1.
Nuclear fission
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In nuclear physics and nuclear chemistry, nuclear fission is either a nuclear reaction or a radioactive decay process in which the nucleus of an atom splits into smaller parts. The fission process often produces free neutrons and gamma photons, Frisch named the process by analogy with biological fission of living cells. It is a reaction which can release large amounts of energy both as electromagnetic radiation and as kinetic energy of the fragments. In order for fission to produce energy, the binding energy of the resulting elements must be less negative than that of the starting element. Fission is a form of nuclear transmutation because the fragments are not the same element as the original atom. The two nuclei produced are most often of comparable but slightly different sizes, typically with a ratio of products of about 3 to 2. Most fissions are binary fissions, but occasionally, three positively charged fragments are produced, in a ternary fission, the smallest of these fragments in ternary processes ranges in size from a proton to an argon nucleus. Nuclear fission produces energy for power and drives the explosion of nuclear weapons. Both uses are possible because certain substances called nuclear fuels undergo fission when struck by fission neutrons and this makes possible a self-sustaining nuclear chain reaction that releases energy at a controlled rate in a nuclear reactor or at a very rapid uncontrolled rate in a nuclear weapon. Nuclear fission can occur without neutron bombardment as a type of radioactive decay and this type of fission is rare except in a few heavy isotopes. In engineered nuclear devices, essentially all nuclear fission occurs as a nuclear reaction — a bombardment-driven process that results from the collision of two subatomic particles, in nuclear reactions, a subatomic particle collides with an atomic nucleus and causes changes to it. Nuclear reactions are driven by the mechanics of bombardment, not by the relatively constant exponential decay. Many types of reactions are currently known. Nuclear fission differs importantly from other types of reactions, in that it can be amplified. In such a reaction, free neutrons released by each fission event can trigger yet more events, the chemical element isotopes that can sustain a fission chain reaction are called nuclear fuels, and are said to be fissile. The most common nuclear fuels are 235U and 239Pu and these fuels break apart into a bimodal range of chemical elements with atomic masses centering near 95 and 135 u. Most nuclear fuels undergo spontaneous fission only very slowly, decaying instead mainly via an alpha-beta decay chain over periods of millennia to eons. In a nuclear reactor or nuclear weapon, the majority of fission events are induced by bombardment with another particle, a neutron
2.
Germany
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Germany, officially the Federal Republic of Germany, is a federal parliamentary republic in central-western Europe. It includes 16 constituent states, covers an area of 357,021 square kilometres, with about 82 million inhabitants, Germany is the most populous member state of the European Union. After the United States, it is the second most popular destination in the world. Germanys capital and largest metropolis is Berlin, while its largest conurbation is the Ruhr, other major cities include Hamburg, Munich, Cologne, Frankfurt, Stuttgart, Düsseldorf and Leipzig. Various Germanic tribes have inhabited the northern parts of modern Germany since classical antiquity, a region named Germania was documented before 100 AD. During the Migration Period the Germanic tribes expanded southward, beginning in the 10th century, German territories formed a central part of the Holy Roman Empire. During the 16th century, northern German regions became the centre of the Protestant Reformation, in 1871, Germany became a nation state when most of the German states unified into the Prussian-dominated German Empire. After World War I and the German Revolution of 1918–1919, the Empire was replaced by the parliamentary Weimar Republic, the establishment of the national socialist dictatorship in 1933 led to World War II and the Holocaust. After a period of Allied occupation, two German states were founded, the Federal Republic of Germany and the German Democratic Republic, in 1990, the country was reunified. In the 21st century, Germany is a power and has the worlds fourth-largest economy by nominal GDP. As a global leader in industrial and technological sectors, it is both the worlds third-largest exporter and importer of goods. Germany is a country with a very high standard of living sustained by a skilled. It upholds a social security and universal health system, environmental protection. Germany was a member of the European Economic Community in 1957. It is part of the Schengen Area, and became a co-founder of the Eurozone in 1999, Germany is a member of the United Nations, NATO, the G8, the G20, and the OECD. The national military expenditure is the 9th highest in the world, the English word Germany derives from the Latin Germania, which came into use after Julius Caesar adopted it for the peoples east of the Rhine. This in turn descends from Proto-Germanic *þiudiskaz popular, derived from *þeudō, descended from Proto-Indo-European *tewtéh₂- people, the discovery of the Mauer 1 mandible shows that ancient humans were present in Germany at least 600,000 years ago. The oldest complete hunting weapons found anywhere in the world were discovered in a mine in Schöningen where three 380, 000-year-old wooden javelins were unearthed
3.
Nazi Germany
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Nazi Germany is the common English name for the period in German history from 1933 to 1945, when Germany was governed by a dictatorship under the control of Adolf Hitler and the Nazi Party. Under Hitlers rule, Germany was transformed into a fascist state in which the Nazi Party took totalitarian control over all aspects of life. The official name of the state was Deutsches Reich from 1933 to 1943, the period is also known under the names the Third Reich and the National Socialist Period. The Nazi regime came to an end after the Allied Powers defeated Germany in May 1945, Hitler was appointed Chancellor of Germany by the President of the Weimar Republic Paul von Hindenburg on 30 January 1933. The Nazi Party then began to eliminate all opposition and consolidate its power. Hindenburg died on 2 August 1934, and Hitler became dictator of Germany by merging the powers and offices of the Chancellery, a national referendum held 19 August 1934 confirmed Hitler as sole Führer of Germany. All power was centralised in Hitlers person, and his word became above all laws, the government was not a coordinated, co-operating body, but a collection of factions struggling for power and Hitlers favour. In the midst of the Great Depression, the Nazis restored economic stability and ended mass unemployment using heavy military spending, extensive public works were undertaken, including the construction of Autobahnen. The return to economic stability boosted the regimes popularity, racism, especially antisemitism, was a central feature of the regime. The Germanic peoples were considered by the Nazis to be the purest branch of the Aryan race, millions of Jews and other peoples deemed undesirable by the state were murdered in the Holocaust. Opposition to Hitlers rule was ruthlessly suppressed, members of the liberal, socialist, and communist opposition were killed, imprisoned, or exiled. The Christian churches were also oppressed, with many leaders imprisoned, education focused on racial biology, population policy, and fitness for military service. Career and educational opportunities for women were curtailed, recreation and tourism were organised via the Strength Through Joy program, and the 1936 Summer Olympics showcased the Third Reich on the international stage. Propaganda minister Joseph Goebbels made effective use of film, mass rallies, the government controlled artistic expression, promoting specific art forms and banning or discouraging others. Beginning in the late 1930s, Nazi Germany made increasingly aggressive territorial demands and it seized Austria and Czechoslovakia in 1938 and 1939. Hitler made a pact with Joseph Stalin and invaded Poland in September 1939. In alliance with Italy and smaller Axis powers, Germany conquered most of Europe by 1940, reichskommissariats took control of conquered areas, and a German administration was established in what was left of Poland. Jews and others deemed undesirable were imprisoned, murdered in Nazi concentration camps and extermination camps, following the German invasion of the Soviet Union in 1941, the tide gradually turned against the Nazis, who suffered major military defeats in 1943
4.
Dahlem (Berlin)
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Dahlem is a locality of the Steglitz-Zehlendorf borough in southwestern Berlin. Until Berlins 2001 administrative reform it was a part of the borough of Zehlendorf. Dahlem is one of the most affluent parts of the city, Dahlem is home to the renowned Freie Universität Berlin with its Philological Library by Norman Foster as an important local landmark. Several other research institutions, the Berlin Botanical Garden and many museums are located there, although Dahlem has a reputation of an idyllic and quiet area, it is very busy with students arriving by U-Bahn on weekdays. The western part of the locality includes parts of the Grunewald forest, the first written account of Dahlem dates to the year 1275. The history of the village is connected to the Dahlem Demesne first mentioned in 1450 and its estates were sold to the state of Prussia in 1841 and developed by dividing it into lots for building villas and mansions. The Demesne buildings today house a farm and an agricultural open-air museum. In 1920 the village was amalgamated into Greater Berlin, from 1931 on Martin Niemöller, a leader of the Confessing Church, was pastor of the United Protestant Sankt-Annen-Kirche until he was arrested by the Nazis in 1937. During the Cold War Dahlem belonged to the American Sector of West Berlin, from 1945 to 1991 the seat of the Allied Kommandatura of Berlin was in Dahlem on Kaiserswerther Straße. Today it serves as the office for the president of the local university, until 1994, the headquarters of the United States Army Berlin command and the Berlin Brigade were located on Clayallee street. Parts of the building are used by the Embassy of the United States in Berlin. The former library and Outpost theater across the street today house the Allied Museum, the newly founded university should uphold the traditional values of academic freedom and the educational ideal proposed by Wilhelm von Humboldt. Rudi Dutschke, spokesman of the German student movement in the 1960s, is buried at the cemetery of the Sankt-Annen-Kirche, stations in Dahlem include Breitenbachplatz, Podbielskiallee, Dahlem-Dorf, Thielplatz and Oskar-Helene-Heim. Berlin-Verlag, ISBN 3-87061-155-3 Media related to Dahlem at Wikimedia Commons
5.
Wilhelm II, German Emperor
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Wilhelm II or William II was the last German Emperor and King of Prussia, ruling the German Empire and the Kingdom of Prussia from 15 June 1888 to 9 November 1918. He was the eldest grandchild of the British Queen Victoria and related to many monarchs and his leading generals, Paul von Hindenburg and Erich Ludendorff, dictated policy during the First World War with little regard for the civilian government. An ineffective war-time leader, he lost the support of the army, abdicated in November 1918, and fled to exile in the Netherlands. Wilhelm was born on 27 January 1859 at the Crown Princes Palace, Berlin to Prince Frederick William of Prussia and his wife, Victoria, Princess Royal, the eldest daughter of Britains Queen Victoria. At the time of his birth, his great-uncle Frederick William IV was king of Prussia, a traumatic breech birth left him with a withered left arm due to Erbs palsy, which he tried with some success to conceal. His left arm was about 6 inches shorter than his right arm, historians have suggested that this disability affected his emotional development. In 1863, Wilhelm was taken to England to be present at the wedding of his Uncle Bertie, William attended the ceremony in a Highland costume, complete with a small toy dirk. During the ceremony the four-year-old became restless and his eighteen-year-old uncle Alfred, Duke of Edinburgh, charged with keeping an eye on him, told him to be quiet, but Wilhelm drew his dirk and threatened Alfred. When Alfred attempted to subdue him by force, Wilhelm bit him on the leg and his grandmother, Queen Victoria, missed seeing the fracas, to her Wilhelm remained a clever, dear, good little child, the great favourite of my beloved Vicky. His mother, Vicky, was obsessed with his damaged arm and she blamed herself for the childs handicap and insisted that he become a good rider. The thought that he, as heir to the throne, should not be able to ride was intolerable to her, riding lessons began when Wilhelm was eight and were a matter of endurance for Wilhelm. Over and over, the prince was set on his horse. He fell off time after time but despite his tears was set on its back again, after weeks of this he finally got it right and was able to maintain his balance. Wilhelm, from six years of age, was tutored and heavily influenced by the 39-year-old teacher Georg Hinzpeter, Hinzpeter, he later wrote, was really a good fellow. Whether he was the tutor for me, I dare not decide. The torments inflicted on me, in this riding, must be attributed to my mother. As a teenager he was educated at Kassel at the Friedrichsgymnasium, in January 1877, Wilhelm finished high school and on his eighteenth birthday received as a present from his grandmother, Queen Victoria, the Order of the Garter. After Kassel he spent four terms at the University of Bonn, studying law and he became a member of the exclusive Corps Borussia Bonn
6.
Natural science
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Natural science is a branch of science concerned with the description, prediction, and understanding of natural phenomena, based on observational and empirical evidence. Mechanisms such as review and repeatability of findings are used to try to ensure the validity of scientific advances. Natural science can be divided into two branches, life science and physical science. Physical science is subdivided into branches, including physics, space science, chemistry and these branches of natural science may be further divided into more specialized branches. Modern natural science succeeded more classical approaches to natural philosophy, usually traced to ancient Greece, galileo, Descartes, Francis Bacon, and Newton debated the benefits of using approaches which were more mathematical and more experimental in a methodical way. Still, philosophical perspectives, conjectures, and presuppositions, often overlooked, systematic data collection, including discovery science, succeeded natural history, which emerged in the 16th century by describing and classifying plants, animals, minerals, and so on. Today, natural history suggests observational descriptions aimed at popular audiences, philosophers of science have suggested a number of criteria, including Karl Poppers controversial falsifiability criterion, to help them differentiate scientific endeavors from non-scientific ones. Validity, accuracy, and quality control, such as peer review and this field encompasses a set of disciplines that examines phenomena related to living organisms. The scale of study can range from sub-component biophysics up to complex ecologies, biology is concerned with the characteristics, classification and behaviors of organisms, as well as how species were formed and their interactions with each other and the environment. The biological fields of botany, zoology, and medicine date back to periods of civilization. However, it was not until the 19th century that became a unified science. Once scientists discovered commonalities between all living things, it was decided they were best studied as a whole, modern biology is divided into subdisciplines by the type of organism and by the scale being studied. Molecular biology is the study of the chemistry of life, while cellular biology is the examination of the cell. At a higher level, anatomy and physiology looks at the internal structures, constituting the scientific study of matter at the atomic and molecular scale, chemistry deals primarily with collections of atoms, such as gases, molecules, crystals, and metals. The composition, statistical properties, transformations and reactions of these materials are studied, chemistry also involves understanding the properties and interactions of individual atoms and molecules for use in larger-scale applications. Most chemical processes can be studied directly in a laboratory, using a series of techniques for manipulating materials, chemistry is often called the central science because of its role in connecting the other natural sciences. Early experiments in chemistry had their roots in the system of Alchemy, the science of chemistry began to develop with the work of Robert Boyle, the discoverer of gas, and Antoine Lavoisier, who developed the theory of the Conservation of mass. The success of science led to a complementary chemical industry that now plays a significant role in the world economy
7.
Albert Einstein
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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
8.
Otto Hahn
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Otto Hahn, OBE, ForMemRS was a German chemist and pioneer in the fields of radioactivity and radiochemistry. He was exclusively awarded the Nobel Prize in Chemistry in 1944 for the discovery and he is referred to as the father of nuclear chemistry. Hahn was an opponent of socialism and Jewish persecution by the Nazi Party. Albert Einstein wrote that Hahn was one of the few who stood upright. After World War II, Hahn became a campaigner against the use of nuclear energy as a weapon. He served as the last President of the Kaiser Wilhelm Society in 1946, considered by many to be a model for scholarly excellence and personal integrity, he became one of the most influential and respected citizens of the new Federal Republic of Germany. Hahn was the youngest son of Heinrich Hahn, a glazier and entrepreneur. Together with his brothers Karl, Heiner and Julius, Otto was raised in a sheltered environment, at the age of 15, he began to take a special interest in chemistry, and carried out simple experiments in the laundry room of the family home. His father wanted Otto to study architecture, as he had built or acquired several residential and business properties, in 1897, after taking his Abitur at the Klinger Oberrealschule in Frankfurt, Hahn began to study chemistry and mineralogy at the University of Marburg. His subsidiary subjects were physics and philosophy, Hahn joined the Students Association of Natural Sciences and Medicine, a student fraternity and a forerunner of todays Landsmannschaft Nibelungia. He spent his third and fourth semester studying under Adolf von Baeyer at the University of Munich, in 1901, Hahn received his doctorate in Marburg for a dissertation entitled On Bromine Derivates of Isoeugenol, a topic in classical organic chemistry. Hahns intention had been to work in industry, with this in mind, and also to improve his knowledge of English, he took up a post at University College London in 1904, working under Sir William Ramsay, known for having discovered the inert gases. Here Hahn worked on radiochemistry, at time a very new field. In early 1905, in the course of his work with salts of radium, Hahn discovered a new substance he called radiothorium, Ramsay was very enthused when yet another new element was found in his institute, and he intended to announce the discovery in a correspondingly suitable way. In accordance with tradition this should be done before the committee of the venerable Royal Society, at the session of the Royal Society on the 16 March 1905 Ramsay communicated Hahns discovery of radiothorium, and even the press was interested. The Daily Telegraph informed its readers, A NEW ELEMENT - Very soon the scientific papers will be agog with a new discovery which has added to the many brilliant triumphs of Gower Street. Its activity is at least 250,000 times as great as that of thorium and it gives off a gas, identical with the radioactive emanation from thorium. - The discoverer read a paper on the subject to the Royal Society last week, and this should rank and it was the first of more than 250 scientific publications of Otto Hahn in the field of radiochemistry
9.
Max Planck
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Max Karl Ernst Ludwig Planck, FRS was a German theoretical physicist whose discovery of energy quanta won him the Nobel Prize in Physics in 1918. However, his name is known on a broader academic basis, through the renaming in 1948 of the German scientific institution. The MPS now includes 83 institutions representing a range of scientific directions. Planck came from a traditional, intellectual family and his paternal great-grandfather and grandfather were both theology professors in Göttingen, his father was a law professor in Kiel and Munich. Planck was born in Kiel, Holstein, to Johann Julius Wilhelm Planck and his second wife and he was baptised with the name of Karl Ernst Ludwig Marx Planck, of his given names, Marx was indicated as the primary name. However, by the age of ten he signed with the name Max and he was the 6th child in the family, though two of his siblings were from his fathers first marriage. Among his earliest memories was the marching of Prussian and Austrian troops into Kiel during the Second Schleswig War in 1864 and it was from Müller that Planck first learned the principle of conservation of energy. Planck graduated early, at age 17 and this is how Planck first came in contact with the field of physics. Planck was gifted when it came to music and he took singing lessons and played piano, organ and cello, and composed songs and operas. However, instead of music he chose to study physics, the Munich physics professor Philipp von Jolly advised Planck against going into physics, saying, in this field, almost everything is already discovered, and all that remains is to fill a few holes. Planck replied that he did not wish to discover new things, but only to understand the fundamentals of the field. Under Jollys supervision, Planck performed the experiments of his scientific career, studying the diffusion of hydrogen through heated platinum. In 1877 he went to the Friedrich Wilhelms University in Berlin for a year of study with physicists Hermann von Helmholtz and Gustav Kirchhoff and mathematician Karl Weierstrass. He wrote that Helmholtz was never quite prepared, spoke slowly, miscalculated endlessly and he soon became close friends with Helmholtz. While there he undertook a program of mostly self-study of Clausiuss writings, in October 1878 Planck passed his qualifying exams and in February 1879 defended his dissertation, Über den zweiten Hauptsatz der mechanischen Wärmetheorie. He briefly taught mathematics and physics at his school in Munich. In June 1880, he presented his thesis, Gleichgewichtszustände isotroper Körper in verschiedenen Temperaturen. With the completion of his thesis, Planck became an unpaid private lecturer in Munich
