1.
State (polity)
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A state is a type of polity that is an organized political community living under a single system of government. States may or may not be sovereign, for instance, federated states are members of a federal union, and may have only partial sovereignty, but are, nonetheless, states. Some states are subject to external sovereignty or hegemony, in which ultimate sovereignty lies in another state, States that are sovereign are known as sovereign states. The term state can also refer to the branches of government within a state, often as a manner of contrasting them with churches. Speakers of American English often use the state and government as synonyms. Many human societies have been governed by states for millennia, over time a variety of different forms developed, employing a variety of justifications of legitimacy for their existence. In the 21st century, the modern nation-state is the predominant form of state to which people are subjected, there is no academic consensus on the most appropriate definition of the state. The term state refers to a set of different, but interrelated and often overlapping, general categories of state institutions include administrative bureaucracies, legal systems, and military or religious organizations. Another commonly accepted definition of the state is the one given at the Montevideo Convention on Rights, according to the Oxford English Dictionary, a state is a. an organized political community under one government, a commonwealth, a nation. B. such a community forming part of a federal republic, confounding the definition problem is that state and government are often used as synonyms in common conversation and even some academic discourse. According to this schema, the states are nonphysical persons of international law. The relationship between a government and its state is one of representation and authorized agency, States may be classified as sovereign if they are not dependent on, or subject to any other power or state. Other states are subject to external sovereignty or hegemony where ultimate sovereignty lies in another state, many states are federated states which participate in a federal union. A federated state is a territorial and constitutional community forming part of a federation, such states differ from sovereign states in that they have transferred a portion of their sovereign powers to a federal government. One can commonly and sometimes readily classify states according to their apparent make-up or focus, the concept of the nation-state, theoretically or ideally co-terminous with a nation, became very popular by the 20th century in Europe, but occurred rarely elsewhere or at other times. Imperial states have sometimes promoted notions of racial superiority, the concept of temple states centred on religious shrines occurs in some discussions of the ancient world. To some extent, urban secession, the creation of a new city-state, a state can be distinguished from a government. The government is the group of people, the administrative bureaucracy that controls the state apparatus at a given time
2.
Matter
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All the everyday objects that we can bump into, touch or squeeze are ultimately composed of atoms. This ordinary atomic matter is in turn made up of interacting subatomic particles—usually a nucleus of protons and neutrons, typically, science considers these composite particles matter because they have both rest mass and volume. By contrast, massless particles, such as photons, are not considered matter, however, not all particles with rest mass have a classical volume, since fundamental particles such as quarks and leptons are considered point particles with no effective size or volume. Nevertheless, quarks and leptons together make up ordinary matter, Matter exists in states, the classical solid, liquid, and gas, as well as the more exotic plasma, Bose–Einstein condensates, fermionic condensates, and quark–gluon plasma. For much of the history of the natural sciences people have contemplated the nature of matter. The idea that matter was built of discrete building blocks, the so-called particulate theory of matter, was first put forward by the Greek philosophers Leucippus and Democritus, Matter should not be confused with mass, as the two are not the same in modern physics. Matter is itself a physical substance of which systems may be composed, while mass is not a substance, while there are different views on what should be considered matter, the mass of a substance or system is the same irrespective of any such definition of matter. Another difference is that matter has an opposite called antimatter, antimatter has the same mass property as its normal matter counterpart. Different fields of use the term matter in different, and sometimes incompatible. Some of these ways are based on loose historical meanings, from a time there was no reason to distinguish mass from simply a quantity of matter. As such, there is no universally agreed scientific meaning of the word matter. Scientifically, the mass is well-defined, but matter can be defined in several ways. Sometimes in the field of matter is simply equated with particles that exhibit rest mass, such as quarks. However, in physics and chemistry, matter exhibits both wave-like and particle-like properties, the so-called wave–particle duality. A definition of based on its physical and chemical structure is. Such atomic matter is sometimes termed ordinary matter. As an example, deoxyribonucleic acid molecules are matter under this definition because they are made of atoms and this definition can extend to include charged atoms and molecules, so as to include plasmas and electrolytes, which are not obviously included in the atoms definition. Alternatively, one can adopt the protons, neutrons, and electrons definition, at a microscopic level, the constituent particles of matter such as protons, neutrons, and electrons obey the laws of quantum mechanics and exhibit wave–particle duality
3.
Solid
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Solid is one of the four fundamental states of matter. It is characterized by structural rigidity and resistance to changes of shape or volume, unlike a liquid, a solid object does not flow to take on the shape of its container, nor does it expand to fill the entire volume available to it like a gas does. The atoms in a solid are tightly bound to other, either in a regular geometric lattice or irregularly. The branch of physics deals with solids is called solid-state physics. Materials science is concerned with the physical and chemical properties of solids. Solid-state chemistry is concerned with the synthesis of novel materials, as well as the science of identification. The atoms, molecules or ions which make up solids may be arranged in a repeating pattern. Materials whose constituents are arranged in a regular pattern are known as crystals, in some cases, the regular ordering can continue unbroken over a large scale, for example diamonds, where each diamond is a single crystal. Almost all common metals, and many ceramics, are polycrystalline, in other materials, there is no long-range order in the position of the atoms. These solids are known as amorphous solids, examples include polystyrene, whether a solid is crystalline or amorphous depends on the material involved, and the conditions in which it was formed. Solids which are formed by slow cooling will tend to be crystalline, likewise, the specific crystal structure adopted by a crystalline solid depends on the material involved and on how it was formed. While many common objects, such as an ice cube or a coin, are chemically identical throughout, for example, a typical rock is an aggregate of several different minerals and mineraloids, with no specific chemical composition. Wood is an organic material consisting primarily of cellulose fibers embedded in a matrix of organic lignin. In materials science, composites of more than one constituent material can be designed to have desired properties, the forces between the atoms in a solid can take a variety of forms. For example, a crystal of sodium chloride is made up of sodium and chlorine. In diamond or silicon, the atoms share electrons and form covalent bonds, in metals, electrons are shared in metallic bonding. Some solids, particularly most organic compounds, are together with van der Waals forces resulting from the polarization of the electronic charge cloud on each molecule. The dissimilarities between the types of solid result from the differences between their bonding, metals typically are strong, dense, and good conductors of both electricity and heat
4.
Quantum mechanics
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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
5.
Crystallography
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Crystallography is the experimental science of determining the arrangement of atoms in the crystalline solids. The word crystallography derives from the Greek words crystallon cold drop, frozen drop, with its meaning extending to all solids with some degree of transparency, and graphein to write. In July 2012, the United Nations recognised the importance of the science of crystallography by proclaiming that 2014 would be the International Year of Crystallography, X-ray crystallography is used to determine the structure of large biomolecules such as proteins. Before the development of X-ray diffraction crystallography, the study of crystals was based on measurements of their geometry. This involved measuring the angles of crystal faces relative to other and to theoretical reference axes. This physical measurement is carried out using a goniometer, the position in 3D space of each crystal face is plotted on a stereographic net such as a Wulff net or Lambert net. The pole to face is plotted on the net. Each point is labelled with its Miller index, the final plot allows the symmetry of the crystal to be established. Crystallographic methods now depend on analysis of the patterns of a sample targeted by a beam of some type. X-rays are most commonly used, other beams used include electrons or neutrons and this is facilitated by the wave properties of the particles. Crystallographers often explicitly state the type of beam used, as in the terms X-ray crystallography and these three types of radiation interact with the specimen in different ways. X-rays interact with the distribution of electrons in the sample. Electrons are charged particles and therefore interact with the charge distribution of both the atomic nuclei and the electrons of the sample. Neutrons are scattered by the atomic nuclei through the nuclear forces, but in addition. They are therefore also scattered by magnetic fields, when neutrons are scattered from hydrogen-containing materials, they produce diffraction patterns with high noise levels. However, the material can sometimes be treated to substitute deuterium for hydrogen, because of these different forms of interaction, the three types of radiation are suitable for different crystallographic studies. An image of an object is made using a lens to focus the beam. However, the wavelength of light is three orders of magnitude longer than the length of typical atomic bonds and atoms themselves
6.
Electromagnetism
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Electromagnetism is a branch of physics involving the study of the electromagnetic force, a type of physical interaction that occurs between electrically charged particles. The electromagnetic force usually exhibits electromagnetic fields such as fields, magnetic fields. The other three fundamental interactions are the interaction, the weak interaction, and gravitation. The word electromagnetism is a form of two Greek terms, ἤλεκτρον, ēlektron, amber, and μαγνῆτις λίθος magnētis lithos, which means magnesian stone. The electromagnetic force plays a role in determining the internal properties of most objects encountered in daily life. Ordinary matter takes its form as a result of forces between individual atoms and molecules in matter, and is a manifestation of the electromagnetic force. Electrons are bound by the force to atomic nuclei, and their orbital shapes. The electromagnetic force governs the processes involved in chemistry, which arise from interactions between the electrons of neighboring atoms, there are numerous mathematical descriptions of the electromagnetic field. In classical electrodynamics, electric fields are described as electric potential, although electromagnetism is considered one of the four fundamental forces, at high energy the weak force and electromagnetic force are unified as a single electroweak force. In the history of the universe, during the epoch the unified force broke into the two separate forces as the universe cooled. Originally, electricity and magnetism were considered to be two separate forces, Magnetic poles attract or repel one another in a manner similar to positive and negative charges and always exist as pairs, every north pole is yoked to a south pole. An electric current inside a wire creates a corresponding magnetic field outside the wire. Its direction depends on the direction of the current in the wire. A current is induced in a loop of wire when it is moved toward or away from a field, or a magnet is moved towards or away from it. While preparing for a lecture on 21 April 1820, Hans Christian Ørsted made a surprising observation. As he was setting up his materials, he noticed a compass needle deflected away from north when the electric current from the battery he was using was switched on. At the time of discovery, Ørsted did not suggest any explanation of the phenomenon. However, three later he began more intensive investigations
7.
Metallurgy
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The production of metals involves the processing of ores to extract the metal they contain, and the mixture of metals, sometimes with other elements, to produce alloys. Metallurgy is distinguished from the craft of metalworking, although metalworking relies on metallurgy, as medicine relies on medical science, Metallurgy is subdivided into ferrous metallurgy and non-ferrous metallurgy or colored metallurgy. Ferrous metallurgy involves processes and alloys based on iron while non-ferrous metallurgy involves processes, the production of ferrous metals accounts for 95 percent of world metal production. The roots of metallurgy derive from Ancient Greek, μεταλλουργός, metallourgós, worker in metal, from μέταλλον, métallon, metal + ἔργον, érgon, in the late 19th century it was extended to the more general scientific study of metals, alloys, and related processes. In English, the pronunciation is the more common one in the UK. The /ˈmetələrdʒi/ pronunciation is the common one in the USA. The earliest recorded metal employed by humans appears to be gold, small amounts of natural gold have been found in Spanish caves used during the late Paleolithic period, c.40,000 BC. Silver, copper, tin and meteoric iron can also be found in native form, egyptian weapons made from meteoric iron in about 3000 BC were highly prized as daggers from heaven. Certain metals, notably tin, lead and copper, can be recovered from their ores by simply heating the rocks in a fire or blast furnace, a process known as smelting. The first evidence of this extractive metallurgy dates from the 5th and 6th millennia BC and was found in the sites of Majdanpek, Yarmovac and Plocnik. To date, the earliest evidence of copper smelting is found at the Belovode site, other signs of early metals are found from the third millennium BC in places like Palmela, Los Millares, and Stonehenge. However, the ultimate beginnings cannot be ascertained and new discoveries are both continuous and ongoing. These first metals were single ones or as found, about 3500 BC, it was discovered that by combining copper and tin, a superior metal could be made, an alloy called bronze, representing a major technological shift known as the Bronze Age. The extraction of iron from its ore into a metal is much more difficult than for copper or tin. The process appears to have been invented by the Hittites in about 1200 BC, the secret of extracting and working iron was a key factor in the success of the Philistines. Historical developments in ferrous metallurgy can be found in a variety of past cultures. A 16th century book by Georg Agricola called De re metallica describes the highly developed and complex processes of mining metal ores, metal extraction, Agricola has been described as the father of metallurgy. Extractive metallurgy is the practice of removing valuable metals from an ore, in order to convert a metal oxide or sulphide to a purer metal, the ore must be reduced physically, chemically, or electrolytically
8.
Condensed matter physics
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Condensed matter physics is a branch of physics that deals with the physical properties of condensed phases of matter, where particles adhere to each other. Condensed matter physicists seek to understand the behavior of these phases by using physical laws, in particular, they include the laws of quantum mechanics, electromagnetism and statistical mechanics. The field overlaps with chemistry, materials science, and nanotechnology, the theoretical physics of condensed matter shares important concepts and methods with that of particle physics and nuclear physics. A variety of topics in physics such as crystallography, metallurgy, elasticity, magnetism, etc. were treated as distinct areas until the 1940s, when they were grouped together as solid state physics. Around the 1960s, the study of properties of liquids was added to this list, forming the basis for the new. The Bell Telephone Laboratories was one of the first institutes to conduct a program in condensed matter physics. References to condensed state can be traced to earlier sources, as a matter of fact, it would be more correct to unify them under the title of condensed bodies. One of the first studies of condensed states of matter was by English chemist Humphry Davy, Davy observed that of the forty chemical elements known at the time, twenty-six had metallic properties such as lustre, ductility and high electrical and thermal conductivity. This indicated that the atoms in John Daltons atomic theory were not indivisible as Dalton claimed, Davy further claimed that elements that were then believed to be gases, such as nitrogen and hydrogen could be liquefied under the right conditions and would then behave as metals. In 1823, Michael Faraday, then an assistant in Davys lab, successfully liquefied chlorine and went on to all known gaseous elements, except for nitrogen, hydrogen. By 1908, James Dewar and Heike Kamerlingh Onnes were successfully able to hydrogen and then newly discovered helium. Paul Drude in 1900 proposed the first theoretical model for an electron moving through a metallic solid. Drudes model described properties of metals in terms of a gas of free electrons, the phenomenon completely surprised the best theoretical physicists of the time, and it remained unexplained for several decades. Drudes classical model was augmented by Wolfgang Pauli, Arnold Sommerfeld, Felix Bloch, Pauli realized that the free electrons in metal must obey the Fermi–Dirac statistics. Using this idea, he developed the theory of paramagnetism in 1926, shortly after, Sommerfeld incorporated the Fermi–Dirac statistics into the free electron model and made it better able to explain the heat capacity. Two years later, Bloch used quantum mechanics to describe the motion of an electron in a periodic lattice. Magnetism as a property of matter has been known in China since 4000 BC, Pierre Curie studied the dependence of magnetization on temperature and discovered the Curie point phase transition in ferromagnetic materials. In 1906, Pierre Weiss introduced the concept of magnetic domains to explain the properties of ferromagnets
9.
Atom
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An atom is the smallest constituent unit of ordinary matter that has the properties of a chemical element. Every solid, liquid, gas, and plasma is composed of neutral or ionized atoms, Atoms are very small, typical sizes are around 100 picometers. Atoms are small enough that attempting to predict their behavior using classical physics - as if they were billiard balls, through the development of physics, atomic models have incorporated quantum principles to better explain and predict the behavior. Every atom is composed of a nucleus and one or more bound to the nucleus. The nucleus is made of one or more protons and typically a number of neutrons. Protons and neutrons are called nucleons, more than 99. 94% of an atoms mass is in the nucleus. The protons have an electric charge, the electrons have a negative electric charge. If the number of protons and electrons are equal, that atom is electrically neutral, if an atom has more or fewer electrons than protons, then it has an overall negative or positive charge, respectively, and it is called an ion. The electrons of an atom are attracted to the protons in a nucleus by this electromagnetic force. The number of protons in the nucleus defines to what chemical element the atom belongs, for example, the number of neutrons defines the isotope of the element. The number of influences the magnetic properties of an atom. Atoms can attach to one or more other atoms by chemical bonds to form compounds such as molecules. The ability of atoms to associate and dissociate is responsible for most of the changes observed in nature. The idea that matter is made up of units is a very old idea, appearing in many ancient cultures such as Greece. The word atom was coined by ancient Greek philosophers, however, these ideas were founded in philosophical and theological reasoning rather than evidence and experimentation. As a result, their views on what look like. They also could not convince everybody, so atomism was but one of a number of competing theories on the nature of matter. It was not until the 19th century that the idea was embraced and refined by scientists, in the early 1800s, John Dalton used the concept of atoms to explain why elements always react in ratios of small whole numbers
10.
Materials science
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The interdisciplinary field of materials science, also commonly termed materials science and engineering, involves the discovery and design of new materials, with an emphasis on solids. Materials science still incorporates elements of physics, chemistry, and engineering, as such, the field was long considered by academic institutions as a sub-field of these related fields. Materials science is a syncretic discipline hybridizing metallurgy, ceramics, solid-state physics and it is the first example of a new academic discipline emerging by fusion rather than fission. Many of the most pressing scientific problems humans currently face are due to the limits of the materials that are available, thus, breakthroughs in materials science are likely to affect the future of technology significantly. Materials scientists emphasize understanding how the history of a material influences its structure, the understanding of processing-structure-properties relationships is called the § materials paradigm. This paradigm is used to advance understanding in a variety of areas, including nanotechnology, biomaterials. Such investigations are key to understanding, for example, the causes of various accidents and incidents. The material of choice of a given era is often a defining point, phrases such as Stone Age, Bronze Age, Iron Age, and Steel Age are great examples. Originally deriving from the manufacture of ceramics and its putative derivative metallurgy, materials science is one of the oldest forms of engineering, modern materials science evolved directly from metallurgy, which itself evolved from mining and ceramics and the use of fire. Materials science has driven, and been driven by, the development of technologies such as rubbers, plastics, semiconductors. Before the 1960s, many materials science departments were named metallurgy departments, reflecting the 19th, a material is defined as a substance that is intended to be used for certain applications. There are a myriad of materials around us—they can be found in anything from buildings to spacecraft, Materials can generally be divided into two classes, crystalline and non-crystalline. The traditional examples of materials are metals, semiconductors, ceramics, New and advanced materials that are being developed include nanomaterials and biomaterials, etc. The basis of science involves studying the structure of materials. Once a materials scientist knows about this structure-property correlation, they can go on to study the relative performance of a material in a given application. The major determinants of the structure of a material and thus of its properties are its constituent chemical elements and these characteristics, taken together and related through the laws of thermodynamics and kinetics, govern a materials microstructure, and thus its properties. As mentioned above, structure is one of the most important components of the field of materials science, Materials science examines the structure of materials from the atomic scale, all the way up to the macro scale. Characterization is the way materials scientists examine the structure of a material, structure is studied at various levels, as detailed below
