within a two dimensional plane, while a space truss has members and nodes that extend into three dimensions. The top beams in a truss are called top chords and are typically in compression, the beams are called bottom chords. The interior beams are called webs, and the areas inside the webs are called panels, Truss derives from the Old French word trousse, from around 1200, which means collection of things bound together. The term truss has often used to describe any assembly of members such as a cruck frame or a couple of rafters. One engineering definition is, A truss is a single plane framework of individual structural member connected at their ends of forms a series of triangle to span a large distance, a truss consists of typically straight members connected at joints, traditionally termed panel points. Trusses are typically composed of triangles because of the stability of that shape. A triangle is the simplest geometric figure that will not change shape when the lengths of the sides are fixed, in comparison, both the angles and the lengths of a four-sided figure must be fixed for it to retain its shape. The joint at which a truss is designed to be supported is commonly referred to as the Munter Point, the simplest form of a truss is one single triangle. This type of truss is seen in a roof consisting of rafters and a ceiling joist. Because of the stability of this shape and the methods of used to calculate the forces within it. The traditional diamond-shape bicycle frame, which utilizes two conjoined triangles, is an example of a simple truss, a planar truss lies in a single plane. Planar trusses are used in parallel to form roofs and bridges. The depth of a truss, or the height between the upper and lower chords, is what makes it an efficient structural form, a solid girder or beam of equal strength would have substantial weight and material cost as compared to a truss. For a given span, a deeper truss will require less material in the chords, an optimum depth of the truss will maximize the efficiency
41.
Theory of relativity
–
The theory of relativity usually encompasses two interrelated theories by Albert Einstein, special relativity and general relativity. Special relativity applies to particles and their interactions, describing all their physical phenomena except gravity. General relativity explains the law of gravitation and its relation to other forces of nature and it applies to the cosmological and astrophysical realm, including astronomy. The theory transformed theoretical physics and astronomy during the 20th century and it introduced concepts including spacetime as a unified entity of space and time, relativity of simultaneity, kinematic and gravitational time dilation, and length contraction. In the field of physics, relativity improved the science of elementary particles and their fundamental interactions, with relativity, cosmology and astrophysics predicted extraordinary astronomical phenomena such as neutron stars, black holes, and gravitational waves. Max Planck, Hermann Minkowski and others did subsequent work, Einstein developed general relativity between 1907 and 1915, with contributions by many others after 1915. The final form of general relativity was published in 1916, the term theory of relativity was based on the expression relative theory used in 1906 by Planck, who emphasized how the theory uses the principle of relativity. In the discussion section of the paper, Alfred Bucherer used for the first time the expression theory of relativity. By the 1920s, the community understood and accepted special relativity. It rapidly became a significant and necessary tool for theorists and experimentalists in the new fields of physics, nuclear physics. By comparison, general relativity did not appear to be as useful and it seemed to offer little potential for experimental test, as most of its assertions were on an astronomical scale. Its mathematics of general relativity seemed difficult and fully understandable only by a number of people. Around 1960, general relativity became central to physics and astronomy, new mathematical techniques to apply to general relativity streamlined calculations and made its concepts more easily visualized. Special relativity is a theory of the structure of spacetime and it was introduced in Einsteins 1905 paper On the Electrodynamics of Moving Bodies. Special relativity is based on two postulates which are contradictory in classical mechanics, The laws of physics are the same for all observers in motion relative to one another. The speed of light in a vacuum is the same for all observers, the resultant theory copes with experiment better than classical mechanics. For instance, postulate 2 explains the results of the Michelson–Morley experiment, moreover, the theory has many surprising and counterintuitive consequences. Some of these are, Relativity of simultaneity, Two events, simultaneous for one observer, time dilation, Moving clocks are measured to tick more slowly than an observers stationary clock
42.
Quantum mechanics
–
Quantum mechanics, including quantum field theory, is a branch of physics which is the fundamental theory of nature at small scales and low energies of atoms and subatomic particles. Classical physics, the physics existing before quantum mechanics, derives from quantum mechanics as an approximation valid only at large scales, early quantum theory was profoundly reconceived in the mid-1920s. The reconceived theory is formulated in various specially developed mathematical formalisms, in one of them, a mathematical function, the wave function, provides information about the probability amplitude of position, momentum, and other physical properties of a particle. In 1803, Thomas Young, an English polymath, performed the famous experiment that he later described in a paper titled On the nature of light. This experiment played a role in the general acceptance of the wave theory of light. In 1838, Michael Faraday discovered cathode rays, Plancks hypothesis that energy is radiated and absorbed in discrete quanta precisely matched the observed patterns of black-body radiation. In 1896, Wilhelm Wien empirically determined a distribution law of black-body radiation, ludwig Boltzmann independently arrived at this result by considerations of Maxwells equations. However, it was only at high frequencies and underestimated the radiance at low frequencies. Later, Planck corrected this model using Boltzmanns statistical interpretation of thermodynamics and proposed what is now called Plancks law, following Max Plancks solution in 1900 to the black-body radiation problem, Albert Einstein offered a quantum-based theory to explain the photoelectric effect. Among the first to study quantum phenomena in nature were Arthur Compton, C. V. Raman, robert Andrews Millikan studied the photoelectric effect experimentally, and Albert Einstein developed a theory for it. In 1913, Peter Debye extended Niels Bohrs theory of structure, introducing elliptical orbits. This phase is known as old quantum theory, according to Planck, each energy element is proportional to its frequency, E = h ν, where h is Plancks constant. Planck cautiously insisted that this was simply an aspect of the processes of absorption and emission of radiation and had nothing to do with the reality of the radiation itself. In fact, he considered his quantum hypothesis a mathematical trick to get the right rather than a sizable discovery. He won the 1921 Nobel Prize in Physics for this work, lower energy/frequency means increased time and vice versa, photons of differing frequencies all deliver the same amount of action, but do so in varying time intervals. High frequency waves are damaging to human tissue because they deliver their action packets concentrated in time, the Copenhagen interpretation of Niels Bohr became widely accepted. In the mid-1920s, developments in mechanics led to its becoming the standard formulation for atomic physics. In the summer of 1925, Bohr and Heisenberg published results that closed the old quantum theory, out of deference to their particle-like behavior in certain processes and measurements, light quanta came to be called photons
43.
John Clerk Maxwell of Middlebie
–
John Clerk of Middlebie FRSE was a Scottish advocate. He was the son of Captain James Clerk and Janet Irving and he studied Law and qualified as an advocate in 1811. He inherited the Middlebie estate near Corsock in Galloway from his grandmother Dorothea Clerk-Maxwell upon her death in 1793 and he built a new house on the estate which he called Glenlair, a name which later became used for the estate itself. He was elected a Fellow of the Royal Society of Edinburgh in 1821, in the 1830s he is recorded as living at 14 India Street in Edinburghs Second New Town, which is where James Clerk-Maxwell was born. He was the brother of Sir George Clerk of Penicuik, and he was married to Frances Hodshon Cay, daughter of Robert Hodshon Cay and Elizabeth Liddell. His children included the mathematical physicist James Clerk-Maxwell
