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Theory of relativity

Index Theory of relativity

The theory of relativity usually encompasses two interrelated theories by Albert Einstein: special relativity and general relativity. [1]

95 relations: Acceleration, Ad hoc hypothesis, Albert A. Michelson, Albert Einstein, Alfred Bucherer, Astronomy, Astrophysics, Atomic Age, Atomic physics, Binary pulsar, Black hole, Classical mechanics, Clock, Cosmic microwave background, Cosmology, Curvature, Doubly special relativity, Edward W. Morley, Einstein field equations, Electromagnetism, Elementary particle, Encyclopædia Britannica, Equivalence principle, Expansion of the universe, Experimental testing of time dilation, Falsifiability, Force, Frame-dragging, Free fall, Galilean invariance, Galilean transformation, Galileo (satellite navigation), General relativity, Global Positioning System, GLONASS, Gravitational lens, Gravitational redshift, Gravitational time dilation, Gravitational wave, Gravity, Hendrik Lorentz, Henri Poincaré, Hermann Minkowski, History of special relativity, Inertia, Inertial frame of reference, Isaac Newton, Isotropy, Ives–Stilwell experiment, Kennedy–Thorndike experiment, ..., Kinematics, Length contraction, Light, Lorentz factor, Lorentz transformation, Luminiferous aether, Mass in special relativity, Mass–energy equivalence, Max Planck, Maxwell's equations, Mercury (planet), Metric tensor (general relativity), Michelson interferometer, Michelson–Morley experiment, Modern searches for Lorentz violation, Neutron star, Nuclear physics, Phenomenon, Physical cosmology, Physics, Physics Today, Precession, Principle of relativity, Pulsar, Quantum mechanics, Quasar, Redshift, Relativistic Doppler effect, Relativity of simultaneity, Scale relativity, Sidney Perkowitz, Space, Spacetime, Special relativity, Speed of light, Sun, Tensor field, Tests of relativistic energy and momentum, The Times, Theoretical physics, Time dilation, Time in physics, Topology, University of California, Riverside, Vacuum. Expand index (45 more) »


In physics, acceleration is the rate of change of velocity of an object with respect to time.

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Ad hoc hypothesis

In science and philosophy, an ad hoc hypothesis is a hypothesis added to a theory in order to save it from being falsified.

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Albert A. Michelson

Albert Abraham Michelson FFRS HFRSE (December 19, 1852 – May 9, 1931) was an American physicist known for his work on measuring the speed of light and especially for the Michelson–Morley experiment.

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Albert Einstein

Albert Einstein (14 March 1879 – 18 April 1955) was a German-born theoretical physicist who developed the theory of relativity, one of the two pillars of modern physics (alongside quantum mechanics).

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Alfred Bucherer

Alfred Heinrich Bucherer (* 9 July 1863 in Cologne; † 16 April 1927 in Bonn) was a German physicist, who is known for his experiments on relativistic mass.

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Astronomy (from ἀστρονομία) is a natural science that studies celestial objects and phenomena.

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Astrophysics is the branch of astronomy that employs the principles of physics and chemistry "to ascertain the nature of the astronomical objects, rather than their positions or motions in space".

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Atomic Age

The Atomic Age, also known as the Atomic Era, is the period of history following the detonation of the first nuclear ("atomic") bomb, Trinity, on July 16, 1945, during World War II.

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Atomic physics

Atomic physics is the field of physics that studies atoms as an isolated system of electrons and an atomic nucleus.

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Binary pulsar

A binary pulsar is a pulsar with a binary companion, often a white dwarf or neutron star.

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Black hole

A black hole is a region of spacetime exhibiting such strong gravitational effects that nothing—not even particles and electromagnetic radiation such as light—can escape from inside it.

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Classical mechanics

Classical mechanics describes the motion of macroscopic objects, from projectiles to parts of machinery, and astronomical objects, such as spacecraft, planets, stars and galaxies.

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A clock is an instrument to measure, keep, and indicate time.

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Cosmic microwave background

The cosmic microwave background (CMB, CMBR) is electromagnetic radiation as a remnant from an early stage of the universe in Big Bang cosmology.

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Cosmology (from the Greek κόσμος, kosmos "world" and -λογία, -logia "study of") is the study of the origin, evolution, and eventual fate of the universe.

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In mathematics, curvature is any of a number of loosely related concepts in different areas of geometry.

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Doubly special relativity

Doubly special relativity (DSR) – also called deformed special relativity or, by some, extra-special relativity – is a modified theory of special relativity in which there is not only an observer-independent maximum velocity (the speed of light), but an observer-independent maximum energy scale and minimum length scale (the Planck energy and Planck length).

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Edward W. Morley

Edward Williams Morley (January 29, 1838 – February 24, 1923) was an American scientist famous for his extremely precise and accurate measurement of the atomic weight of oxygen, and for the Michelson–Morley experiment.

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Einstein field equations

The Einstein field equations (EFE; also known as Einstein's equations) comprise the set of 10 equations in Albert Einstein's general theory of relativity that describe the fundamental interaction of gravitation as a result of spacetime being curved by mass and energy.

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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.

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Elementary particle

In particle physics, an elementary particle or fundamental particle is a particle with no substructure, thus not composed of other particles.

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Encyclopædia Britannica

The Encyclopædia Britannica (Latin for "British Encyclopaedia"), published by Encyclopædia Britannica, Inc., is a general knowledge English-language encyclopaedia.

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Equivalence principle

In the theory of general relativity, the equivalence principle is any of several related concepts dealing with the equivalence of gravitational and inertial mass, and to Albert Einstein's observation that the gravitational "force" as experienced locally while standing on a massive body (such as the Earth) is the same as the pseudo-force experienced by an observer in a non-inertial (accelerated) frame of reference.

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Expansion of the universe

The expansion of the universe is the increase of the distance between two distant parts of the universe with time.

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Experimental testing of time dilation

Time dilation as predicted by special relativity is often verified by means of particle lifetime experiments.

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A statement, hypothesis, or theory has falsifiability (or is falsifiable) if it can logically be proven false by contradicting it with a basic statement.

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In physics, a force is any interaction that, when unopposed, will change the motion of an object.

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Frame-dragging is an effect on spacetime, predicted by Einstein's general theory of relativity, that is due to non-static stationary distributions of mass–energy.

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Free fall

In Newtonian physics, free fall is any motion of a body where gravity is the only force acting upon it.

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Galilean invariance

Galilean invariance or Galilean relativity states that the laws of motion are the same in all inertial frames.

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Galilean transformation

In physics, a Galilean transformation is used to transform between the coordinates of two reference frames which differ only by constant relative motion within the constructs of Newtonian physics.

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Galileo (satellite navigation)

Galileo is the global navigation satellite system (GNSS) that is being created by the European Union (EU) through the European Space Agency (ESA), headquartered in Prague in the Czech Republic, with two ground operations centres, Oberpfaffenhofen near Munich in Germany and Fucino in Italy.

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General relativity

General relativity (GR, also known as the general theory of relativity or GTR) is the geometric theory of gravitation published by Albert Einstein in 1915 and the current description of gravitation in modern physics.

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Global Positioning System

The Global Positioning System (GPS), originally Navstar GPS, is a satellite-based radionavigation system owned by the United States government and operated by the United States Air Force.

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GLONASS (ГЛОНАСС,; Глобальная навигационная спутниковая система; transliteration), or "Global Navigation Satellite System", is a space-based satellite navigation system operating in the radionavigation-satellite service.

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Gravitational lens

A gravitational lens is a distribution of matter (such as a cluster of galaxies) between a distant light source and an observer, that is capable of bending the light from the source as the light travels towards the observer.

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Gravitational redshift

In astrophysics, gravitational redshift or Einstein shift is the process by which electromagnetic radiation originating from a source that is in a gravitational field is reduced in frequency, or redshifted, when observed in a region at a higher gravitational potential.

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Gravitational time dilation

Gravitational time dilation is a form of time dilation, an actual difference of elapsed time between two events as measured by observers situated at varying distances from a gravitating mass.

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Gravitational wave

Gravitational waves are the disturbance in the fabric ("curvature") of spacetime generated by accelerated masses and propagate as waves outward from their source at the speed of light.

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Gravity, or gravitation, is a natural phenomenon by which all things with mass or energy—including planets, stars, galaxies, and even light—are brought toward (or gravitate toward) one another.

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Hendrik Lorentz

Hendrik Antoon Lorentz (18 July 1853 – 4 February 1928) was a Dutch physicist who shared the 1902 Nobel Prize in Physics with Pieter Zeeman for the discovery and theoretical explanation of the Zeeman effect.

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Henri Poincaré

Jules Henri Poincaré (29 April 1854 – 17 July 1912) was a French mathematician, theoretical physicist, engineer, and philosopher of science.

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Hermann Minkowski

Hermann Minkowski (22 June 1864 – 12 January 1909) was a German mathematician and professor at Königsberg, Zürich and Göttingen.

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History of special relativity

The history of special relativity consists of many theoretical results and empirical findings obtained by Albert A. Michelson, Hendrik Lorentz, Henri Poincaré and others.

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Inertia is the resistance of any physical object to any change in its position and state of motion.

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Inertial frame of reference

An inertial frame of reference in classical physics and special relativity is a frame of reference in which a body with zero net force acting upon it is not accelerating; that is, such a body is at rest or it is moving at a constant speed in a straight line.

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Isaac Newton

Sir Isaac Newton (25 December 1642 – 20 March 1726/27) was an English mathematician, astronomer, theologian, author and physicist (described in his own day as a "natural philosopher") who is widely recognised as one of the most influential scientists of all time, and a key figure in the scientific revolution.

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Isotropy is uniformity in all orientations; it is derived from the Greek isos (ἴσος, "equal") and tropos (τρόπος, "way").

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Ives–Stilwell experiment

The Ives–Stilwell experiment tested the contribution of relativistic time dilation to the Doppler shift of light.

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Kennedy–Thorndike experiment

The Kennedy–Thorndike experiment, first conducted in 1932, is a modified form of the Michelson–Morley experimental procedure, testing special relativity.

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Kinematics is a branch of classical mechanics that describes the motion of points, bodies (objects), and systems of bodies (groups of objects) without considering the mass of each or the forces that caused the motion.

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Length contraction

Length contraction is the phenomenon that a moving object's length is measured to be shorter than its proper length, which is the length as measured in the object's own rest frame.

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Light is electromagnetic radiation within a certain portion of the electromagnetic spectrum.

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Lorentz factor

The Lorentz factor or Lorentz term is the factor by which time, length, and relativistic mass change for an object while that object is moving.

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Lorentz transformation

In physics, the Lorentz transformations (or transformation) are coordinate transformations between two coordinate frames that move at constant velocity relative to each other.

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Luminiferous aether

In the late 19th century, luminiferous aether or ether ("luminiferous", meaning "light-bearing"), was the postulated medium for the propagation of light.

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Mass in special relativity

Mass in special relativity incorporates the general understandings from the laws of motion of special relativity along with its concept of mass–energy equivalence.

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Mass–energy equivalence

In physics, mass–energy equivalence states that anything having mass has an equivalent amount of energy and vice versa, with these fundamental quantities directly relating to one another by Albert Einstein's famous formula: E.

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Max Planck

Max Karl Ernst Ludwig Planck, FRS (23 April 1858 – 4 October 1947) was a German theoretical physicist whose discovery of energy quanta won him the Nobel Prize in Physics in 1918.

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Maxwell's equations

Maxwell's equations are a set of partial differential equations that, together with the Lorentz force law, form the foundation of classical electromagnetism, classical optics, and electric circuits.

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Mercury (planet)

Mercury is the smallest and innermost planet in the Solar System.

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Metric tensor (general relativity)

In general relativity, the metric tensor (in this context often abbreviated to simply the metric) is the fundamental object of study.

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Michelson interferometer

The Michelson interferometer is a common configuration for optical interferometry and was invented by Albert Abraham Michelson.

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Michelson–Morley experiment

The Michelson–Morley experiment was performed between April and July, 1887 by 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.

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Modern searches for Lorentz violation

Modern searches for Lorentz violation are scientific studies that look for deviations from Lorentz invariance or symmetry, a set of fundamental frameworks that underpin modern science and fundamental physics in particular.

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Neutron star

A neutron star is the collapsed core of a large star which before collapse had a total of between 10 and 29 solar masses.

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Nuclear physics

Nuclear physics is the field of physics that studies atomic nuclei and their constituents and interactions.

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A phenomenon (Greek: φαινόμενον, phainómenon, from the verb phainein, to show, shine, appear, to be manifest or manifest itself, plural phenomena) is any thing which manifests itself.

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Physical cosmology

Physical cosmology is the study of the largest-scale structures and dynamics of the Universe and is concerned with fundamental questions about its origin, structure, evolution, and ultimate fate.

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Physics (from knowledge of nature, from φύσις phýsis "nature") is the natural science that studies matterAt the start of The Feynman Lectures on Physics, Richard Feynman offers the atomic hypothesis as the single most prolific scientific concept: "If, in some cataclysm, all scientific knowledge were to be destroyed one sentence what statement would contain the most information in the fewest words? I believe it is that all things are made up of atoms – little particles that move around in perpetual motion, attracting each other when they are a little distance apart, but repelling upon being squeezed into one another..." and its motion and behavior through space and time and that studies the related entities of energy and force."Physical science is that department of knowledge which relates to the order of nature, or, in other words, to the regular succession of events." Physics is one of the most fundamental scientific disciplines, and its main goal is to understand how the universe behaves."Physics is one of the most fundamental of the sciences. Scientists of all disciplines use the ideas of physics, including chemists who study the structure of molecules, paleontologists who try to reconstruct how dinosaurs walked, and climatologists who study how human activities affect the atmosphere and oceans. Physics is also the foundation of all engineering and technology. No engineer could design a flat-screen TV, an interplanetary spacecraft, or even a better mousetrap without first understanding the basic laws of physics. (...) You will come to see physics as a towering achievement of the human intellect in its quest to understand our world and ourselves."Physics is an experimental science. Physicists observe the phenomena of nature and try to find patterns that relate these phenomena.""Physics is the study of your world and the world and universe around you." Physics is one of the oldest academic disciplines and, through its inclusion of astronomy, perhaps the oldest. Over the last two millennia, physics, chemistry, biology, and certain branches of mathematics were a part of natural philosophy, but during the scientific revolution in the 17th century, these natural sciences emerged as unique research endeavors in their own right. Physics intersects with many interdisciplinary areas of research, such as biophysics and quantum chemistry, and the boundaries of physics are not rigidly defined. New ideas in physics often explain the fundamental mechanisms studied by other sciences and suggest new avenues of research in academic disciplines such as mathematics and philosophy. Advances in physics often enable advances in new technologies. For example, advances in the understanding of electromagnetism and nuclear physics led directly to the development of new products that have dramatically transformed modern-day society, such as television, computers, domestic appliances, and nuclear weapons; advances in thermodynamics led to the development of industrialization; and advances in mechanics inspired the development of calculus.

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Physics Today

Physics Today is the membership magazine of the American Institute of Physics that was established in 1948.

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Precession is a change in the orientation of the rotational axis of a rotating body.

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Principle of relativity

In physics, the principle of relativity is the requirement that the equations describing the laws of physics have the same form in all admissible frames of reference.

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A pulsar (from pulse and -ar as in quasar) is a highly magnetized rotating neutron star or white dwarf that emits a beam of electromagnetic radiation.

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Quantum mechanics

Quantum mechanics (QM; also known as quantum physics, quantum theory, the wave mechanical model, or matrix mechanics), including quantum field theory, is a fundamental theory in physics which describes nature at the smallest scales of energy levels of atoms and subatomic particles.

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A quasar (also known as a QSO or quasi-stellar object) is an extremely luminous active galactic nucleus (AGN).

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In physics, redshift happens when light or other electromagnetic radiation from an object is increased in wavelength, or shifted to the red end of the spectrum.

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Relativistic Doppler effect

The relativistic Doppler effect is the change in frequency (and wavelength) of light, caused by the relative motion of the source and the observer (as in the classical Doppler effect), when taking into account effects described by the special theory of relativity.

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Relativity of simultaneity

In physics, the relativity of simultaneity is the concept that distant simultaneity – whether two spatially separated events occur at the same time – is not absolute, but depends on the observer's reference frame.

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Scale relativity

Scale relativity is a geometrical and fractal space-time physical theory.

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Sidney Perkowitz

Sidney Perkowitz is a scientist and science writer.

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Space is the boundless three-dimensional extent in which objects and events have relative position and direction.

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In physics, spacetime is any mathematical model that fuses the three dimensions of space and the one dimension of time into a single four-dimensional continuum.

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Special relativity

In physics, special relativity (SR, also known as the special theory of relativity or STR) is the generally accepted and experimentally well-confirmed physical theory regarding the relationship between space and time.

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Speed of light

The speed of light in vacuum, commonly denoted, is a universal physical constant important in many areas of physics.

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The Sun is the star at the center of the Solar System.

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Tensor field

In mathematics and physics, a tensor field assigns a tensor to each point of a mathematical space (typically a Euclidean space or manifold).

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Tests of relativistic energy and momentum

Tests of relativistic energy and momentum are aimed at measuring the relativistic expressions for energy, momentum, and mass.

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The Times

The Times is a British daily (Monday to Saturday) national newspaper based in London, England.

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Theoretical physics

Theoretical physics is a branch of physics that employs mathematical models and abstractions of physical objects and systems to rationalize, explain and predict natural phenomena.

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Time dilation

According to the theory of relativity, time dilation is a difference in the elapsed time measured by two observers, either due to a velocity difference relative to each other, or by being differently situated relative to a gravitational field.

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Time in physics

Time in physics is defined by its measurement: time is what a clock reads.

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In mathematics, topology (from the Greek τόπος, place, and λόγος, study) is concerned with the properties of space that are preserved under continuous deformations, such as stretching, crumpling and bending, but not tearing or gluing.

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University of California, Riverside

The University of California, Riverside (UCR or UC Riverside), is a public research university and one of the 10 general campuses of the University of California system.

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Vacuum is space devoid of matter.

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[1] https://en.wikipedia.org/wiki/Theory_of_relativity

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