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Test Theories Of Special Relativity
Test theories of special relativity give a mathematical framework for analyzing results of experiments to verify special relativity. An experiment to test the theory of relativity cannot assume the theory is true, and therefore needs some other framework of assumptions that are wider than those of relativity. For example, a test theory may have a different postulate about light concerning one-way speed of light vs. two-way speed of light, it may have a preferred frame of reference, and may violate Lorentz invariance in many different ways. Test theories predicting different experimental results from Einstein's special relativity, are ''Robertson's test theory (1949)'', and the ''Mansouri–Sexl theory (1977)'' which is equivalent to Robertson's theory. Another, more extensive model is the Standard-Model Extension, which also includes the standard model and general relativity. Robertson–Mansouri–Sexl framework Basic principles Howard Percy Robertson (1949) extended the L ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Test Theory
Test(s), testing, or TEST may refer to: * Test (assessment), an educational assessment intended to measure the respondents' knowledge or other abilities Arts and entertainment * Test (2013 film), ''Test'' (2013 film), an American film * Test (2014 film), ''Test'' (2014 film), a Russian film * Test (2025 film), ''Test'' (2025 film), an Indian sports drama * Test (group), a jazz collective * Tests (album), ''Tests'' (album), a 1998 album by The Microphones * Testing (album), ''Testing'' (album), an album by ASAP Rocky Computing * .test, a reserved top-level domain * Software testing * test (Unix), a Unix command for evaluating conditional expressions * TEST (x86 instruction), an x86 assembly language instruction People * Test (wrestler), ring name for Andrew Martin (1975–2009), Canadian professional wrestler * John Test (1771–1849), American politician * Zack Test (born 1989), American rugby union player Science and technology * Experiment, a procedure carried out in orde ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cosmic Microwave Background Radiation
The cosmic microwave background (CMB, CMBR), or relic radiation, is microwave radiation that fills all space in the observable universe. With a standard optical telescope, the background space between stars and galaxies is almost completely dark. However, a sufficiently sensitive radio telescope detects a faint background glow that is almost isotropic, uniform and is not associated with any star, galaxy, or other astronomical object, object. This glow is strongest in the microwave region of the electromagnetic spectrum. The accidental Discovery of cosmic microwave background radiation, discovery of the CMB in 1965 by American radio astronomers Arno Allan Penzias and Robert Woodrow Wilson was the culmination of work initiated in the 1940s. The CMB is landmark evidence of the Big Bang scientific theory, theory for the origin of the universe. In the Big Bang cosmological models, during the earliest periods, the universe was filled with an Opacity (optics), opaque fog of dense, hot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perth, Western Australia
Perth () is the list of Australian capital cities, capital city of Western Australia. It is the list of cities in Australia by population, fourth-most-populous city in Australia, with a population of over 2.3 million within Greater Perth . The Extremes on Earth#Other places considered the most remote, world's most isolated major city by certain criteria, Perth is part of the South West Land Division of Western Australia, with most of Perth metropolitan region, Perth's metropolitan area on the Swan Coastal Plain between the Indian Ocean and the Darling Scarp. The city has expanded outward from the original British settlements on the Swan River (Western Australia), Swan River, upon which its #Central business district, central business district and port of Fremantle are situated. Perth was founded by James Stirling (Royal Navy officer), Captain James Stirling in 1829 as the administrative centre of the Swan River Colony. The city is situated on the traditional lands of the Whadju ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Berlin
Berlin ( ; ) is the Capital of Germany, capital and largest city of Germany, by both area and List of cities in Germany by population, population. With 3.7 million inhabitants, it has the List of cities in the European Union by population within city limits, highest population within its city limits of any city in the European Union. The city is also one of the states of Germany, being the List of German states by area, third smallest state in the country by area. Berlin is surrounded by the state of Brandenburg, and Brandenburg's capital Potsdam is nearby. The urban area of Berlin has a population of over 4.6 million and is therefore the most populous urban area in Germany. The Berlin/Brandenburg Metropolitan Region, Berlin-Brandenburg capital region has around 6.2 million inhabitants and is Germany's second-largest metropolitan region after the Rhine-Ruhr region, as well as the List of EU metropolitan areas by GDP, fifth-biggest metropolitan region by GDP in the European Union. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CPT Symmetry
Charge, parity, and time reversal symmetry is a fundamental symmetry of physical laws under the simultaneous transformations of charge conjugation (C), parity transformation (P), and time reversal (T). CPT is the only combination of C, P, and T that is observed to be an exact symmetry of nature at the fundamental level. The CPT theorem says that CPT symmetry holds for all physical phenomena, or more precisely, that any Lorentz invariant local quantum field theory with a Hermitian Hamiltonian must have CPT symmetry. In layman terms, this stipulates that an antimatter, mirrored, and time reversed universe would behave exactly the same as our regular universe. History The CPT theorem appeared for the first time, implicitly, in the work of Julian Schwinger in 1951 to prove the connection between spin and statistics. In 1954, Gerhart Lüders and Wolfgang Pauli derived more explicit proofs, so this theorem is sometimes known as the Lüders–Pauli theorem. At about the same t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alan Kostelecký
V. Alan Kostelecký is a theoretical physicist who is a distinguished professor of physics at Indiana University, Bloomington. He is noted for his work on Lorentz symmetry breaking in particle physics. He has been described as the world's leading authority on violations of space-time symmetry. Kostelecký was a student at the International School of Geneva, Switzerland (1965-1973). Subsequently, he began as an undergraduate in biology, switched his degree to chemistry, and eventually switched for the last time to physics and obtained his undergraduate degree in science from Bristol University in 1977, and his Ph.D. in physics from Yale University in 1982. He has been a faculty member at the Indiana University in Bloomington since joining there in 1985. In 1989, Kostelecký and his colleagues demonstrated the existence of an anisotropy in string theory models, and proposed a new version of the Standard Model of particle physics, called the ''Standard-Model Extension'' that catalo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rømer's Determination Of The Speed Of Light
Rømer's determination of the speed of light was the demonstration in 1676 that light has an apprehensible, measurable speed and so does not travel instantaneously. The discovery is usually attributed to Danish astronomer Ole Rømer,There are several alternative spellings of Rømer's surname, including "Roemer", "Rœmer", and "Römer". The Danish "Ole" is sometimes latinized to "Olaus". who was working at the Royal Observatory in Paris at the time. By timing the eclipses of Jupiter's moon Io, Rømer estimated that light would take about 22 minutes to travel a distance equal to the diameter of Earth's orbit around the Sun. Using modern orbits, this would imply a speed of light of 226,663 kilometres per second, 24.4% lower than the true value of 299,792 km/s. In his calculations Rømer used the idea and observations that the apparent time between eclipses would be greater while the Earth is moving further from Jupiter and lesser while moving closer. Rømer's theory was ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Relativistic Doppler Effect
The relativistic Doppler effect is the change in frequency, wavelength and amplitude of light, caused by the relative motion of the source and the observer (as in the classical Doppler effect, first proposed by Christian Doppler in 1842), when taking into account effects described by the special theory of relativity. The relativistic Doppler effect is different from the non-relativistic Doppler effect as the equations include the time dilation effect of special relativity and do not involve the medium of propagation as a reference point. They describe the total difference in observed frequencies and possess the required Lorentz symmetry. Astronomers know of three sources of redshift/blueshift: Doppler shifts; gravitational redshifts (due to light exiting a gravitational field); and cosmological expansion (where space itself stretches). This article concerns itself only with Doppler shifts. Summary of major results In the following table, it is assumed that for \beta = v/c > ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ives–Stilwell Experiment
In physics, the Ives–Stilwell experiment tested the contribution of relativistic time dilation to the Doppler shift of light. The result was in agreement with the formula for the transverse Doppler effect and was the first direct, quantitative confirmation of the time dilation factor. Since then many Ives–Stilwell type experiments have been performed with increased precision. Together with the Michelson–Morley and Kennedy–Thorndike experiments it forms one of the fundamental tests of special relativity theory. Other tests confirming the relativistic Doppler effect are the Mössbauer rotor experiment and modern Ives–Stilwell experiments. Both time dilation and the relativistic Doppler effect were predicted by Albert Einstein in his seminal 1905 paper. Einstein subsequently (1907) suggested an experiment based on the measurement of the relative frequencies of light perceived as arriving from "canal rays" (positive ion beams created by certain types of gas-discharge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kennedy–Thorndike Experiment
The Kennedy–Thorndike experiment, first conducted in 1932 by Roy J. Kennedy and Edward M. Thorndike, is a modified form of the Michelson–Morley experimental procedure, testing special relativity. The modification is to make one arm of the classical Michelson–Morley (MM) apparatus shorter than the other one. While the Michelson–Morley experiment showed that the speed of light is independent of the ''orientation'' of the apparatus, the Kennedy–Thorndike experiment showed that it is also independent of the ''velocity'' of the apparatus in different inertial frames. It also served as a test to indirectly verify time dilation – while the negative result of the Michelson–Morley experiment can be explained by length contraction alone, the negative result of the Kennedy–Thorndike experiment requires time dilation in addition to length contraction to explain why no Phase (waves), phase shifts will be detected while the Earth moves around the Sun. The first ''direct'' confirma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Michelson–Morley Experiment
The Michelson–Morley experiment was an attempt to measure the motion of the Earth relative to the luminiferous aether, a supposed medium permeating space that was thought to be the carrier of light waves. The experiment was performed between April and July 1887 by American physicists Albert A. Michelson and Edward W. Morley at what is now Case Western Reserve University in Cleveland, Ohio, and published in November of the same year. The experiment compared the speed of light in perpendicular directions in an attempt to detect the relative motion of matter, including their laboratory, through the luminiferous aether, or "aether wind" as it was sometimes called. The result was negative, in that Michelson and Morley found no significant difference between the speed of light in the direction of movement through the presumed aether, and the speed at right angles. This result is generally considered to be the first strong evidence against some aether theories, as well as initiating ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Henri Poincaré
Jules Henri Poincaré (, ; ; 29 April 185417 July 1912) was a French mathematician, Theoretical physics, theoretical physicist, engineer, and philosophy of science, philosopher of science. He is often described as a polymath, and in mathematics as "The Last Universalist", since he excelled in all fields of the discipline as it existed during his lifetime. He has further been called "the Carl Friedrich Gauss, Gauss of History of mathematics, modern mathematics". Due to his success in science, along with his influence and philosophy, he has been called "the philosopher par excellence of modern science". As a mathematician and physicist, he made many original fundamental contributions to Pure mathematics, pure and applied mathematics, mathematical physics, and celestial mechanics. In his research on the three-body problem, Poincaré became the first person to discover a chaotic deterministic system which laid the foundations of modern chaos theory. Poincaré is regarded as the cr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
