Terms: relativity
Matches: 46
Displayed: 30
When you have more than 50 Matches, go to Categories to see the rest.
Categories
Specific Results
- Relativity (Time)
Provides audio of Einstein explaining that energy equals mass times the velocity of light squared. 1-00
- Relativity Tested (CNNfyi.com - Berger)
Describes a test to be made in space to see if one of Einstein's theories about time and motion are accurate.
- Relativity - Einstein's General Theory of Relativity (Humboldt)
Provides a description of Einstein's general theory of relativity. Written in layman's language, but assumes a good understanding of physics. 6-02
- Relativity - Proofs of Einstein's General Theory of Relativity (WhyFiles)
Describes the proofs concluded so far for Einstein's general theory of relativity. Written for students. 6-02
- Relativity - Einstein's General Theory of Relativity (Lycos)
Provides a description of Einstein's general theory of relativity. 6-02
- Relativity
- General Relativity (Wikipedia.org)
"General relativity (GR) or General relativity theory (GRT) is the theory of gravitation published by Albert Einstein in 1915." 10-04
- Special Relativity (Wikipedia.org)
"The Special relativity (SR) or Special theory of relativity is the physical theory published in 1905 by Albert Einstein. It replaced Newtonian notions of space and time, and incorporated electromagnetism as represented by Maxwell's equations. The theory is called "special" because it is a "special" case of Einstein's principle of relativity where the effects of gravity can be ignored." 10-04
- Combining Relativity and Quantum Theory (Physics.Weber.edu)
"The two major physics discoveries of the first part of this century, quantum mechanics and Einstein's theory of special relativity present new challenges when treated together. The energy "uncertainty" introduced in quantum theory combines with the mass-energy equivalence of special relativity to allow the creation of particle/anti-particle pairs by quantum fluctuations when the theories are merged. As a result there is no self-consistent theory which generalizes the simple, one-particle Schrödinger equation into a relativistic quantum wave equation."
"The most successful approach to this problem, developed in the early 30's, begins not with a single relativistic particle, but with a relativistic classical field theory, such as Maxwell's theory of electromagnetism. This classical field theory is then "quantized" in the usual way and the resulting quantum field theory realizes a consistent combination of quantum mechanics and relativity. However, this theory is inherently a many-body theory with the quanta of the normal modes of the classical field having all the properties of physical particles." 01-06
- Noether, Emmy (Gammel)
Provides a very brief biography of the woman who "mathematically proved two of the propositions that formed a cornerstone for the theory of general relativity." 6-00
- Noether, Emmy (Association for Women in Mathematics)
Provides a very brief biography of the woman who "mathematically proved two of the propositions that formed a cornerstone for the theory of general relativity." 6-00
- Gravity Shielding Experiments Explained (PopularMechanics.com - Wilson)
"Isaac Newton, the first physicist, described gravity as an attraction between two masses (see illustration at top of page). Albert Einstein's general theory of relativity suggests mass actually causes space-time to warp around it. Imagine, for instance, the indentation created by placing a bowling ball on a soft bed.
Both theories explain why apples fall from trees. Scientists consider Einstein's theory superior because it explains also why light–which has no mass–appears to bend in strong gravitational fields."
"Most physicists believe that when NASA flips the switch on its gravity modification experiment, absolutely nothing will happen. Then again, it could start the countdown to a bold new era in space exploration." Editor's Note - The article is dated December, 1997. In August, 2002, Boeing Aircraft announced that it is building an anti-gravity device for NASA. 8-02
- Superstrings - String Theory (FirstScience.com)
"Remarkably, all known physical phenomenon can, in principle, be described by these two great theories, relativity and the quantum theory."
"Although these two great theories represent the two pillars upon which ALL physical knowledge is based, the fundamental mystery is why these two theories are so different in almost every way."
"Superstring theory combines relativity and quantum in an elegant, intuitive way. First, it describes the myriad of quantum particles of nature because each particle represents a "note" on a vibrating string. Think of a violin string. No one says that A or B is more fundamental than C. What is fundamental is the string itself."
"Superstring theory says that, if we had a supermicroscope and could peer at an electron, we would see a string vibrating in a certain mode. The string is extremely small (10 to the minus 33 centimeters!) so that the electron looks like a point particle to us." 10-03
- Witten, Edward - Profile (BBC News)
Known for his contributions to the "Theory of Everything" which ties quantum mechanics, the world of the very small to relativity, the world of the very large. His contributions to superstring theory is particularly noted. He has achieved "the highest honour that a mathematician can receive, namely a Fields Medal." 11-03
- Dark Matter (Space.com - Weinstock)
"Eighty-four years after Albert Einstein introduced the world to his theory of general relativity, scientists are seeing that he was right all along about measuring what we now call dark matter."
"Astronomers supported by the National Science Foundation have found the first evidence of an effect called cosmological shear, a phenomenon predicted by Einstein’s theory, in which light from distant cosmic objects bends due to gravitational forces. What’s more, the detection of cosmological shear has allowed astronomers to track down significant amounts of dark matter, non-luminous matter whose presence in the universe has been predicted, but scantly detected until now." 12-03
- AntiMatter (Lawrence Berkeley National Laboratory - Nuclear Science Division)
"In 1930, Paul Dirac developed the first description of the electron that was consistent with both quantum mechanics and special relativity. One of the remarkable predictions of this theory was that an anti-particle of the electron should exist." 7-04
- Superstring Theory (Wikipedia.org)
"Superstring theory is an attempt to explain all of the particles and fundamental forces of nature in one theory by modeling them as vibrations of tiny supersymmetric strings."
"At present, the deepest problem in theoretical physics is harmonizing the theory of general relativity, which describes gravitation and applies to large-scale structures (stars, planets, galaxies), with quantum mechanics which describes the other three fundamental forces acting on the microscopic scale." 10-04
- Space-Time (Wikipedia.org)
"In special relativity and general relativity, time and three-dimensional space are treated together as a single four-dimensional manifold called spacetime (alternatively, space-time)." 10-04
- Editorial - One Country, Two Moralities (AlterNet.org - Cooperman)
Provides a progressive view of the divisions in the nation revealed by voting preferences for the president."
"There are indeed sides, but the dividing line is not morality. It is the ability to tolerate uncertainty, complexity, ambiguity, unknowability, relativity."
"And this tolerance is less a matter of brainpower than of temperament."
"The asymmetry occasionally perturbs me, because I can appreciate their tastes far more readily than they can appreciate mine. But I would wager that our differences have even more to do with genes than they do with upbringing or education. Desire for novelty and risk aversion are both hardwired."
"So I must abandon the solace of thinking my political opponents benighted, uneducated and cognitively impaired."
"But I refuse to think them more moral."
"There are as many moral values at stake in opposing the slaughter of innocent Iraqi children as there are in opposing the abortion of innocent unborn children. As much moral sensitivity in defending the world's wilderness from exploitation as in defending our ... er ... homeland security. And as much moral courage in supporting the rights of people of all sexual orientations as in supporting traditional marriage."
"How does one participate in a democracy in which more than half the people want righteous certainty at any cost – and a significant minority despises this certainty as ignorance, bigotry and cruelty?" 10-04
- -12-11-05 Graphite Reveals Quantum Effects (Scientific American)
"Geim's team found that they [graphenes] do not slow down, even at very low temperatures. In essence, the electrons act as if they have no mass, or no 'rest mass,' to use the more precise phrase from special relativity. It also means that graphite--at least the two-dimensional variety--never stops conducting. Dubbing these pseudo-relativistic particles 'massless Dirac fermions,' the researchers also proved that they travel far faster than electrons in other semiconductors." 12-05
- Quantum Mechanics (Wikipedia.org)
"Quantum mechanics is a fundamental physical theory that replaces Newtonian mechanics and classical electromagnetism at the atomic and subatomic levels and is the underlying framework of many fields of physics and chemistry, including condensed matter physics, quantum chemistry, and particle physics. Along with general relativity, it is one of the pillars of modern physics." 01-06
- The Standard Model (Wikipedia.org)
"The Standard Model of particle physics is a theory which describes the strong, weak, and electromagnetic fundamental forces, as well as the fundamental particles that make up all matter. Developed between 1970 and 1973, it is a quantum field theory, and consistent with both quantum mechanics and special relativity. To date, almost all experimental tests of the three forces described by the Standard Model have agreed with its predictions. However, the Standard Model is not a complete theory of fundamental interactions, primarily because it does not describe the gravitational force." 01-06
- Quantum Field Theory (Theory.Caltech.edu)
"The framework in which quantum mechanics and special relativity are successfully reconciled is called quantum field theory. It is based on three basic principles: two of them, of course, are quantum mechanics and special relativity. The third one, which I wish to emphasize, is the postulate that elementary particles are point-like objects of zero intrinsic size. In practice, they are smeared over a region of space due to quantum effects, but their descripton in the basic equations is as mathematical points." 01-06
- Loop Quantum Gravity (Wikipedia.org)
"Loop quantum gravity (LQG) is a proposed theory of spacetime which is built from the ground up with the idea of spacetime quantization via the mathematically rigorous theory of loop quantization. It preserves many of the important features of general relativity, such as local Lorentz invariance, while at the same time employing quantization of both space and time at the Planck scale in the tradition of quantum mechanics."
"This is not the most popular theory of quantum gravity; many physicists have philosophical problems with it. For one thing, the critics of this theory say that LQG is one theory of gravity and nothing more. There are many other theories of quantum gravity, and a list of them can be found on the Quantum gravity page." 01-06
- Planck Scale (Wikipedia.org)
"The Planck units are often semi-humorously referred to by physicists as 'God's units'. They eliminate anthropocentric arbitrariness from the system of units: some physicists believe that an extra-terrestrial intelligence might be expected to use the same system."
"At the 'Planck scales' in length, time, density, or temperature, one must consider both the effects of quantum mechanics and general relativity. Unfortunately this requires a theory of quantum gravity which does not yet exist."
"Most of the Planck units are either too small or too large for practical use, unless prefixed with large powers of ten." 01-06
- Quantum Gravity (Stanford Encyclopedia of Philosophy)
"Quantum Gravity: A physical theory describing the gravitational interactions of matter and energy in which matter and energy are described by quantum theory. In most, but not all, theories of quantum gravity, gravity is also quantized. Since the contemporary theory of gravity, general relativity, describes gravitation as the curvature of spacetime by matter and energy, a quantization of gravity implies some sort of quantization of spacetime itself. Insofar as all extant physical theories rely on a classical spacetime background, this presents profound methodological and ontological challenges for the philosopher and the physicist." 01-06
- Quantum Gravity (Wikipedia.org)
"Quantum gravity is the field of theoretical physics attempting to unify the theory of quantum mechanics, which describes three of the fundamental forces of nature, with general relativity, the theory of the fourth fundamental force: gravity. The ultimate goal of some is a unified framework for all fundamental forces—a theory of everything." 01-06
- Big Bang Theory (Wikipedia.org)
"In physical cosmology, the Big Bang is the scientific theory that the universe emerged from an enormously dense and hot state about 13.7 billion years ago. The Big Bang theory is based on the observed Hubble's law redshift of distant galaxies that when taken together with the cosmological principle indicate that space is expanding according to the Friedmann-Lemaître model of general relativity. Extrapolated into the past, these observations show that the universe has expanded from a state in which all the matter and energy in the universe was at an immense temperature and density." 04-06
- Antimatter (IBL.gov)
"n 1930, Paul Dirac developed the first description of the electron that was consistent with both quantum mechanics and special relativity. One of the remarkable predictions of this theory was that an anti-particle of the electron should exist. This antielectron would be expected to have the same mass as the electron, but opposite electric charge and magnetic moment. In 1932, Carl Anderson, was examining tracks produced by cosmic rays in a cloud chamber. One particle made a track like an electron, but the curvature of its path in the magnetic field showed that it was positively charged. He named this positive electron a positron. We know that the particle Anderson detected was the anti-electron predicted by Dirac. In the 1950's, physicists at the Lawrence Radiation Laboratory used the Bevatron accelerator to produce the anti-proton, that is a particle with the same mass and spin as the proton, but with negative charge and opposite magnetic moment to that of the proton. In order to create the anti-proton, protons were accelerated to very high energy and then smashed into a target containing other protons. Occasionally, the energy brought into the collision would produce a proton-antiproton pair in addition to the original two protons. This result gave credibility to the idea that for every particle there is a corresponding antiparticle." 06-07
- Large Hadron Collider (LHC) Completed (Time.com)
"Scientists believe the LHC's results will help fill in gaps in the Standard Model, the far-reaching set of equations on the interaction of subatomic particles that is the closest that modern physics comes to a testable 'theory of everything.' For example, scientists believe the LHC will produce a particle, the Higgs Boson, that will end debate over how matter in the universe acquires mass. Or, it could even provide evidence for more ambitious theories of the universe, such as string theory, which unites quantum mechanics and general relativity, the previously known laws of the small and large that are currently incompatible in the Standard Model." 09-08
Back to Top
Send comments to
[Dr. Jerry Adams at jadams@awesomelibrary.org.]
|