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Jun Ishiwara
Jun Ishiwara or Atsushi Ishihara (石原 純; January 15, 1881 – January 19, 1947) was a Japanese theoretical physicist, known for his works on the electronic theory of metals, the theory of relativity and quantum theory. Being the only Japanese scientist who made an original contribution to the old quantum theory, in 1915, independently of other scientists, he formulated quantization rules for systems with several degrees of freedom. Biography Jun Ishiwara was born in the family of Christian priest Ryo Ishiwara and Chise Ishiwara. In 1906, he completed his studies at the Department of Theoretical Physics at the University of Tokyo, where he was a student of Hantaro Nagaoka. Since 1908, Ishiwara taught at the Army School of Artillery and Engineers, and in 1911 received the position of Assistant Professor at the College of Science of Tohoku University. From April 1912 to May 1914 he trained in Europe – at the University of Munich, ETH Zurich and Leiden University, where he wo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tokyo
Tokyo (; ja, 東京, , ), officially the Tokyo Metropolis ( ja, 東京都, label=none, ), is the capital and largest city of Japan. Formerly known as Edo, its metropolitan area () is the most populous in the world, with an estimated 37.468 million residents ; the city proper has a population of 13.99 million people. Located at the head of Tokyo Bay, the prefecture forms part of the Kantō region on the central coast of Honshu, Japan's largest island. Tokyo serves as Japan's economic center and is the seat of both the Japanese government and the Emperor of Japan. Originally a fishing village named Edo, the city became politically prominent in 1603, when it became the seat of the Tokugawa shogunate. By the mid-18th century, Edo was one of the most populous cities in the world with a population of over one million people. Following the Meiji Restoration of 1868, the imperial capital in Kyoto was moved to Edo, which was renamed "Tokyo" (). Tokyo was devastate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tanka
is a genre of classical Japanese poetry and one of the major genres of Japanese literature. Etymology Originally, in the time of the ''Man'yōshū'' (latter half of the eighth century AD), the term ''tanka'' was used to distinguish "short poems" from the longer . In the ninth and tenth centuries, however, notably with the compilation of the '' Kokinshū'', the short poem became the dominant form of poetry in Japan, and the originally general word ''waka'' became the standard name for this form. Japanese poet and critic Masaoka Shiki revived the term ''tanka'' in the early twentieth century for his statement that ''waka should be renewed and modernized''. ''Haiku'' is also a term of his invention, used for his revision of standalone hokku, with the same idea. Form Tanka consist of five units (often treated as separate lines when romanized or translated) usually with the following pattern of '' on'' (often treated as, roughly, the number of syllables per unit or line): :5-7-5-7- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
X-ray
An X-ray, or, much less commonly, X-radiation, is a penetrating form of high-energy electromagnetic radiation. Most X-rays have a wavelength ranging from 10 picometers to 10 nanometers, corresponding to frequencies in the range 30 petahertz to 30 exahertz ( to ) and energies in the range 145 eV to 124 keV. X-ray wavelengths are shorter than those of UV rays and typically longer than those of gamma rays. In many languages, X-radiation is referred to as Röntgen radiation, after the German scientist Wilhelm Conrad Röntgen, who discovered it on November 8, 1895. He named it ''X-radiation'' to signify an unknown type of radiation.Novelline, Robert (1997). ''Squire's Fundamentals of Radiology''. Harvard University Press. 5th edition. . Spellings of ''X-ray(s)'' in English include the variants ''x-ray(s)'', ''xray(s)'', and ''X ray(s)''. The most familiar use of X-rays is checking for fractures (broken bones), but X-rays are also used in other ways. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Satyendra Nath Bose
Satyendra Nath Bose (; 1 January 1894 – 4 February 1974) was a Bengali mathematician and physicist specializing in theoretical physics. He is best known for his work on quantum mechanics in the early 1920s, in developing the foundation for Bose statistics and the theory of the Bose condensate. A Fellow of the Royal Society, he was awarded India's second highest civilian award, the Padma Vibhushan, in 1954 by the Government of India. The class of particles that obey Bose statistics, bosons, was named after Bose by Paul Dirac. A polymath, he had a wide range of interests in varied fields, including physics, mathematics, chemistry, biology, mineralogy, philosophy, arts, literature, and music. He served on many research and development committees in sovereign India. Early life Bose was born in Calcutta (now Kolkata), the eldest of seven children in a Bengali Kayastha family. He was the only son, with six sisters after him. His ancestral home was in the village Bara Jagulia, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Louis De Broglie
Louis Victor Pierre Raymond, 7th Duc de Broglie (, also , or ; 15 August 1892 – 19 March 1987) was a French physicist and aristocrat who made groundbreaking contributions to quantum theory. In his 1924 PhD thesis, he postulated the wave nature of electrons and suggested that all matter has wave properties. This concept is known as the de Broglie hypothesis, an example of wave–particle duality, and forms a central part of the theory of quantum mechanics. De Broglie won the Nobel Prize for Physics in 1929, after the wave-like behaviour of matter was first experimentally demonstrated in 1927. The 1925 pilot-wave model, and the wave-like behaviour of particles discovered by de Broglie was used by Erwin Schrödinger in his formulation of wave mechanics.Antony Valentini: ''On the Pilot-Wave Theory of Classical, Quantum and Subquantum Physics'', Ph.D. Thesis, ISAS, Trieste 1992 The pilot-wave model and interpretation was then abandoned, in favor of the quantum formalism, unt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photon
A photon () is an elementary particle that is a quantum of the electromagnetic field, including electromagnetic radiation such as light and radio waves, and the force carrier for the electromagnetic force. Photons are massless, so they always move at the speed of light in vacuum, (or about ). The photon belongs to the class of bosons. As with other elementary particles, photons are best explained by quantum mechanics and exhibit wave–particle duality, their behavior featuring properties of both waves and particles. The modern photon concept originated during the first two decades of the 20th century with the work of Albert Einstein, who built upon the research of Max Planck. While trying to explain how matter and electromagnetic radiation could be in thermal equilibrium with one another, Planck proposed that the energy stored within a material object should be regarded as composed of an integer number of discrete, equal-sized parts. To explain the photoelectric effect, Eins ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Planck's Law
In physics, Planck's law describes the spectral density of electromagnetic radiation emitted by a black body in thermal equilibrium at a given temperature , when there is no net flow of matter or energy between the body and its environment. At the end of the 19th century, physicists were unable to explain why the observed spectrum of black-body radiation, which by then had been accurately measured, diverged significantly at higher frequencies from that predicted by existing theories. In 1900, German physicist Max Planck heuristically derived a formula for the observed spectrum by assuming that a hypothetical electrically charged oscillator in a cavity that contained black-body radiation could only change its energy in a minimal increment, , that was proportional to the frequency of its associated electromagnetic wave. This resolved the problem of the ultraviolet catastrophe predicted by classical physics. This discovery was a pioneering insight of modern physics and is of fundam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maxwell's Equations
Maxwell's equations, or Maxwell–Heaviside equations, are a set of coupled partial differential equations that, together with the Lorentz force law, form the foundation of classical electromagnetism, classical optics, and electric circuits. The equations provide a mathematical model for electric, optical, and radio technologies, such as power generation, electric motors, wireless communication, lenses, radar etc. They describe how electric and magnetic fields are generated by charges, currents, and changes of the fields.''Electric'' and ''magnetic'' fields, according to the theory of relativity, are the components of a single electromagnetic field. The equations are named after the physicist and mathematician James Clerk Maxwell, who, in 1861 and 1862, published an early form of the equations that included the Lorentz force law. Maxwell first used the equations to propose that light is an electromagnetic phenomenon. The modern form of the equations in their most common formul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Speed Of Light
The speed of light in vacuum, commonly denoted , is a universal physical constant that is important in many areas of physics. The speed of light is exactly equal to ). According to the special theory of relativity, is the upper limit for the speed at which conventional matter or energy (and thus any signal carrying information) can travel through space. All forms of electromagnetic radiation, including visible light, travel at the speed of light. For many practical purposes, light and other electromagnetic waves will appear to propagate instantaneously, but for long distances and very sensitive measurements, their finite speed has noticeable effects. Starlight viewed on Earth left the stars many years ago, allowing humans to study the history of the universe by viewing distant objects. When communicating with distant space probes, it can take minutes to hours for signals to travel from Earth to the spacecraft and vice versa. In computing, the speed of light fixes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Max Abraham
Max Abraham (; 26 March 1875 – 16 November 1922) was a German physicist known for his work on electromagnetism and his opposition to the theory of relativity. Biography Abraham was born in Danzig, Imperial Germany (now Gdańsk in Poland) to a family of Jewish merchants. His father was Moritz Abraham and his mother was Selma Moritzsohn. Attending the University of Berlin, he studied under Max Planck. He graduated in 1897. For the next three years, Abraham worked as Planck's assistant. From 1900 to 1909, Abraham worked at Göttingen as a privatdozent, an unpaid lecturing position. Abraham developed his theory of the electron in 1902, in which he hypothesized that the electron was a perfect sphere with a charge divided evenly around its surface. Abraham's model was competing with that developed by Hendrik Lorentz (1899, 1904) and Albert Einstein (1905) which seem to have become more widely accepted; nevertheless, Abraham never gave up his model, since he considered it was bas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
General Theory Of Relativity
General relativity, also known as the general theory of relativity and Einstein's theory of gravity, is the differential geometry, geometric scientific theory, theory of gravitation published by Albert Einstein in 1915 and is the current description of gravitation in modern physics. General theory of relativity, relativity generalizes special relativity and refines Newton's law of universal gravitation, providing a unified description of gravity as a geometric property of space and time in physics, time or four-dimensional space, four-dimensional spacetime. In particular, the ' is directly related to the energy and momentum of whatever matter and radiation are present. The relation is specified by the Einstein field equations, a system of second order partial differential equations. Newton's law of universal gravitation, which describes classical gravity, can be seen as a prediction of general relativity for the almost flat spacetime geometry around stationary mass distribution ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1910s
File:1910s montage.png, From left, clockwise: The Ford Model T is introduced and becomes widespread; The Sinking of the RMS Titanic, sinking of the R.M.S. Titanic, ''RMS Titanic'' causes the deaths of nearly 1,500 people and attracts global and historical attention; Title bar: All the events below are part of World War I (1914–1918); French Army lookout at his observation post in 1917; Russian troops awaiting a German attack; A ration party of the Royal Irish Rifles in a communication trench during the Battle of the Somme; Vladimir Lenin addresses a crowd in the midst of the Russian Revolution, beginning in 1917; A Spanish flu, flu pandemic in 1918 kills tens of millions worldwide., 420px, thumb rect 1 1 199 155 Ford Model T The Ford Model T is an automobile that was produced by Ford Motor Company from October 1, 1908, to May 26, 1927. It is generally regarded as the first affordable automobile, which made car travel available to middle-class Americans. The relati ... rect ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
