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Introduction to general relativity

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1501:. Unlike the Cartesian coordinates of the plane, coordinate differences are not the same as distances on the surface, as shown in the diagram on the right: for someone at the equator, moving 30 degrees of longitude westward (magenta line) corresponds to a distance of roughly 3,300 kilometers (2,100 mi), while for someone at a latitude of 55 degrees, moving 30 degrees of longitude westward (blue line) covers a distance of merely 1,900 kilometers (1,200 mi). Coordinates therefore do not provide enough information to describe the geometry of a spherical surface, or indeed the geometry of any more complicated space or spacetime. That information is precisely what is encoded in the metric, which is a function defined at each point of the surface (or space, or spacetime) and relates coordinate differences to differences in distance. All other quantities that are of interest in geometry, such as the length of any given curve, or the angle at which two curves meet, can be computed from this metric function. 5982: 734: 1886:: clocks aboard satellites orbiting the Earth, and reference clocks stationed on the Earth's surface. General relativity predicts that these two sets of clocks should tick at slightly different rates, due to their different motions (an effect already predicted by special relativity) and their different positions within the Earth's gravitational field. In order to ensure the system's accuracy, either the satellite clocks are slowed down by a relativistic factor, or that same factor is made part of the evaluation algorithm. In turn, tests of the system's accuracy (especially the very thorough measurements that are part of the definition of 1863: â€“ an astronomical object that emits a tight beam of radiowaves. These beams strike the Earth at very regular intervals, similarly to the way that the rotating beam of a lighthouse means that an observer sees the lighthouse blink, and can be observed as a highly regular series of pulses. General relativity predicts specific deviations from the regularity of these radio pulses. For instance, at times when the radio waves pass close to the other neutron star, they should be deflected by the star's gravitational field. The observed pulse patterns are impressively close to those predicted by general relativity. 2163:: over time, black holes retain only a minimal set of distinguishing features (these theorems have become known as "no-hair" theorems), regardless of the starting geometric shape. For instance, in the long term, the collapse of a hypothetical matter cube will not result in a cube-shaped black hole. Instead, the resulting black hole will be indistinguishable from a black hole formed by the collapse of a spherical mass. In its transition to a spherical shape, the black hole formed by the collapse of a more complicated shape will emit gravitational waves. 1368:, the straightest possible lines in spacetime. But still there are crucial differences between them and the truly straight lines that can be traced out in the gravity-free spacetime of special relativity. In special relativity, parallel geodesics remain parallel. In a gravitational field with tidal effects, this will not, in general, be the case. If, for example, two bodies are initially at rest relative to each other, but are then dropped in the Earth's gravitational field, they will move towards each other as they fall towards the Earth's center. 1026:
Einstein's master insight was that the constant, familiar pull of the Earth's gravitational field is fundamentally the same as these fictitious forces. The apparent magnitude of the fictitious forces always appears to be proportional to the mass of any object on which they act – for instance, the driver's seat exerts just enough force to accelerate the driver at the same rate as the car. By analogy, Einstein proposed that an object in a gravitational field should feel a gravitational force proportional to its mass, as embodied in
5994: 64: 2172: 1691: 1043: 6066: 1715:. Einstein's theory predicts a more complicated curve: the planet behaves as if it were travelling around an ellipse, but at the same time, the ellipse as a whole is rotating slowly around the star. In the diagram on the right, the ellipse predicted by Newtonian gravity is shown in red, and part of the orbit predicted by Einstein in blue. For a planet orbiting the Sun, this deviation from Newton's orbits is known as the 5830: 958:; objects either float motionless or drift at constant speed. Since everything in the elevator is falling together, no gravitational effect can be observed. In this way, the experiences of an observer in free fall are indistinguishable from those of an observer in deep space, far from any significant source of gravity. Such observers are the privileged ("inertial") observers Einstein described in his theory of 747: 983: 27: 4919: 1086:
ages by that amount; each clock, in short, is in perfect agreement with all processes happening in its immediate vicinity. It is only when the clocks are compared between separate observers that one can notice that time runs more slowly for the lower observer than for the higher. This effect is minute, but it too has been confirmed experimentally in multiple experiments, as described
6030: 1922: 6054: 1071:, that is, shifted towards higher frequencies. Einstein argued that such frequency shifts must also be observed in a gravitational field. This is illustrated in the figure at left, which shows a light wave that is gradually red-shifted as it works its way upwards against the gravitational acceleration. This effect has been confirmed experimentally, as described 6006: 6042: 1976:, which does not give off light and can be observed only by its gravitational effects. One particularly interesting application are large-scale observations, where the lensing masses are spread out over a significant fraction of the observable universe, and can be used to obtain information about the large-scale properties and evolution of our cosmos. 6018: 2082: 1406:, curvature at every point in spacetime is also caused by whatever matter is present. Here, too, mass is a key property in determining the gravitational influence of matter. But in a relativistic theory of gravity, mass cannot be the only source of gravity. Relativity links mass with energy, and energy with momentum. 1423:, is the most famous consequence of special relativity. In relativity, mass and energy are two different ways of describing one physical quantity. If a physical system has energy, it also has the corresponding mass, and vice versa. In particular, all properties of a body that are associated with energy, such as its 2246:
itself acts as a source of attractive (or, less commonly, repulsive) gravity. Einstein originally introduced this term in his pioneering 1917 paper on cosmology, with a very specific motivation: contemporary cosmological thought held the universe to be static, and the additional term was required for
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as the downwards pull of a gravitational force, but as the upwards push of external forces. These forces deflect all bodies resting on the Earth's surface from the geodesics they would otherwise follow. For objects massive enough that their own gravitational influence cannot be neglected, the laws of
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A more basic manifestation of the same effect involves two bodies that are falling side by side towards the Earth, with a similar position and velocity. In a reference frame that is in free fall alongside these bodies, they appear to hover weightlessly â€“ but not exactly so. These bodies are not
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It is important to stress that, for each observer, there are no observable changes of the flow of time for events or processes that are at rest in his or her reference frame. Five-minute-eggs as timed by each observer's clock have the same consistency; as one year passes on each clock, each observer
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Several physicists, including Einstein, searched for a theory that would reconcile Newton's law of gravity and special relativity. Only Einstein's theory proved to be consistent with experiments and observations. To understand the theory's basic ideas, it is instructive to follow Einstein's thinking
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There are several properties that make black holes the most promising sources of gravitational waves. One reason is that black holes are the most compact objects that can orbit each other as part of a binary system; as a result, the gravitational waves emitted by such a system are especially strong.
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and be deflected slightly so as to reach an observer on Earth, while light passing along the opposite side of that same galaxy is deflected as well, reaching the same observer from a slightly different direction. As a result, that particular observer will see one astronomical object in two different
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By cosmic standards, gravity throughout the solar system is weak. Since the differences between the predictions of Einstein's and Newton's theories are most pronounced when gravity is strong, physicists have long been interested in testing various relativistic effects in a setting with comparatively
1458:. Taken together, in general relativity it is mass, energy, momentum, pressure and tension that serve as sources of gravity: they are how matter tells spacetime how to curve. In the theory's mathematical formulation, all these quantities are but aspects of a more general physical quantity called the 1371:
Compared with planets and other astronomical bodies, the objects of everyday life (people, cars, houses, even mountains) have little mass. Where such objects are concerned, the laws governing the behavior of test particles are sufficient to describe what happens. Notably, in order to deflect a test
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The properties of geodesics differ from those of straight lines. For example, on a plane, parallel lines never meet, but this is not so for geodesics on the surface of the Earth: for example, lines of longitude are parallel at the equator, but intersect at the poles. Analogously, the world lines of
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to account for the acceleration experienced by the observer and objects around them. In the example of the driver being pressed into their seat, the force felt by the driver is one example; another is the force one can feel while pulling the arms up and out if attempting to spin around like a top.
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had been accepted for more than two hundred years as a valid description of the gravitational force between masses. In Newton's model, gravity is the result of an attractive force between massive objects. Although even Newton was troubled by the unknown nature of that force, the basic framework was
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from its magnetic poles. As the pulsar rotates, its beam sweeps over the Earth, where it is seen as a regular series of radio pulses, just as a ship at sea observes regular flashes of light from the rotating light in a lighthouse. This regular pattern of radio pulses functions as a highly accurate
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as a whole. A key point is that, on large scales, our universe appears to be constructed along very simple lines: all current observations suggest that, on average, the structure of the cosmos should be approximately the same, regardless of an observer's location or direction of observation: the
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of light. Consider two observers aboard an accelerating rocket-ship. Aboard such a ship, there is a natural concept of "up" and "down": the direction in which the ship accelerates is "up", and free-floating objects accelerate in the opposite direction, falling "downward". Assume that one of the
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Einstein explained this in section XX of Einstein 1961. He considered an object "suspended" by a rope from the ceiling of a room aboard an accelerating rocket: from inside the room it looks as if gravitation is pulling the object down with a force proportional to its mass, but from outside the
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with considerable accuracy. As the precision of experimental measurements gradually improved, some discrepancies with Newton's predictions were observed, and these were accounted for in the general theory of relativity. Similarly, the predictions of general relativity must also be checked with
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Beyond the challenges of quantum effects and cosmology, research on general relativity is rich with possibilities for further exploration: mathematical relativists explore the nature of singularities and the fundamental properties of Einstein's equations, and ever more comprehensive computer
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Of these tests, only the perihelion advance of Mercury was known prior to Einstein's final publication of general relativity in 1916. The subsequent experimental confirmation of his other predictions, especially the first measurements of the deflection of light by the sun in 1919, catapulted
1097:: in a gravitational field, light is deflected downward, to the center of the gravitational field. Quantitatively, his results were off by a factor of two; the correct derivation requires a more complete formulation of the theory of general relativity, not just the equivalence principle. 1519:, and the principle that "spacetime tells matter how to move, and matter tells spacetime how to curve" means that these quantities must be related to each other. Einstein formulated this relation by using the Riemann curvature tensor and the metric to define another geometrical quantity 883:
Although general relativity is not the only relativistic theory of gravity, it is the simplest one that is consistent with the experimental data. Nevertheless, a number of open questions remain, the most fundamental of which is how general relativity can be reconciled with the laws of
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The equivalence between inertia and gravity cannot explain tidal effects â€“ it cannot explain variations in the gravitational field. For that, a theory is needed which describes the way that matter (such as the large mass of the Earth) affects the inertial environment around it.
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constructing static model universes within the framework of general relativity. When it became apparent that the universe is not static, but expanding, Einstein was quick to discard this additional term. Since the end of the 1990s, however, astronomical evidence indicating an
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General relativity is very successful in providing a framework for accurate models which describe an impressive array of physical phenomena. On the other hand, there are many interesting open questions, and in particular, the theory as a whole is almost certainly incomplete.
1180:. For gravitational fields, the absence or presence of tidal forces determines whether or not the influence of gravity can be eliminated by choosing a freely falling reference frame. Similarly, the absence or presence of curvature determines whether or not a surface is 2510:
This effect can be derived directly within special relativity, either by looking at the equivalent situation of two observers in an accelerated rocket-ship or by looking at a falling elevator; in both situations, the frequency shift has an equivalent description as a
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In fact, when starting from the complete theory, Einstein's equation can be used to derive these more complicated laws of motion for matter as a consequence of geometry, but deriving from this the motion of idealized test particles is a highly non-trivial task, cf.
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and thus following a geodesic, which they would otherwise be doing without the chair there, or any other matter in between them and the center point of the Earth. In this way, general relativity explains the daily experience of gravity on the surface of the Earth
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In 1907, Einstein was still eight years away from completing the general theory of relativity. Nonetheless, he was able to make a number of novel, testable predictions that were based on his starting point for developing his new theory: the equivalence principle.
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in the 1850s. With the help of Riemannian geometry, Einstein formulated a geometric description of gravity in which Minkowski's spacetime is replaced by distorted, curved spacetime, just as curved surfaces are a generalization of ordinary plane surfaces.
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Einstein hypothesized that the similar experiences of weightless observers and inertial observers in special relativity represented a fundamental property of gravity, and he made this the cornerstone of his theory of general relativity, formalized in his
1082:: Since the "higher" observer measures the same light wave to have a lower frequency than the "lower" observer, time must be passing faster for the higher observer. Thus, time runs more slowly for observers the lower they are in a gravitational field. 1113:
The equivalence between gravitational and inertial effects does not constitute a complete theory of gravity. When it comes to explaining gravity near our own location on the Earth's surface, noting that our reference frame is not in free fall, so that
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are the centerpiece of general relativity. They provide a precise formulation of the relationship between spacetime geometry and the properties of matter, using the language of mathematics. More concretely, they are formulated using the concepts of
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Conversely, any effect observed in an accelerated reference frame should also be observed in a gravitational field of corresponding strength. This principle allowed Einstein to predict several novel effects of gravity in 1907, as explained in the
2419:, chapters 2–4. It is impossible to say whether the problem of Newtonian gravity crossed Einstein's mind before 1907, but, by his own admission, his first serious attempts to reconcile that theory with special relativity date to that year, cf. 2497:, use the equivalence principle, the equivalence of gravity and inertial forces, and the results of special relativity for the propagation of light and for accelerated observers (the latter by considering, at each moment, the instantaneous 1486: 1118:
are to be expected, provides a suitable explanation. But a freely falling reference frame on one side of the Earth cannot explain why the people on the opposite side of the Earth experience a gravitational pull in the opposite direction.
1306: 1106: 1446:. In special relativity, just as space and time are different aspects of a more comprehensive entity called spacetime, energy and momentum are merely different aspects of a unified, four-dimensional quantity that physicists call 2307:
exist within the universe if the laws of general relativity were to hold without any quantum modifications. The best-known examples are the singularities associated with the model universes that describe black holes and the
1750:). In the framework of Newtonian gravity, a heuristic argument can be made that leads to light deflection by half that amount. The different predictions can be tested by observing stars that are close to the Sun during a 2017:
each other and, as they do so, gradually lose energy by emitting gravitational waves. For ordinary stars like the Sun, this energy loss would be too small to be detectable, but this energy loss was observed in 1974 in a
2299:. These singularities are boundaries ("sharp edges") of spacetime at which geometry becomes ill-defined, with the consequence that general relativity itself loses its predictive power. Furthermore, there are so-called 4194: 135: 1590: 3831: 4909: 2295:, there is at present no consistent and complete theory. It has long been hoped that a theory of quantum gravity would also eliminate another problematic feature of general relativity: the presence of 1968:
uses lensing effects as an important tool to infer properties of the lensing object. Even in cases where that object is not directly visible, the shape of a lensed image provides information about the
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Since light is deflected in a gravitational field, it is possible for the light of a distant object to reach an observer along two or more paths. For instance, light of a very distant object such as a
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on Earth, and is far from any source of gravity. The objects are being pulled towards the floor by the same "inertial force" that presses the driver of an accelerating car into the back of their seat.
2065:) which was launched in 2015. Gravitational wave observations can be used to obtain information about compact objects such as neutron stars and black holes, and also to probe the state of the early 1987:, a direct consequence of Einstein's theory, are distortions of geometry that propagate at the speed of light, and can be thought of as ripples in spacetime. They should not be confused with the 2339:
simulations of specific spacetimes (such as those describing merging black holes) are run. More than one hundred years after the theory was first published, research is more active than ever.
5533: 1663: 505: 1450:. In consequence, if energy is a source of gravity, momentum must be a source as well. The same is true for quantities that are directly related to energy and momentum, namely internal 5864: 2050:
in 1993. Since then, several other binary pulsars have been found. The most useful are those in which both stars are pulsars, since they provide accurate tests of general relativity.
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While the equivalence principle is still part of modern expositions of general relativity, there are some differences between the modern version and Einstein's original concept, cf.
2139:, and matter falling onto black holes is thought to be responsible for some of the brightest astronomical phenomena imaginable. Notable examples of great interest to astronomers are 1297:, examine which properties of matter serve as a source for gravity, and, finally, introduce Einstein's equations, which relate these matter properties to the curvature of spacetime. 4924: 1360:. These paths are certainly not straight, simply because they must follow the curvature of the Earth's surface. But they are as straight as is possible subject to this constraint. 5931: 2354: 2327:. There have been several controversial proposals to remove the need for these enigmatic forms of matter and energy, by modifying the laws governing gravity and the dynamics of 1265:
After he had realized the validity of this geometric analogy, it took Einstein a further three years to find the missing cornerstone of his theory: the equations describing how
1159:. An example is the transition from an inertial reference frame (in which free particles coast along straight paths at constant speeds) to a rotating reference frame (in which 821:
Experiments and observations show that Einstein's description of gravitation accounts for several effects that are unexplained by Newton's law, such as minute anomalies in the
778: 4230: 1770:, have confirmed Eddington's results with significantly better precision (the first such measurements date from 1967, the most recent comprehensive analysis from 2004). 1723:, dates back to 1859. The most accurate results for Mercury and for other planets to date are based on measurements which were undertaken between 1966 and 1990, using 1512:, the spacetime in the theory of relativity, is curved at each point. As has already been mentioned, the matter content of the spacetime defines another quantity, the 157: 2100: â€“ a region of space with a gravitational effect so strong that not even light can escape. Certain types of black holes are thought to be the final state in the 1635: 4908: 4977: 860:, regions of space where the gravitational effect is strong enough that even light cannot escape. Their strong gravity is thought to be responsible for the intense 1493:
A spherical surface like that of the Earth provides a simple example. The location of any point on the surface can be described by two coordinates: the geographic
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observers is "higher up" than the other. When the lower observer sends a light signal to the higher observer, the acceleration of the ship causes the light to be
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particle from its geodesic path, an external force must be applied. A chair someone is sitting on applies an external upwards force preventing the person from
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Einstein to international stardom. These three experiments justified adopting general relativity over Newton's theory and, incidentally, over a number of
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rocket it looks as if the rope is simply transferring the acceleration of the rocket to the object, and must therefore exert just the "force" to do so.
2035:"clock". It can be used to time the double star's orbital period, and it reacts sensitively to distortions of spacetime in its immediate neighborhood. 1151:
While Einstein was exploring the equivalence of gravity and acceleration as well as the role of tidal forces, he discovered several analogies with the
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For an overview of the history of black hole physics from its beginnings in the early 20th century to modern times, see the very readable account by
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Springel, Volker; White, Simon D. M.; Jenkins, Adrian; Frenk, Carlos S.; Yoshida, N; Gao, L; Navarro, J; Thacker, R; Croton, D; et al. (2005),
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B. P. Abbott; et al. (LIGO Scientific and Virgo Collaborations) (2016), "Observation of Gravitational Waves from a Binary Black Hole Merger",
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of the universe are obtained by combining these simple solutions to general relativity with theories describing the properties of the universe's
1482:. The metric encodes the information needed to compute the fundamental geometric notions of distance and angle in a curved space (or spacetime). 806:
between 1907 and 1915. The theory of general relativity says that the observed gravitational effect between masses results from their warping of
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Hartl, Gerhard (2005), "The Confirmation of the General Theory of Relativity by the British Eclipse Expedition of 1919", in Renn, JĂŒrgen (ed.),
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in the presence of massive bodies. In particular, starlight is deflected as it passes near the Sun, leading to apparent shifts of up to 1.75
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Objects are falling to the floor because the room is resting on the surface of the Earth and the objects are being pulled down by gravity.
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distribution responsible for the light deflection. In particular, gravitational lensing provides one way to measure the distribution of
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According to general relativity, light does not travel along straight lines when it propagates in a gravitational field. Instead, it is
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are each determined by several functions of the coordinates of spacetime, and the equations equate each of these component functions.
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satellite experiment launched in 2004, with results confirming relativity to within 0.5% and 15%, respectively, as of December 2008.
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Converging geodesics: two lines of longitude (green) that start out in parallel at the equator (red) but converge to meet at the pole
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Kennefick, Daniel (2007), "Not Only Because of Theory: Dyson, Eddington and the Competing Myths of the 1919 Eclipse Expedition",
63: 2462:, p. 64f. Einstein himself also explains this in section XX of his non-technical book Einstein 1961. Following earlier ideas by 1386:
motion are somewhat more complicated than for test particles, although it remains true that spacetime tells matter how to move.
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Kennefick, Daniel (2005), "Astronomers Test General Relativity: Light-bending and the Solar Redshift", in Renn, JĂŒrgen (ed.),
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For a more detailed definition of the metric, but one that is more informal than a textbook presentation, see chapter 14.4 of
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Indirectly, the effect of gravitational waves had been detected in observations of specific binary stars. Such pairs of stars
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The gravitational redshift of a light wave as it moves upwards against a gravitational field (caused by the yellow star below)
5402: 4558: 3294: 2467: 2003: 1832: 1727:. General relativity predicts the correct anomalous perihelion shift for all planets where this can be measured accurately ( 846: 5480: 2704:
A thorough, yet accessible account of basic differential geometry and its application in general relativity can be found in
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and time. Some then-accepted physical theories were inconsistent with that framework; a key example was Newton's theory of
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Objects are falling to the floor because the room is aboard a rocket in space, which is accelerating at 9.81 m/s, the
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Kramer, Michael (2004), "Millisecond Pulsars as Tools of Fundamental Physics", in Karshenboim, S. G.; Peik, E. (eds.),
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The metric function and its rate of change from point to point can be used to define a geometrical quantity called the
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Proceedings of the 16th International Conference on General Relativity and Gravitation, held 15–21 July 2001 in Durban
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expansion consistent with a cosmological constant â€“ or, equivalently, with a particular and ubiquitous kind of
2220:. According to these models, our present universe emerged from an extremely dense high-temperature state â€“ the 5725: 5167: 5120: 4963:. Website featuring articles on a variety of aspects of relativistic physics for a general audience, hosted by the 1898: 1679: 913: 909: 655: 203: 4428: 3859: 455: 5885: 5755: 5381: 5062: 2043: 2031: 1871: 267: 2200:. Such comparatively simple universes can be described by simple solutions of Einstein's equations. The current 1762:. Eddington's results were not very accurate; subsequent observations of the deflection of the light of distant 1758:, confirmed that Einstein's prediction was correct, and the Newtonian predictions wrong, via observation of the 1513: 1459: 1188:. In the summer of 1912, inspired by these analogies, Einstein searched for a geometric formulation of gravity. 530: 5938: 5890: 5780: 5330: 5090: 5001: 1505: 690: 680: 347: 5509: 5431: 1333:, and in curved spacetime straight world lines may not exist. Instead, test particles move along lines called 409: 1131:
on opposite sides of the Earth, the effect is large. Such differences in force are also responsible for the
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A good starting point for a snapshot of present-day research in relativity is the electronic review journal
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In order to map a body's gravitational influence, it is useful to think about what physicists call probe or
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frame of reference. An observer in a closed room cannot tell which of the following two scenarios is true:
475: 5735: 5462: 5136: 5100: 4765: 2128:, and they play a key role in current models of how galaxies have formed over the past billions of years. 2047: 1773: 1608: 1286: 1051: 645: 630: 237: 3127:. A treatment that is more thorough, yet involves only comparatively little mathematics can be found in 1242:; the orbits of bodies moving at constant speed without changing direction correspond to straight lines. 986:
Ball falling to the floor in an accelerating rocket (left) and on Earth (right). The effect is identical.
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have to be introduced in order to explain particle motion): this is analogous to the transition from a
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for the light than the first sent out. Conversely, light sent from the higher observer to the lower is
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Most effects of gravity vanish in free fall, but effects that seem the same as those of gravity can be
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space probe (artist's impression): radio signals sent between the Earth and the probe (green wave) are
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space probe. One set of tests focuses on effects predicted by general relativity for the behavior of
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experiment, and Einstein himself devised three tests now known as the classical tests of the theory:
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One particular set of observations is related to eminently useful practical applications, namely to
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This article is a non-technical introduction to the subject. For the main encyclopedia article, see
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falling in precisely the same direction, but towards a single point in space: namely, the Earth's
920:). Special relativity introduced a new framework for all of physics by proposing new concepts of 495: 6046: 6034: 5998: 5785: 5685: 5467: 5448: 5442: 5393: 5335: 5244: 5162: 5080: 5057: 5025: 4981: 4819: 4680: 4638: 4451: 4348: 4322: 4131: 4111: 4075: 4039: 4023: 3997: 3949: 3791: 3709: 3683: 3637: 3559: 3049: 3015: 2805: 2649: 2623: 2384: 2359: 2349: 2201: 2039: 1984: 1934: 1678:
No scientific theory is self-evidently true; each is a model that must be checked by experiment.
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For elementary presentations of the concept of spacetime, see the first section in chapter 2 of
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An accessible account of relativistic effects in the global positioning system can be found in
1690: 5795: 5665: 5627: 5619: 5220: 5177: 4857: 4794: 4773: 4720: 4699: 4672: 4609: 4564: 4541: 4523: 4505: 4489: 4400: 4377: 4222: 4180: 4155: 4101: 4057: 3979: 3904: 3882: 3845: 3814: 3783: 3743: 3725: 3476: 3453: 3448:(2005), "The Cassini Experiment: Investigating the Nature of Gravity", in Renn, JĂŒrgen (ed.), 3432: 3414: 3387: 3335: 3041: 2279:. The quest for a quantum version of general relativity addresses one of the most fundamental 2272: 2101: 1455: 1353: 1216: 1109:
Two bodies falling towards the center of the Earth accelerate towards each other as they fall.
1042: 795: 565: 515: 290: 6093: 6010: 5760: 5700: 5690: 5637: 5614: 5192: 4847: 4837: 4733: 4664: 4656: 4479: 4469: 4340: 4268: 4214: 4093: 4049: 4015: 3941: 3809:
The Elegant Universe: Superstrings, Hidden Dimensions, and the Quest for the Ultimate Theory
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Matter falling onto a compact object is one of the most efficient mechanisms for releasing
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Albert Einstein â€“ Chief Engineer of the Universe: Einstein's Life and Work in Context
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A review of the various problems and the techniques being developed to overcome them, see
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strong gravitational fields. This has become possible thanks to precision observations of
1844: 1828: 1820: 1800: 1767: 1724: 1524: 1220: 917: 901: 889: 803: 695: 670: 555: 550: 414: 295: 257: 32: 5558: 3602:(1997), "Local and Global Light Bending in Einstein's and other Gravitational Theories", 2988:
Introductions to gravitational lensing and its applications can be found on the webpages
2187:
One of the most important aspects of general relativity is that it can be applied to the
1694:
Newtonian (red) vs. Einsteinian orbit (blue) of a single planet orbiting a spherical star
465: 4833: 4652: 4605: 4465: 4336: 4264: 4245: 4210: 4089: 4011: 3937: 3841: 3769: 3697: 3615: 3583: 3363: 3313: 3029: 2744:
A simple explanation of mass–energy equivalence can be found in sections 3.8 and 3.9 of
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Einstein's struggle to find the correct field equations is traced in chapters 13–15 of
2596:, p. 47–61. More complete treatments on a fairly elementary level can be found e.g. in 2209: 1992: 1926: 1840: 1816: 1747: 1616: 1432: 1428: 1345: 1219:, Einstein's former mathematics professor at the Swiss Federal Polytechnic, introduced 1124: 955: 738: 705: 700: 388: 252: 37: 4356: 4218: 3994:
Proceedings of the 7th Conference on the History of General Relativity, Tenerife, 2005
3591: 1897:; strictly speaking, all measurements of gravitational time dilation are tests of the 1489:
Distances, at different latitudes, corresponding to 30 degrees difference in longitude
6082: 5790: 5770: 5765: 5680: 5548: 5376: 5320: 5152: 5105: 4807: 4786: 4390: 4371: 4352: 4272: 4149: 4027: 3641: 3053: 2512: 2288: 2019: 1883: 1852: 1751: 1743: 1479: 1447: 1326: 1314: 1294: 665: 625: 580: 560: 485: 383: 262: 3953: 3713: 3506: 3102:. For an up-to-date account of the role of black holes in structure formation, see 2653: 6065: 6022: 5810: 5730: 5695: 5225: 5187: 4691: 4684: 4593: 4367: 4168: 4115: 3827: 3802: 3795: 3037: 2783:
The geometrical meaning of Einstein's equations is explored in chapters 7 and 8 of
2248: 2027: 1988: 1955: 1910: 1856: 1792: 1683: 1349: 1245:
The geometry of general curved surfaces was developed in the early 19th century by
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More specifically, Einstein's calculations, which are described in chapter 11b of
1021:
An observer in an accelerated reference frame must introduce what physicists call
26: 4907: 4869: 3470: 3140:
An elementary introduction to the black hole uniqueness theorems can be found in
2023: 928:, which describes the mutual attraction experienced by bodies due to their mass. 5842: 5594: 5563: 5110: 4624:"Simulations of the formation, evolution and clustering of galaxies and quasars" 4145: 4019: 2324: 2320: 2252: 1973: 1954:
places in the night sky. This kind of focussing is well known when it comes to
1879: 1781: 1780:. It is also seen in astrophysical measurements, notably for light escaping the 1655: 1424: 1322: 925: 869: 799: 500: 470: 4097: 2791:. An introduction using only very simple mathematics is given in chapter 19 of 982: 5805: 5371: 5215: 5210: 4980:, featuring an elementary introduction to general relativity, black holes and 4712: 4554: 3623: 3216:
With a focus on string theory, the search for quantum gravity is described in
3157:
Detailed information can be found in Ned Wright's Cosmology Tutorial and FAQ,
2645: 2463: 2152: 2097: 2086: 2007: 1875: 1824: 1651: 1239: 857: 845:. Many of these predictions have been confirmed by experiment or observation, 710: 272: 198: 3674:
Friedrich, Helmut (2005), "Is general relativity 'essentially understood'?",
2315:
Other attempts to modify general relativity have been made in the context of
1913:; the success of these models is further testament to the theory's validity. 1682:
was accepted because it accounted for the motion of planets and moons in the
1249:. This geometry had in turn been generalized to higher-dimensional spaces in 936:
involving an observer in free fall to his fully geometric theory of gravity.
5202: 2316: 2197: 2180: 2151:, in which focused beams of matter are flung away into space at speeds near 2136: 1921: 1893:
A number of other tests have probed the validity of various versions of the
1639: 1498: 1330: 1321:, this is equivalent to saying that such test particles move along straight 1318: 1235: 1232: 1176: 1068: 1064: 951: 861: 807: 281: 41: 4861: 4676: 4493: 4442:
Poisson, Eric (2004), "The Motion of Point Particles in Curved Spacetime",
4226: 3945: 3787: 3705: 3651:(1917), "Kosmologische Betrachtungen zur allgemeinen RelativitÀtstheorie", 3391: 3339: 3045: 1795:
to altitudes of between tens and tens of thousands of kilometers (first by
4344: 2895:, Mercury on pp. 253–254, Einstein's rise to fame in sections 16b and 16c. 1815:
Further tests of general relativity include precision measurements of the
1746:
in the stars' positions in the sky (an arc second is equal to 1/3600 of a
1485: 1277:
in late 1915, culminating in his final presentation on November 25, 1915.
1269:
influences spacetime's curvature. Having formulated what are now known as
5745: 5095: 4668: 4643: 4044: 2309: 2221: 2188: 2070: 2066: 1784: 1494: 1451: 1443: 1436: 1373: 1334: 1204: 1192: 1181: 1174:
A deeper analogy relates tidal forces with a property of surfaces called
1152: 1128: 1056: 873: 650: 460: 300: 4951:
Additional resources, including more advanced material, can be found in
4842: 4660: 4474: 3664: 3372: 1754:. In this way, a British expedition to West Africa in 1919, directed by 4960: 4810:(2006), "The Confrontation between General Relativity and Experiment", 3563: 2854:; Soldner's original derivation in the framework of Newton's theory is 2614:
Marolf, Donald (1999), "Spacetime Embedding Diagrams for Black Holes",
2571:
Tides and their geometric interpretation are explained in chapter 5 of
2140: 2113: 2085:
Black hole-powered jet emanating from the central region of the galaxy
1712: 1646:
describes the geometry around a spherical, non-rotating mass such as a
1439:, contribute to that body's mass, and hence act as sources of gravity. 1357: 1341: 1291:
spacetime tells matter how to move; matter tells spacetime how to curve
130:{\displaystyle G_{\mu \nu }+\Lambda g_{\mu \nu }={\kappa }T_{\mu \nu }} 4927:
was created from a revision of this article dated 9 May 2021
4824: 4456: 4327: 4080: 3688: 3321: 3276: 2628: 2283:
in physics. While there are promising candidates for such a theory of
1658:
describes a rotating black hole. Still other solutions can describe a
1305: 1105: 5425: 4373:'Subtle is the Lord ...' The Science and life of Albert Einstein 4038:, Lecture Notes in Physics, vol. 648, Springer, pp. 33–54, 3411:
Einstein's Unfinished Symphony: Listening to the Sounds of Space-Time
3220:; for an account from the point of view of loop quantum gravity, see 2515:
between certain inertial frames. For simple derivations of this, see
2243: 2205: 2132: 2125: 1950: 1946: 1930: 1860: 1763: 1704: 1410: 1266: 833:. General relativity also predicts novel effects of gravity, such as 830: 3778: 3555: 2238:
Einstein's equations can be generalized by adding a term called the
2183:
emitted no more than a few hundred thousand years after the Big Bang
872:). General relativity is also part of the framework of the standard 6017: 4070:
Lehner, Luis (2002), "Numerical Relativity: Status and Prospects",
4053: 3020: 2081: 4002: 2080: 2057:
are in operation, and a mission to launch a space-based detector,
2014: 1843:. The geodetic and frame-dragging effects were both tested by the 1732: 1700: 1689: 1484: 1304: 1228: 1208: 1041: 981: 963: 921: 852:
General relativity has developed into an essential tool in modern
822: 25: 3833:
The Fabric of the Cosmos: Space, Time, and the Texture of Reality
1890:) are testament to the validity of the relativistic predictions. 1585:{\displaystyle \mathbf {G} ={\frac {8\pi G}{c^{4}}}\mathbf {T} ,} 1262:
are used to illustrate curved spacetime in educational contexts.
5406: 3919:"Of pots and holes: Einstein's bumpy road to general relativity" 3182:; good descriptions of more modern developments can be found in 2822: 2228: 2176: 2105: 2096:
region of space, general relativity predicts the formation of a
1999: 1969: 1836: 1708: 1666:, an expanding universe. The simplest solution is the uncurved 1647: 1399: 1132: 5846: 4990: 2669:, chapters 8 and 9 for vivid illustrations of curved spacetime. 1819:
or gravitational time delay for light, measured in 2002 by the
1527:, which describes some aspects of the way spacetime is curved. 1289:, Einstein's geometric theory of gravity can be summarized as: 2808:; for a (technical) summary of our current understanding, see 2121: 1887: 856:. It provides the foundation for the current understanding of 45: 4986: 4772:, Scientific American Library, San Francisco: W. H. Freeman, 4698:, Einstein Studies, vol. 1, BirkhĂ€user, pp. 48–62, 2975:
The geometry of such situations is explored in chapter 23 of
2958:
An accessible introduction to tests of general relativity is
1958:, and hence the corresponding gravitational effect is called 1909:
Models based on general relativity play an important role in
1231:
but also time. The basic entity of this new geometry is four-
4905: 3653:
Sitzungsberichte der Preußischen Akademie der Wissenschaften
3431:(1989 reprinted ed.), Institute of Physics Publishing, 2061:, is currently under development, with a precursor mission ( 3472:
Ripples on a Cosmic Sea. The Search for Gravitational Waves
3081:
The ongoing search for gravitational waves is described in
1839:). Another, which is related to rotating masses, is called 864:
emitted by certain types of astronomical objects (such as
3103: 4717:
Black Holes and Time Warps: Einstein's Outrageous Legacy
2575:. This part of the historical development is traced in 1766:
by the Sun, which utilize highly accurate techniques of
1719:. The first measurement of this effect, for the planet 1599:(which measures curvature) is equated with the quantity 1167:(in which the coordinate lines are straight lines) to a 4415:"The equivalence principle and the deflection of light" 3861:
A Non-mathematical Proof of Gravitational Time Dilation
3756:
Gnedin, Nickolay Y. (2005), "Digitizing the Universe",
1325:
in spacetime. In the presence of gravity, spacetime is
1207: â€“ are traditionally defined in three-dimensional 3106:; a brief summary can be found in the related article 2825:
measurements of planetary positions; see chapter 5 of
1776:
was first measured in a laboratory setting in 1959 by
1442:
In special relativity, energy is closely connected to
5970: 2355:
Introduction to the mathematics of general relativity
1540: 73: 4175:
It's About Time. Understanding Einstein's Relativity
1622:
This equation is often referred to in the plural as
1078:
This gravitational frequency shift corresponds to a
888:
to produce a complete and self-consistent theory of
5952: 5904: 5878: 5658: 5523: 5495: 5364: 5313: 5275: 5254: 5243: 5201: 5145: 5129: 5071: 5035: 5024: 3542:Cowen, Ron (2001), "A Dark Force in the Universe", 3515:"How many different kinds of black hole are there?" 4172: 3896: 3806: 1584: 129: 3570:Disney, Michael (1998), "A New Look at Quasars", 2908:Gravity Probe B Science Results—NASA Final Report 2858:. For the most precise measurements to date, see 2804:The most important solutions are listed in every 1835:(high-precision measurements of the orbit of the 1670:, the spacetime described by special relativity. 30:High-precision test of general relativity by the 3899:The Little Book of the Big Bang. A Cosmic Primer 2415:. A precis of Newtonian gravity can be found in 1827:travelling through space. One of these effects, 966:travels along straight lines at constant speed. 4978:National Center for Supercomputing Applications 4598:Galaxies in the universe â€“ An introduction 4246:"What was Einstein's principle of equivalence?" 3120: 2558:These and other tidal effects are described in 1171:(where coordinate lines need not be straight). 4965:Max Planck Institute for Gravitational Physics 4918: 4748:Max Planck Institute for Gravitational Physics 4738:"Gravitational redshift and White Dwarf stars" 4696:Einstein and the History of General Relativity 4425:Max Planck Institute for Gravitational Physics 4036:Astrophysics, Clocks and Fundamental Constants 3525:Max Planck Institute for Gravitational Physics 3295:"Relativity and the Global Positioning System" 2880: 2501:associated with such an accelerated observer). 2092:When mass is concentrated into a sufficiently 1595:i.e., up to a constant multiple, the quantity 5858: 5002: 4308:"The quest to understand the Pioneer anomaly" 3348:"Relativity in the Global Positioning System" 3086: 2542: 772: 8: 4253:Studies in History and Philosophy of Science 2432:This is described in detail in chapter 2 of 2267:In contrast to all other modern theories of 2159:Another reason follows from what are called 1859:orbit each other. At least one of them is a 1855:. In such a star system, two highly compact 1664:Friedmann–LemaĂźtre–Robertson–Walker solution 2855: 2275:theory: it does not include the effects of 2124:are assumed to reside in the cores of most 1063:; the second observer will measure a lower 818:extremely successful at describing motion. 5865: 5851: 5843: 5251: 5032: 5009: 4995: 4987: 3666:Relativity. The special and general theory 2962:; a more technical, up-to-date account is 2380:Derivations of the Lorentz transformations 1015: 841:and an effect of gravity on time known as 779: 765: 331: 221: 51: 4874:, University of California at Los Angeles 4851: 4841: 4823: 4642: 4483: 4473: 4455: 4326: 4079: 4043: 4001: 3777: 3687: 3631: 3381: 3371: 3329: 3250: 3141: 3082: 3069: 3019: 2905:Everitt, C.W.F.; Parkinson, B.W. (2009), 2872: 2851: 2847: 2809: 2627: 2407:, p. 110ff., in chapters 9 through 15 of 1791:effect has been measured by transporting 1574: 1566: 1549: 1541: 1539: 1093:In a similar way, Einstein predicted the 118: 109: 97: 78: 72: 4935:, and does not reflect subsequent edits. 3238: 3187: 3179: 2859: 2545:; for a non-technical presentation, see 2516: 2255: â€“ has steadily been accumulating. 2170: 1920: 1223:, a geometric formulation of Einstein's 1104: 5977: 3429:Principles of Cosmology and Gravitation 3234: 3204: 2993: 2989: 2784: 2771: 2758: 2745: 2732: 2718: 2692: 2666: 2601: 2572: 2559: 2471: 2459: 2433: 2412: 2396: 1603:(which measures matter content). Here, 932:between 1907 and 1915, from his simple 401: 375: 334: 280: 54: 3263: 3221: 3217: 3200: 3169:provides a more thorough presentation. 3158: 3145: 3128: 3124: 3107: 3099: 3065: 2976: 2929: 2792: 2788: 2705: 2597: 2593: 2589: 2546: 2529: 2470:and their gravitational analogue, cf. 2446: 2416: 2303:which predict that such singularities 2175:An image, created using data from the 2002:team announced that they had directly 1340:A simple analogy is the following: In 916:(the interaction between objects with 813:By the beginning of the 20th century, 3740:Special relativity. A first encounter 3183: 3166: 3162: 2946: 2942: 2879:. For the Sirius B measurements, see 2843: 2842:For the historical measurements, see 1949:can pass along one side of a massive 1227:where the geometry included not only 815:Newton's law of universal gravitation 7: 4770:A Journey Into Gravity and Spacetime 2963: 2959: 2892: 2876: 2830: 2826: 2679: 2576: 2494: 2420: 2408: 2404: 1799:in 1971; most accurately to date by 1707:traces around a perfectly spherical 1699:Newtonian gravity predicts that the 1135:in the Earth's oceans, so the term " 16:Theory of gravity by Albert Einstein 5581:Tolman–Oppenheimer–Volkoff equation 5534:Friedmann–LemaĂźtre–Robertson–Walker 2403:This development is traced e.g. in 2385:List of books on general relativity 1937:(the much closer foreground galaxy 1882:. Such systems rely on two sets of 1638:describes a particular geometry of 1402:. In Einstein's theory and related 4577:von Soldner, Johann Georg (1804), 3604:General Relativity and Gravitation 3161:; a very readable introduction is 2616:General Relativity and Gravitation 2053:Currently, a number of land-based 1929:: four images of the same distant 1810:alternatives to general relativity 1508:, which describes exactly how the 1238:. The orbits of moving bodies are 896:From special to general relativity 90: 14: 5351:Hamilton–Jacobi–Einstein equation 4219:10.1038/scientificamerican0802-42 3592:10.1038/scientificamerican0698-52 1995:, which are a different concept. 1409:The equivalence between mass and 1095:gravitational deflection of light 847:most recently gravitational waves 6064: 6052: 6040: 6028: 6016: 6004: 5992: 5980: 5829: 5828: 4917: 4585:Berliner Astronomisches Jahrbuch 4195:"Does dark matter really exist?" 3976:One hundred authors for Einstein 3879:One hundred authors for Einstein 3450:One hundred authors for Einstein 2069:fractions of a second after the 1575: 1542: 1364:test particles in free fall are 1087: 1072: 746: 745: 732: 62: 3996:, vol. 0709, p. 685, 3978:, Wiley-VCH, pp. 178–181, 3881:, Wiley-VCH, pp. 182–187, 3724:, University of Chicago Press, 3452:, Wiley-VCH, pp. 402–405, 2038:The discoverers of PSR1913+16, 1998:In February 2016, the Advanced 1874:that are used for both precise 1396:Newton's description of gravity 1301:Probing the gravitational field 1139:" is used for this phenomenon. 5158:Mass–energy equivalence (E=mc) 4600:, Cambridge University Press, 4560:Three Roads to Quantum Gravity 4540:, Cambridge University Press, 4306:Nieto, Michael Martin (2006), 4288:Gravitational lensing webpages 4179:, Princeton University Press, 3722:General relativity from A to B 3633:11858/00-001M-0000-0013-5AB5-4 3207:, section 34.1 and chapter 30. 3038:10.1103/PhysRevLett.116.061102 2806:textbook on general relativity 2242:. When this term is present, 2161:black-hole uniqueness theorems 1899:weak version of that principle 1833:Lunar Laser Ranging Experiment 1413:, as expressed by the formula 1: 5873:Introductory science articles 4596:; Gallagher, John S. (2007), 4151:What Remains To Be Discovered 3178:Einstein's original paper is 2365:History of general relativity 1636:A solution of these equations 1147:From acceleration to geometry 1052:gravitational frequency shift 4953:General relativity resources 4719:, W W Norton & Company, 4273:10.1016/0039-3681(85)90002-0 4128:Imagine the Universe Website 3489:Caldwell, Robert R. (2004), 3352:Living Reviews in Relativity 3277:Living Reviews in Relativity 2179:satellite telescope, of the 2055:gravitational wave detectors 2004:observed gravitational waves 1868:satellite navigation systems 1275:Prussian Academy of Sciences 1225:special theory of relativity 1059:, as may be calculated from 1050:The first new effect is the 5173:Relativistic Doppler effect 4793:, Oxford University Press, 4536:Schutz, Bernard F. (2003), 4376:, Oxford University Press, 4130:, NASA GSFC, archived from 4020:10.1016/j.shpsa.2012.07.010 3858:Harrison, David M. (2002), 3742:, Oxford University Press, 3121:Sparke & Gallagher 2007 2499:inertial frame of reference 2370:Tests of general relativity 2333:modified Newtonian dynamics 1831:, has been tested with the 1789:gravitational time dilation 1165:Cartesian coordinate system 1080:gravitational time dilation 1028:Newton's law of gravitation 843:gravitational time dilation 243:Gravitational time dilation 6110: 5644:In computational physics: 5168:Relativity of simultaneity 4972:. Website produced by the 4871:Cosmology tutorial and FAQ 4736:; Barstow, Martin (2007), 4538:Gravity from the ground up 4500:Renn, JĂŒrgen, ed. (2005), 4193:Milgrom, Mordehai (2002), 4122:Lochner, Jim, ed. (2007), 4098:10.1142/9789812776556_0010 3738:Giulini, Domenico (2005), 3469:; McNamara, Geoff (1997), 3427:Berry, Michael V. (1989), 3409:Bartusiak, Marcia (2000), 2881:Trimble & Barstow 2007 2821:More precisely, these are 2271:, general relativity is a 2192:universe is approximately 1905:Astrophysical applications 1888:universal coordinated time 1717:anomalous perihelion shift 1611:of Newtonian gravity, and 1191:The elementary objects of 943: 363:Mathisson–Papapetrou–Dixon 204:Pseudo-Riemannian manifold 18: 5826: 5481:Lense–Thirring precession 5063:Doubly special relativity 3513:Chrusciel, Piotr (2006), 3507:10.1088/2058-7058/17/5/36 3087:Blair & McNamara 1997 2543:Ehlers & Rindler 1997 2466:, Einstein also explored 2310:beginning of the universe 2032:electromagnetic radiation 1872:Global Positioning System 1619:from special relativity. 1465: 5341:Post-Newtonian formalism 5331:Einstein field equations 5267:Mathematical formulation 5091:Hyperbolic orthogonality 4244:Norton, John D. (1985), 3917:Janssen, Michel (2005), 3895:Hogan, Craig J. (1999), 3203:, pp. 52–59 and 98–122; 2269:fundamental interactions 2110:supermassive black holes 1812:that had been proposed. 1506:Riemann curvature tensor 1281:Geometry and gravitation 1169:curved coordinate system 978:Gravity and acceleration 904:published his theory of 368:Hamilton–Jacobi–Einstein 348:Einstein field equations 171:Mathematical formulation 44:(blue lines) due to the 5052:Galilean transformation 5043:Principle of relativity 4970:NCSA Spacetime Wrinkles 4124:"Gravitational Lensing" 3720:Geroch, Robert (1978), 3624:10.1023/A:1018843001842 3008:Physical Review Letters 2945:; details are given in 2646:10.1023/A:1026646507201 2297:spacetime singularities 1966:Observational astronomy 1680:Newton's law of gravity 1662:or, in the case of the 1626:, since the quantities 1404:theories of gravitation 1378:the center of the Earth 910:Newton's laws of motion 5932:mathematical formalism 5137:Lorentz transformation 4913: 4893:Listen to this article 4520:Active galactic nuclei 4285:Newbury, Pete (1997), 3946:10.1002/andp.200410130 3706:10.1002/andp.200510173 2184: 2145:active galactic nuclei 2089: 2048:Nobel Prize in Physics 1942: 1774:Gravitational redshift 1695: 1644:Schwarzschild solution 1609:gravitational constant 1586: 1514:energy–momentum tensor 1490: 1460:energy–momentum tensor 1310: 1211:or on two-dimensional 1110: 1047: 987: 866:active galactic nuclei 238:Gravitational redshift 131: 49: 5605:Weyl−Lewis−Papapetrou 5346:Raychaudhuri equation 5285:Equivalence principle 4912: 4504:, Berlin: Wiley-VCH, 3233:For dark matter, see 2240:cosmological constant 2174: 2108:. On the other hand, 2084: 1960:gravitational lensing 1924: 1917:Gravitational lensing 1895:equivalence principle 1693: 1587: 1488: 1308: 1108: 1045: 1034:Physical consequences 985: 972:equivalence principle 962:: observers for whom 954:elevator experiences 946:Equivalence principle 940:Equivalence principle 839:gravitational lensing 526:Weyl−Lewis−Papapetrou 481:Kerr–Newman–de Sitter 301:Einstein–Rosen bridge 233:Gravitational lensing 189:Equivalence principle 132: 29: 5646:Numerical relativity 5487:pulsar timing arrays 4974:numerical relativity 4944:More spoken articles 4868:Wright, Ned (2007), 4812:Living Rev. Relativ. 4518:Robson, Ian (1996), 4444:Living Rev. Relativ. 3346:Ashby, Neil (2003), 3293:Ashby, Neil (2002), 3104:Springel et al. 2005 2375:Numerical relativity 2301:singularity theorems 2293:loop quantum gravity 1624:Einstein's equations 1538: 1471:Einstein's equations 1466:Einstein's equations 1271:Einstein's equations 1247:Carl Friedrich Gauss 456:Einstein–Rosen waves 182:Fundamental concepts 71: 5538:Friedmann equations 5432:Hulse–Taylor binary 5394:Gravitational waves 5290:Riemannian geometry 5116:Proper acceleration 5101:Maxwell's equations 5047:Galilean relativity 4982:gravitational waves 4843:10.12942/lrr-2006-3 4834:2006LRR.....9....3W 4791:Was Einstein Right? 4661:10.1038/nature03597 4653:2005Natur.435..629S 4606:2007gitu.book.....S 4475:10.12942/lrr-2004-6 4466:2004LRR.....7....6P 4413:Pössel, M. (2007), 4396:The Road to Reality 4345:10.1051/epn:2006604 4337:2006ENews..37f..30N 4265:1985SHPSA..16..203N 4211:2002SciAm.287b..42M 4199:Scientific American 4090:2002grg..conf..210L 4012:2007arXiv0709.0685K 3938:2005AnP...517S..58J 3842:2004fcst.book.....G 3770:2005Natur.435..572G 3698:2006AnP...518...84F 3616:1997GReGr..29..519E 3584:1998SciAm.278f..52D 3572:Scientific American 3373:10.12942/lrr-2003-1 3364:2003LRR.....6....1A 3314:2002PhT....55e..41A 3237:; for dark energy, 3030:2016PhRvL.116f1102A 2829:and section 3.5 of 2638:1999GReGr..31..919M 2604:, chapters 8 and 9. 2224: â€“ roughly 14 2202:cosmological models 2143:and other types of 2046:, were awarded the 1985:Gravitational waves 1980:Gravitational waves 1829:geodetic precession 1668:Minkowski spacetime 1642:; for example, the 1529:Einstein's equation 1510:Riemannian manifold 1476:Riemannian geometry 1431:of systems such as 1366:spacetime geodesics 1251:Riemannian geometry 1240:curves in spacetime 908:, which reconciles 900:In September 1905, 835:gravitational waves 410:Kaluza–Klein theory 296:Minkowski spacetime 248:Gravitational waves 6089:General relativity 5927:general relativity 5587:Reissner–Nordström 5505:Brans–Dicke theory 5336:Linearized gravity 5163:Length contraction 5081:Frame of reference 5058:Special relativity 4914: 3926:Annalen der Physik 3676:Annalen der Physik 3669:, Crown Publishers 2717:See chapter 10 of 2528:See chapter 12 of 2468:centrifugal forces 2360:Special relativity 2350:General relativity 2185: 2090: 1943: 1935:gravitational lens 1803:launched in 1976). 1797:Hafele and Keating 1696: 1660:gravitational wave 1582: 1491: 1390:Sources of gravity 1311: 1260:Embedding Diagrams 1111: 1061:special relativity 1048: 988: 960:special relativity 934:thought experiment 906:special relativity 792:General relativity 739:Physics portal 511:Oppenheimer–Snyder 451:Reissner–Nordström 343:Linearized gravity 291:Spacetime diagrams 194:Special relativity 127: 56:General relativity 50: 40:by the warping of 21:General relativity 5968: 5967: 5960:systolic geometry 5944:quantum mechanics 5840: 5839: 5654: 5653: 5633:OzsvĂĄth–SchĂŒcking 5239: 5238: 5221:Minkowski diagram 5178:Thomas precession 5121:Relativistic mass 4910: 4808:Will, Clifford M. 4787:Will, Clifford M. 4734:Trimble, Virginia 4637:(7042): 629–636, 4615:978-0-521-85593-8 4107:978-981-238-171-2 4063:978-3-540-21967-5 3764:(7042): 572–573, 3600:Rindler, Wolfgang 3420:978-0-425-18620-6 3322:10.1063/1.1485583 3119:See chapter 8 of 2875:and chapter 3 of 2787:; cf. box 2.6 in 2757:See chapter 6 of 2562:, pp. 83–91. 2231:ago and has been 2112:with the mass of 1572: 1531:then states that 1523:, now called the 1354:line of longitude 1217:Hermann Minkowski 1161:fictitious forces 1125:center of gravity 1116:fictitious forces 1023:fictitious forces 789: 788: 422: 421: 308: 307: 6101: 6069: 6068: 6057: 6056: 6055: 6045: 6044: 6043: 6033: 6032: 6031: 6021: 6020: 6009: 6008: 6007: 5997: 5996: 5985: 5984: 5976: 5912:electromagnetism 5867: 5860: 5853: 5844: 5832: 5831: 5615:van Stockum dust 5387:Two-body problem 5305:Mach's principle 5252: 5193:Terrell rotation 5033: 5011: 5004: 4997: 4988: 4934: 4932: 4921: 4920: 4911: 4901: 4899: 4894: 4881: 4880: 4879: 4864: 4855: 4845: 4827: 4803: 4782: 4766:Wheeler, John A. 4761: 4760: 4759: 4750:, archived from 4729: 4708: 4687: 4646: 4644:astro-ph/0504097 4628: 4618: 4594:Sparke, Linda S. 4588: 4582: 4573: 4550: 4532: 4514: 4496: 4487: 4477: 4459: 4438: 4437: 4436: 4427:, archived from 4409: 4386: 4363: 4361: 4355:, archived from 4330: 4315:Europhysics News 4312: 4302: 4301: 4300: 4291:, archived from 4281: 4280: 4279: 4250: 4240: 4239: 4238: 4229:, archived from 4189: 4178: 4169:Mermin, N. David 4164: 4141: 4140: 4139: 4118: 4083: 4066: 4047: 4045:astro-ph/0405178 4030: 4005: 3988: 3970: 3969: 3968: 3962: 3956:, archived from 3923: 3913: 3902: 3891: 3873: 3872: 3871: 3866: 3854: 3823: 3812: 3798: 3781: 3752: 3734: 3716: 3691: 3670: 3661:Einstein, Albert 3656: 3649:Einstein, Albert 3644: 3635: 3598:Ehlers, JĂŒrgen; 3594: 3566: 3538: 3537: 3536: 3527:, archived from 3509: 3485: 3462: 3441: 3423: 3405: 3404: 3403: 3394:, archived from 3385: 3375: 3342: 3333: 3299: 3280: 3273: 3267: 3260: 3254: 3247: 3241: 3231: 3225: 3214: 3208: 3197: 3191: 3176: 3170: 3155: 3149: 3138: 3132: 3117: 3111: 3096: 3090: 3079: 3073: 3063: 3057: 3056: 3023: 3003: 2997: 2986: 2980: 2973: 2967: 2956: 2950: 2939: 2933: 2927: 2921: 2920: 2919: 2918: 2913: 2902: 2896: 2890: 2884: 2869: 2863: 2856:von Soldner 1804 2840: 2834: 2819: 2813: 2802: 2796: 2781: 2775: 2768: 2762: 2755: 2749: 2742: 2736: 2728: 2722: 2715: 2709: 2702: 2696: 2689: 2683: 2676: 2670: 2663: 2657: 2656: 2631: 2611: 2605: 2586: 2580: 2569: 2563: 2556: 2550: 2539: 2533: 2526: 2520: 2508: 2502: 2491: 2485: 2481: 2475: 2456: 2450: 2443: 2437: 2430: 2424: 2401: 2329:cosmic expansion 2218:particle physics 2208:content, namely 1933:, produced by a 1760:May 1919 eclipse 1756:Arthur Eddington 1725:radio telescopes 1591: 1589: 1588: 1583: 1578: 1573: 1571: 1570: 1561: 1550: 1545: 1255:Bernhard Riemann 1007:standard gravity 781: 774: 767: 754: 749: 748: 741: 737: 736: 521:van Stockum dust 506:Robertson–Walker 332: 222: 136: 134: 133: 128: 126: 125: 113: 105: 104: 86: 85: 66: 52: 6109: 6108: 6104: 6103: 6102: 6100: 6099: 6098: 6079: 6078: 6075: 6063: 6053: 6051: 6041: 6039: 6029: 6027: 6015: 6005: 6003: 5991: 5979: 5971: 5969: 5964: 5948: 5900: 5874: 5871: 5841: 5836: 5822: 5650: 5554:BKL singularity 5544:LemaĂźtre–Tolman 5519: 5515:Quantum gravity 5497: 5491: 5477:geodetic effect 5451:(together with 5421:LISA Pathfinder 5360: 5309: 5295:Penrose diagram 5277: 5271: 5246: 5235: 5231:Minkowski space 5197: 5141: 5125: 5073: 5067: 5027: 5020: 5015: 4961:Einstein Online 4948: 4947: 4936: 4930: 4928: 4925:This audio file 4922: 4915: 4906: 4903: 4897: 4896: 4892: 4889: 4884: 4877: 4875: 4867: 4806: 4801: 4785: 4780: 4764: 4757: 4755: 4743:Einstein Online 4732: 4727: 4711: 4706: 4690: 4626: 4621: 4616: 4592: 4576: 4571: 4553: 4548: 4535: 4530: 4517: 4512: 4499: 4441: 4434: 4432: 4420:Einstein Online 4412: 4407: 4399:, A. A. Knopf, 4389: 4384: 4366: 4359: 4310: 4305: 4298: 4296: 4284: 4277: 4275: 4248: 4243: 4236: 4234: 4192: 4187: 4167: 4162: 4144: 4137: 4135: 4121: 4108: 4074:, p. 210, 4069: 4064: 4033: 3991: 3986: 3973: 3966: 3964: 3960: 3921: 3916: 3911: 3894: 3889: 3876: 3869: 3867: 3864: 3857: 3852: 3836:, A. A. Knopf, 3826: 3821: 3801: 3779:10.1038/435572a 3755: 3750: 3737: 3732: 3719: 3682:(1–2): 84–108, 3673: 3659: 3647: 3597: 3569: 3556:10.2307/3981642 3550:(14): 218–220, 3541: 3534: 3532: 3520:Einstein Online 3512: 3488: 3483: 3465: 3460: 3446:Bertotti, Bruno 3444: 3439: 3426: 3421: 3408: 3401: 3399: 3345: 3297: 3292: 3288: 3283: 3274: 3270: 3261: 3257: 3248: 3244: 3232: 3228: 3215: 3211: 3198: 3194: 3177: 3173: 3156: 3152: 3139: 3135: 3118: 3114: 3097: 3093: 3080: 3076: 3068:, pp. 317–321; 3064: 3060: 3005: 3004: 3000: 2987: 2983: 2974: 2970: 2957: 2953: 2940: 2936: 2928: 2924: 2916: 2914: 2911: 2904: 2903: 2899: 2891: 2887: 2870: 2866: 2841: 2837: 2820: 2816: 2803: 2799: 2782: 2778: 2769: 2765: 2756: 2752: 2743: 2739: 2729: 2725: 2716: 2712: 2703: 2699: 2690: 2686: 2677: 2673: 2664: 2660: 2613: 2612: 2608: 2587: 2583: 2570: 2566: 2557: 2553: 2540: 2536: 2527: 2523: 2509: 2505: 2492: 2488: 2482: 2478: 2457: 2453: 2444: 2440: 2431: 2427: 2402: 2398: 2394: 2389: 2345: 2285:quantum gravity 2277:quantum physics 2261: 2259:Modern research 2169: 2135:in the form of 2079: 2063:LISA Pathfinder 1982: 1919: 1907: 1845:Gravity Probe B 1801:Gravity Probe A 1778:Pound and Rebka 1768:radio astronomy 1735:and the Earth). 1703:which a single 1676: 1562: 1551: 1536: 1535: 1525:Einstein tensor 1468: 1392: 1303: 1283: 1221:Minkowski space 1149: 1103: 1036: 980: 948: 942: 918:electric charge 914:electrodynamics 902:Albert Einstein 898: 890:quantum gravity 886:quantum physics 804:Albert Einstein 785: 744: 731: 730: 723: 722: 546: 545: 536: 535: 491:LemaĂźtre–Tolman 436: 435: 424: 423: 415:Quantum gravity 402:Advanced theory 329: 328: 327: 310: 309: 258:Geodetic effect 219: 218: 209: 208: 184: 183: 167: 137: 114: 93: 74: 69: 68: 24: 17: 12: 11: 5: 6107: 6105: 6097: 6096: 6091: 6081: 6080: 6074: 6073: 6061: 6049: 6037: 6025: 6013: 6001: 5989: 5966: 5965: 5963: 5962: 5956: 5954: 5950: 5949: 5947: 5946: 5941: 5936: 5935: 5934: 5924: 5919: 5914: 5908: 5906: 5902: 5901: 5899: 5898: 5893: 5888: 5882: 5880: 5876: 5875: 5872: 5870: 5869: 5862: 5855: 5847: 5838: 5837: 5827: 5824: 5823: 5821: 5820: 5813: 5808: 5803: 5798: 5793: 5788: 5783: 5778: 5773: 5768: 5763: 5758: 5753: 5748: 5743: 5741:Choquet-Bruhat 5738: 5733: 5728: 5723: 5718: 5713: 5708: 5703: 5698: 5693: 5688: 5683: 5678: 5673: 5668: 5662: 5660: 5656: 5655: 5652: 5651: 5649: 5648: 5641: 5640: 5635: 5630: 5623: 5622: 5617: 5612: 5607: 5602: 5593:Axisymmetric: 5590: 5589: 5584: 5578: 5567: 5566: 5561: 5556: 5551: 5546: 5541: 5532:Cosmological: 5529: 5527: 5521: 5520: 5518: 5517: 5512: 5507: 5501: 5499: 5493: 5492: 5490: 5489: 5484: 5473:frame-dragging 5470: 5465: 5460: 5457:Einstein rings 5453:Einstein cross 5446: 5435: 5434: 5429: 5423: 5418: 5413: 5400: 5390: 5389: 5384: 5379: 5374: 5368: 5366: 5362: 5361: 5359: 5358: 5356:Ernst equation 5353: 5348: 5343: 5338: 5333: 5328: 5326:BSSN formalism 5323: 5317: 5315: 5311: 5310: 5308: 5307: 5302: 5297: 5292: 5287: 5281: 5279: 5273: 5272: 5270: 5269: 5264: 5258: 5256: 5249: 5241: 5240: 5237: 5236: 5234: 5233: 5228: 5223: 5218: 5213: 5207: 5205: 5199: 5198: 5196: 5195: 5190: 5185: 5183:Ladder paradox 5180: 5175: 5170: 5165: 5160: 5155: 5149: 5147: 5143: 5142: 5140: 5139: 5133: 5131: 5127: 5126: 5124: 5123: 5118: 5113: 5108: 5103: 5098: 5093: 5088: 5086:Speed of light 5083: 5077: 5075: 5069: 5068: 5066: 5065: 5060: 5055: 5049: 5039: 5037: 5030: 5022: 5021: 5016: 5014: 5013: 5006: 4999: 4991: 4985: 4984: 4967: 4937: 4923: 4916: 4904: 4891: 4890: 4888: 4887:External links 4885: 4883: 4882: 4865: 4804: 4799: 4783: 4778: 4762: 4730: 4725: 4709: 4704: 4688: 4619: 4614: 4590: 4574: 4569: 4551: 4546: 4533: 4528: 4522:, John Wiley, 4515: 4510: 4497: 4439: 4410: 4405: 4391:Penrose, Roger 4387: 4382: 4364: 4303: 4282: 4259:(3): 203–246, 4241: 4190: 4185: 4165: 4160: 4142: 4119: 4106: 4067: 4062: 4054:10.1007/b13178 4031: 3989: 3984: 3971: 3914: 3909: 3892: 3887: 3874: 3855: 3850: 3824: 3819: 3799: 3753: 3748: 3735: 3730: 3717: 3671: 3657: 3645: 3610:(4): 519–529, 3595: 3567: 3539: 3510: 3486: 3481: 3463: 3458: 3442: 3437: 3424: 3419: 3406: 3343: 3289: 3287: 3284: 3282: 3281: 3268: 3255: 3251:Friedrich 2005 3242: 3226: 3209: 3192: 3171: 3150: 3148:, pp. 272–286. 3142:Chrusciel 2006 3133: 3112: 3091: 3083:Bartusiak 2000 3074: 3070:Bartusiak 2000 3058: 2998: 2981: 2968: 2951: 2934: 2922: 2897: 2885: 2873:Kennefick 2005 2864: 2852:Kennefick 2007 2848:Kennefick 2005 2835: 2814: 2810:Friedrich 2005 2797: 2776: 2763: 2750: 2737: 2723: 2710: 2697: 2691:E.g. p. xi in 2684: 2671: 2658: 2622:(6): 919–944, 2606: 2581: 2579:, section 12b. 2564: 2551: 2534: 2521: 2503: 2486: 2476: 2451: 2438: 2425: 2395: 2393: 2390: 2388: 2387: 2382: 2377: 2372: 2367: 2362: 2357: 2352: 2346: 2344: 2341: 2331:, for example 2281:open questions 2260: 2257: 2210:thermodynamics 2168: 2165: 2078: 2075: 1993:fluid dynamics 1981: 1978: 1956:optical lenses 1927:Einstein Cross 1918: 1915: 1906: 1903: 1853:binary pulsars 1841:frame-dragging 1817:Shapiro effect 1805: 1804: 1787:. The related 1771: 1736: 1675: 1672: 1654:, whereas the 1617:speed of light 1593: 1592: 1581: 1577: 1569: 1565: 1560: 1557: 1554: 1548: 1544: 1467: 1464: 1429:binding energy 1391: 1388: 1374:falling freely 1315:test particles 1302: 1299: 1295:test particles 1282: 1279: 1253:introduced by 1193:geometry  1148: 1145: 1102: 1099: 1035: 1032: 1011: 1010: 1003: 979: 976: 956:weightlessness 950:A person in a 944:Main article: 941: 938: 897: 894: 787: 786: 784: 783: 776: 769: 761: 758: 757: 756: 755: 742: 725: 724: 721: 720: 713: 708: 703: 698: 693: 688: 683: 678: 673: 668: 663: 658: 653: 648: 643: 638: 633: 628: 623: 618: 613: 608: 603: 598: 593: 588: 583: 578: 573: 568: 563: 558: 553: 547: 543: 542: 541: 538: 537: 534: 533: 528: 523: 518: 513: 508: 503: 498: 493: 488: 483: 478: 473: 468: 463: 458: 453: 448: 437: 431: 430: 429: 426: 425: 420: 419: 418: 417: 412: 404: 403: 399: 398: 397: 396: 394:Post-Newtonian 391: 386: 378: 377: 373: 372: 371: 370: 365: 360: 355: 350: 345: 337: 336: 330: 326: 325: 322: 318: 317: 316: 315: 312: 311: 306: 305: 304: 303: 298: 293: 285: 284: 278: 277: 276: 275: 270: 265: 260: 255: 253:Frame-dragging 250: 245: 240: 235: 230: 228:Kepler problem 220: 216: 215: 214: 211: 210: 207: 206: 201: 196: 191: 185: 181: 180: 179: 176: 175: 174: 173: 168: 166: 165: 160: 155: 149: 147: 139: 138: 124: 121: 117: 112: 108: 103: 100: 96: 92: 89: 84: 81: 77: 67: 59: 58: 15: 13: 10: 9: 6: 4: 3: 2: 6106: 6095: 6092: 6090: 6087: 6086: 6084: 6077: 6072: 6067: 6062: 6060: 6050: 6048: 6038: 6036: 6026: 6024: 6019: 6014: 6012: 6002: 6000: 5995: 5990: 5988: 5983: 5978: 5974: 5961: 5958: 5957: 5955: 5951: 5945: 5942: 5940: 5937: 5933: 5930: 5929: 5928: 5925: 5923: 5920: 5918: 5915: 5913: 5910: 5909: 5907: 5903: 5897: 5894: 5892: 5889: 5887: 5884: 5883: 5881: 5877: 5868: 5863: 5861: 5856: 5854: 5849: 5848: 5845: 5835: 5825: 5819: 5818: 5814: 5812: 5809: 5807: 5804: 5802: 5799: 5797: 5794: 5792: 5789: 5787: 5784: 5782: 5779: 5777: 5774: 5772: 5769: 5767: 5764: 5762: 5759: 5757: 5754: 5752: 5749: 5747: 5744: 5742: 5739: 5737: 5734: 5732: 5729: 5727: 5726:Chandrasekhar 5724: 5722: 5719: 5717: 5714: 5712: 5709: 5707: 5704: 5702: 5699: 5697: 5694: 5692: 5689: 5687: 5686:Schwarzschild 5684: 5682: 5679: 5677: 5674: 5672: 5669: 5667: 5664: 5663: 5661: 5657: 5647: 5643: 5642: 5639: 5636: 5634: 5631: 5629: 5625: 5624: 5621: 5618: 5616: 5613: 5611: 5608: 5606: 5603: 5600: 5596: 5592: 5591: 5588: 5585: 5582: 5579: 5577: 5573: 5572:Schwarzschild 5569: 5568: 5565: 5562: 5560: 5557: 5555: 5552: 5550: 5547: 5545: 5542: 5539: 5535: 5531: 5530: 5528: 5526: 5522: 5516: 5513: 5511: 5508: 5506: 5503: 5502: 5500: 5494: 5488: 5485: 5482: 5478: 5474: 5471: 5469: 5468:Shapiro delay 5466: 5464: 5461: 5458: 5454: 5450: 5447: 5444: 5440: 5437: 5436: 5433: 5430: 5427: 5424: 5422: 5419: 5417: 5414: 5412: 5411:collaboration 5408: 5404: 5401: 5399: 5395: 5392: 5391: 5388: 5385: 5383: 5380: 5378: 5377:Event horizon 5375: 5373: 5370: 5369: 5367: 5363: 5357: 5354: 5352: 5349: 5347: 5344: 5342: 5339: 5337: 5334: 5332: 5329: 5327: 5324: 5322: 5321:ADM formalism 5319: 5318: 5316: 5312: 5306: 5303: 5301: 5298: 5296: 5293: 5291: 5288: 5286: 5283: 5282: 5280: 5274: 5268: 5265: 5263: 5260: 5259: 5257: 5253: 5250: 5248: 5242: 5232: 5229: 5227: 5226:Biquaternions 5224: 5222: 5219: 5217: 5214: 5212: 5209: 5208: 5206: 5204: 5200: 5194: 5191: 5189: 5186: 5184: 5181: 5179: 5176: 5174: 5171: 5169: 5166: 5164: 5161: 5159: 5156: 5154: 5153:Time dilation 5151: 5150: 5148: 5144: 5138: 5135: 5134: 5132: 5128: 5122: 5119: 5117: 5114: 5112: 5109: 5107: 5106:Proper length 5104: 5102: 5099: 5097: 5094: 5092: 5089: 5087: 5084: 5082: 5079: 5078: 5076: 5070: 5064: 5061: 5059: 5056: 5053: 5050: 5048: 5044: 5041: 5040: 5038: 5034: 5031: 5029: 5023: 5019: 5012: 5007: 5005: 5000: 4998: 4993: 4992: 4989: 4983: 4979: 4976:group at the 4975: 4971: 4968: 4966: 4962: 4959: 4958: 4957: 4956: 4954: 4945: 4941: 4926: 4886: 4873: 4872: 4866: 4863: 4859: 4854: 4849: 4844: 4839: 4835: 4831: 4826: 4825:gr-qc/0510072 4821: 4817: 4813: 4809: 4805: 4802: 4800:0-19-286170-0 4796: 4792: 4788: 4784: 4781: 4779:0-7167-6034-7 4775: 4771: 4767: 4763: 4754:on 2011-08-28 4753: 4749: 4745: 4744: 4739: 4735: 4731: 4728: 4726:0-393-31276-3 4722: 4718: 4714: 4710: 4707: 4705:0-8176-3392-8 4701: 4697: 4693: 4692:Stachel, John 4689: 4686: 4682: 4678: 4674: 4670: 4669:2027.42/62586 4666: 4662: 4658: 4654: 4650: 4645: 4640: 4636: 4632: 4625: 4620: 4617: 4611: 4607: 4603: 4599: 4595: 4591: 4586: 4581: 4575: 4572: 4570:0-465-07835-4 4566: 4562: 4561: 4556: 4552: 4549: 4547:0-521-45506-5 4543: 4539: 4534: 4531: 4529:0-471-95853-0 4525: 4521: 4516: 4513: 4511:3-527-40571-2 4507: 4503: 4498: 4495: 4491: 4486: 4481: 4476: 4471: 4467: 4463: 4458: 4457:gr-qc/0306052 4453: 4449: 4445: 4440: 4431:on 2007-05-03 4430: 4426: 4422: 4421: 4416: 4411: 4408: 4406:0-679-45443-8 4402: 4398: 4397: 4392: 4388: 4385: 4383:0-19-853907-X 4379: 4375: 4374: 4369: 4368:Pais, Abraham 4365: 4362:on 2007-06-29 4358: 4354: 4350: 4346: 4342: 4338: 4334: 4329: 4328:gr-qc/0702017 4324: 4320: 4316: 4309: 4304: 4295:on 2012-12-06 4294: 4290: 4289: 4283: 4274: 4270: 4266: 4262: 4258: 4254: 4247: 4242: 4233:on 2011-06-10 4232: 4228: 4224: 4220: 4216: 4212: 4208: 4204: 4200: 4196: 4191: 4188: 4186:0-691-12201-6 4182: 4177: 4176: 4170: 4166: 4163: 4161:0-684-82292-X 4157: 4154:, Macmillan, 4153: 4152: 4147: 4143: 4134:on 2007-06-17 4133: 4129: 4125: 4120: 4117: 4113: 4109: 4103: 4099: 4095: 4091: 4087: 4082: 4081:gr-qc/0202055 4077: 4073: 4068: 4065: 4059: 4055: 4051: 4046: 4041: 4037: 4032: 4029: 4025: 4021: 4017: 4013: 4009: 4004: 3999: 3995: 3990: 3987: 3985:3-527-40574-7 3981: 3977: 3972: 3963:on 2017-07-13 3959: 3955: 3951: 3947: 3943: 3939: 3935: 3932:(S1): 58–85, 3931: 3927: 3920: 3915: 3912: 3910:0-387-98385-6 3906: 3901: 3900: 3893: 3890: 3888:3-527-40574-7 3884: 3880: 3875: 3863: 3862: 3856: 3853: 3851:0-375-41288-3 3847: 3843: 3839: 3835: 3834: 3829: 3828:Greene, Brian 3825: 3822: 3820:0-375-70811-1 3816: 3811: 3810: 3804: 3803:Greene, Brian 3800: 3797: 3793: 3789: 3785: 3780: 3775: 3771: 3767: 3763: 3759: 3754: 3751: 3749:0-19-856746-4 3745: 3741: 3736: 3733: 3731:0-226-28864-1 3727: 3723: 3718: 3715: 3711: 3707: 3703: 3699: 3695: 3690: 3689:gr-qc/0508016 3685: 3681: 3677: 3672: 3668: 3667: 3662: 3658: 3654: 3650: 3646: 3643: 3639: 3634: 3629: 3625: 3621: 3617: 3613: 3609: 3605: 3601: 3596: 3593: 3589: 3585: 3581: 3577: 3573: 3568: 3565: 3561: 3557: 3553: 3549: 3545: 3540: 3531:on 2011-04-14 3530: 3526: 3522: 3521: 3516: 3511: 3508: 3504: 3500: 3496: 3495:Physics World 3492: 3491:"Dark Energy" 3487: 3484: 3482:0-7382-0137-5 3478: 3474: 3473: 3468: 3464: 3461: 3459:3-527-40574-7 3455: 3451: 3447: 3443: 3440: 3438:0-85274-037-9 3434: 3430: 3425: 3422: 3416: 3412: 3407: 3398:on 2007-07-04 3397: 3393: 3389: 3384: 3379: 3374: 3369: 3365: 3361: 3357: 3353: 3349: 3344: 3341: 3337: 3332: 3327: 3323: 3319: 3315: 3311: 3307: 3303: 3302:Physics Today 3296: 3291: 3290: 3285: 3278: 3272: 3269: 3265: 3259: 3256: 3252: 3246: 3243: 3240: 3239:Caldwell 2004 3236: 3230: 3227: 3223: 3219: 3213: 3210: 3206: 3202: 3196: 3193: 3189: 3188:Caldwell 2004 3185: 3181: 3180:Einstein 1917 3175: 3172: 3168: 3164: 3160: 3154: 3151: 3147: 3143: 3137: 3134: 3130: 3126: 3122: 3116: 3113: 3109: 3105: 3101: 3095: 3092: 3088: 3084: 3078: 3075: 3071: 3067: 3062: 3059: 3055: 3051: 3047: 3043: 3039: 3035: 3031: 3027: 3022: 3017: 3014:(6): 061102, 3013: 3009: 3002: 2999: 2995: 2991: 2985: 2982: 2978: 2972: 2969: 2965: 2961: 2955: 2952: 2948: 2944: 2938: 2935: 2931: 2926: 2923: 2910: 2909: 2901: 2898: 2894: 2889: 2886: 2882: 2878: 2874: 2868: 2865: 2861: 2860:Bertotti 2005 2857: 2853: 2849: 2845: 2839: 2836: 2832: 2828: 2824: 2818: 2815: 2811: 2807: 2801: 2798: 2794: 2790: 2786: 2780: 2777: 2773: 2767: 2764: 2760: 2754: 2751: 2747: 2741: 2738: 2734: 2727: 2724: 2720: 2714: 2711: 2707: 2701: 2698: 2694: 2688: 2685: 2681: 2675: 2672: 2668: 2662: 2659: 2655: 2651: 2647: 2643: 2639: 2635: 2630: 2629:gr-qc/9806123 2625: 2621: 2617: 2610: 2607: 2603: 2599: 2595: 2591: 2585: 2582: 2578: 2574: 2568: 2565: 2561: 2555: 2552: 2548: 2544: 2538: 2535: 2531: 2525: 2522: 2518: 2517:Harrison 2002 2514: 2513:Doppler shift 2507: 2504: 2500: 2496: 2490: 2487: 2480: 2477: 2473: 2469: 2465: 2461: 2455: 2452: 2448: 2442: 2439: 2435: 2429: 2426: 2422: 2418: 2414: 2410: 2406: 2400: 2397: 2391: 2386: 2383: 2381: 2378: 2376: 2373: 2371: 2368: 2366: 2363: 2361: 2358: 2356: 2353: 2351: 2348: 2347: 2342: 2340: 2336: 2334: 2330: 2326: 2322: 2318: 2313: 2311: 2306: 2302: 2298: 2294: 2290: 2289:string theory 2286: 2282: 2278: 2274: 2270: 2265: 2258: 2256: 2254: 2250: 2245: 2241: 2236: 2234: 2230: 2227: 2223: 2219: 2215: 2211: 2207: 2203: 2199: 2195: 2190: 2182: 2178: 2173: 2166: 2164: 2162: 2156: 2154: 2153:that of light 2150: 2146: 2142: 2138: 2134: 2129: 2127: 2123: 2119: 2115: 2111: 2107: 2103: 2099: 2095: 2088: 2083: 2076: 2074: 2072: 2068: 2064: 2060: 2056: 2051: 2049: 2045: 2044:Joseph Taylor 2041: 2040:Russell Hulse 2036: 2033: 2029: 2025: 2021: 2020:binary pulsar 2016: 2011: 2009: 2005: 2001: 1996: 1994: 1990: 1989:gravity waves 1986: 1979: 1977: 1975: 1971: 1967: 1963: 1961: 1957: 1952: 1948: 1940: 1939:Huchra's lens 1936: 1932: 1928: 1923: 1916: 1914: 1912: 1904: 1902: 1900: 1896: 1891: 1889: 1885: 1884:atomic clocks 1881: 1877: 1873: 1869: 1864: 1862: 1858: 1857:neutron stars 1854: 1848: 1846: 1842: 1838: 1834: 1830: 1826: 1822: 1818: 1813: 1811: 1802: 1798: 1794: 1793:atomic clocks 1790: 1786: 1783: 1779: 1775: 1772: 1769: 1765: 1761: 1757: 1753: 1752:solar eclipse 1749: 1745: 1741: 1737: 1734: 1730: 1726: 1722: 1718: 1714: 1711:should be an 1710: 1706: 1702: 1698: 1697: 1692: 1688: 1685: 1681: 1673: 1671: 1669: 1665: 1661: 1657: 1656:Kerr solution 1653: 1649: 1645: 1641: 1637: 1633: 1629: 1625: 1620: 1618: 1614: 1610: 1606: 1602: 1598: 1579: 1567: 1563: 1558: 1555: 1552: 1546: 1534: 1533: 1532: 1530: 1526: 1522: 1518: 1515: 1511: 1507: 1502: 1500: 1496: 1487: 1483: 1481: 1477: 1472: 1463: 1461: 1457: 1453: 1449: 1448:four-momentum 1445: 1440: 1438: 1434: 1430: 1426: 1422: 1421: 1418: =  1417: 1412: 1407: 1405: 1401: 1397: 1389: 1387: 1384: 1379: 1375: 1369: 1367: 1361: 1359: 1355: 1351: 1347: 1343: 1338: 1336: 1332: 1328: 1327:non-Euclidean 1324: 1320: 1316: 1307: 1300: 1298: 1296: 1292: 1288: 1285:Paraphrasing 1280: 1278: 1276: 1272: 1268: 1263: 1261: 1256: 1252: 1248: 1243: 1241: 1237: 1234: 1230: 1226: 1222: 1218: 1214: 1210: 1206: 1202: 1198: 1194: 1189: 1187: 1183: 1179: 1178: 1172: 1170: 1166: 1162: 1158: 1154: 1146: 1144: 1140: 1138: 1134: 1130: 1126: 1120: 1117: 1107: 1101:Tidal effects 1100: 1098: 1096: 1091: 1089: 1083: 1081: 1076: 1074: 1070: 1066: 1062: 1058: 1053: 1044: 1040: 1033: 1031: 1029: 1024: 1019: 1017: 1008: 1004: 1001: 1000: 999: 997: 993: 984: 977: 975: 973: 967: 965: 961: 957: 953: 947: 939: 937: 935: 929: 927: 923: 919: 915: 911: 907: 903: 895: 893: 891: 887: 881: 879: 875: 871: 867: 863: 859: 855: 850: 848: 844: 840: 836: 832: 828: 824: 819: 816: 811: 809: 805: 802:developed by 801: 797: 793: 782: 777: 775: 770: 768: 763: 762: 760: 759: 753: 743: 740: 735: 729: 728: 727: 726: 719: 718: 714: 712: 709: 707: 704: 702: 699: 697: 694: 692: 689: 687: 684: 682: 679: 677: 674: 672: 669: 667: 664: 662: 659: 657: 656:Chandrasekhar 654: 652: 649: 647: 644: 642: 639: 637: 634: 632: 629: 627: 624: 622: 619: 617: 614: 612: 609: 607: 604: 602: 599: 597: 594: 592: 589: 587: 584: 582: 579: 577: 574: 572: 571:Schwarzschild 569: 567: 564: 562: 559: 557: 554: 552: 549: 548: 540: 539: 532: 531:Hartle–Thorne 529: 527: 524: 522: 519: 517: 514: 512: 509: 507: 504: 502: 499: 497: 494: 492: 489: 487: 484: 482: 479: 477: 474: 472: 469: 467: 464: 462: 459: 457: 454: 452: 449: 446: 442: 441:Schwarzschild 439: 438: 434: 428: 427: 416: 413: 411: 408: 407: 406: 405: 400: 395: 392: 390: 387: 385: 382: 381: 380: 379: 374: 369: 366: 364: 361: 359: 356: 354: 351: 349: 346: 344: 341: 340: 339: 338: 333: 323: 320: 319: 314: 313: 302: 299: 297: 294: 292: 289: 288: 287: 286: 283: 279: 274: 271: 269: 266: 264: 263:Event horizon 261: 259: 256: 254: 251: 249: 246: 244: 241: 239: 236: 234: 231: 229: 226: 225: 224: 223: 213: 212: 205: 202: 200: 197: 195: 192: 190: 187: 186: 178: 177: 172: 169: 164: 161: 159: 156: 154: 151: 150: 148: 146: 143: 142: 141: 140: 122: 119: 115: 110: 106: 101: 98: 94: 87: 82: 79: 75: 65: 61: 60: 57: 53: 47: 43: 39: 35: 34: 28: 22: 6076: 6059:Solar System 5926: 5922:gauge theory 5816: 5510:Kaluza–Klein 5262:Introduction 5261: 5188:Twin paradox 4950: 4949: 4876:, retrieved 4870: 4815: 4811: 4790: 4769: 4756:, retrieved 4752:the original 4741: 4716: 4695: 4634: 4630: 4597: 4584: 4559: 4537: 4519: 4501: 4447: 4443: 4433:, retrieved 4429:the original 4418: 4395: 4372: 4357:the original 4321:(6): 30–34, 4318: 4314: 4297:, retrieved 4293:the original 4287: 4276:, retrieved 4256: 4252: 4235:, retrieved 4231:the original 4205:(2): 30–37, 4202: 4198: 4174: 4150: 4146:Maddox, John 4136:, retrieved 4132:the original 4127: 4071: 4035: 3993: 3975: 3965:, retrieved 3958:the original 3929: 3925: 3903:, Springer, 3898: 3878: 3868:, retrieved 3860: 3832: 3808: 3761: 3757: 3739: 3721: 3679: 3675: 3665: 3652: 3607: 3603: 3578:(6): 52–57, 3575: 3571: 3547: 3544:Science News 3543: 3533:, retrieved 3529:the original 3518: 3501:(5): 37–42, 3498: 3494: 3471: 3467:Blair, David 3449: 3428: 3410: 3400:, retrieved 3396:the original 3355: 3351: 3308:(5): 41–47, 3305: 3301: 3286:Bibliography 3271: 3258: 3245: 3235:Milgrom 2002 3229: 3212: 3205:Penrose 2004 3195: 3174: 3153: 3136: 3115: 3094: 3077: 3072:, pp. 70–86. 3061: 3011: 3007: 3001: 2994:Lochner 2007 2990:Newbury 1997 2984: 2971: 2954: 2937: 2925: 2915:, retrieved 2907: 2900: 2888: 2867: 2838: 2817: 2800: 2785:Wheeler 1990 2779: 2772:Penrose 2004 2766: 2759:Wheeler 1990 2753: 2746:Giulini 2005 2740: 2733:Poisson 2004 2726: 2719:Wheeler 1990 2713: 2700: 2693:Wheeler 1990 2687: 2674: 2667:Wheeler 1990 2661: 2619: 2615: 2609: 2602:Wheeler 1990 2584: 2573:Wheeler 1990 2567: 2560:Wheeler 1990 2554: 2537: 2524: 2506: 2489: 2479: 2472:Stachel 1989 2460:Janssen 2005 2454: 2441: 2434:Wheeler 1990 2428: 2413:Janssen 2005 2399: 2337: 2314: 2304: 2266: 2262: 2249:accelerating 2237: 2235:ever since. 2186: 2157: 2130: 2091: 2052: 2037: 2028:neutron star 2012: 1997: 1983: 1964: 1944: 1911:astrophysics 1908: 1892: 1870:such as the 1865: 1849: 1814: 1806: 1684:Solar System 1677: 1631: 1627: 1623: 1621: 1612: 1604: 1600: 1596: 1594: 1528: 1520: 1516: 1503: 1492: 1469: 1441: 1419: 1415: 1408: 1393: 1382: 1370: 1362: 1352:, such as a 1350:great circle 1339: 1312: 1290: 1287:John Wheeler 1284: 1264: 1259: 1244: 1190: 1175: 1173: 1150: 1141: 1137:tidal effect 1121: 1112: 1092: 1084: 1077: 1069:blue-shifted 1049: 1037: 1020: 1016:next section 1012: 991: 989: 968: 952:free-falling 949: 930: 899: 882: 870:microquasars 854:astrophysics 851: 820: 812: 791: 790: 716: 676:Raychaudhuri 145:Introduction 144: 31: 6047:Outer space 6035:Spaceflight 5999:Mathematics 5953:Mathematics 5599:Kerr–Newman 5570:Spherical: 5439:Other tests 5382:Singularity 5314:Formulation 5276:Fundamental 5130:Formulation 5111:Proper time 5072:Fundamental 4713:Thorne, Kip 4555:Smolin, Lee 3813:, Vintage, 3475:, Perseus, 3413:, Berkley, 3264:Lehner 2002 3222:Smolin 2001 3218:Greene 1999 3201:Maddox 1998 3159:Wright 2007 3146:Thorne 1994 3129:Robson 1996 3125:Disney 1998 3108:Gnedin 2005 3100:Thorne 1994 3066:Schutz 2003 2977:Schutz 2003 2930:Kramer 2004 2793:Schutz 2003 2789:Thorne 1994 2706:Geroch 1978 2598:Mermin 2005 2594:Greene 2004 2590:Thorne 1994 2547:Pössel 2007 2530:Mermin 2005 2447:Norton 1985 2417:Schutz 2003 2325:dark matter 2321:dark energy 2253:dark energy 2244:empty space 2194:homogeneous 2104:of massive 2077:Black holes 1974:dark matter 1880:timekeeping 1876:positioning 1782:white dwarf 1744:arc seconds 1674:Experiments 1425:temperature 1323:world lines 1233:dimensional 1215:. In 1907, 1057:red-shifted 996:accelerated 858:black holes 800:gravitation 691:van Stockum 621:Oppenheimer 476:Kerr–Newman 268:Singularity 6083:Categories 5751:Zel'dovich 5659:Scientists 5638:Alcubierre 5445:of Mercury 5443:precession 5372:Black hole 5255:Background 5247:relativity 5216:World line 5211:Light cone 5036:Background 5028:relativity 5018:Relativity 4940:Audio help 4931:2021-05-09 4878:2007-06-12 4758:2007-06-13 4435:2007-05-06 4299:2007-06-12 4278:2007-06-11 4237:2007-06-13 4138:2007-06-12 3967:2013-07-15 3870:2007-05-06 3535:2007-07-15 3402:2007-07-06 3184:Cowen 2001 3167:Berry 1989 3163:Hogan 1999 3021:1602.03837 2947:Ashby 2003 2943:Ashby 2002 2917:2009-05-02 2844:Hartl 2005 2464:Ernst Mach 2392:References 2287:, notably 2098:black hole 2024:PSR1913+16 2008:black hole 1825:gyroscopes 1652:black hole 1182:equivalent 829:and other 544:Scientists 376:Formalisms 324:Formalisms 273:Black hole 199:World line 6011:Astronomy 5886:evolution 5721:Robertson 5706:Friedmann 5701:Eddington 5691:de Sitter 5525:Solutions 5403:detectors 5398:astronomy 5365:Phenomena 5300:Geodesics 5203:Spacetime 5146:Phenomena 4587:: 161–172 4563:, Basic, 4353:118949889 4028:119203172 4003:0709.0685 3642:118162303 3054:124959784 2964:Will 2006 2960:Will 1993 2893:Pais 1982 2877:Will 1993 2831:Will 2006 2827:Will 1993 2680:Pais 1982 2577:Pais 1982 2495:Pais 1982 2423:, p. 178. 2421:Pais 1982 2411:, and in 2409:Pais 1982 2405:Renn 2005 2317:cosmology 2273:classical 2233:expanding 2198:isotropic 2181:radiation 2167:Cosmology 2137:radiation 2102:evolution 1740:deflected 1640:spacetime 1556:π 1499:longitude 1437:molecules 1335:geodesics 1319:spacetime 1236:spacetime 1205:triangles 1177:curvature 1129:skydivers 1065:frequency 878:cosmology 876:model of 862:radiation 808:spacetime 636:Robertson 601:Friedmann 596:Eddington 586:Nordström 576:de Sitter 433:Solutions 358:Geodesics 353:Friedmann 335:Equations 321:Equations 282:Spacetime 217:Phenomena 123:ν 120:μ 111:κ 102:ν 99:μ 91:Λ 83:ν 80:μ 42:spacetime 5939:M-theory 5891:genetics 5834:Category 5711:LemaĂźtre 5676:Einstein 5666:PoincarĂ© 5626:Others: 5610:Taub–NUT 5576:interior 5498:theories 5496:Advanced 5463:redshift 5278:concepts 5096:Rapidity 5074:concepts 4942: Â· 4862:28179873 4818:(1): 3, 4789:(1993), 4768:(1990), 4715:(1994), 4677:15931216 4557:(2001), 4494:28179866 4450:(1): 6, 4393:(2004), 4370:(1982), 4227:12140952 4171:(2005), 4148:(1998), 3954:10641693 3830:(2004), 3805:(1999), 3788:15931201 3714:37236624 3663:(1961), 3392:28163638 3358:(1): 1, 3340:28163638 3046:26918975 2654:12502462 2343:See also 2222:Big Bang 2214:nuclear- 2189:universe 2126:galaxies 2118:billions 2114:millions 2071:Big Bang 2067:universe 2010:merger. 1785:Sirius B 1495:latitude 1452:pressure 1444:momentum 1376:towards 1213:surfaces 1157:surfaces 1153:geometry 992:produced 874:Big Bang 752:Category 616:LemaĂźtre 581:Reissner 566:PoincarĂ© 551:Einstein 496:Taub–NUT 461:Wormhole 445:interior 158:Timeline 48:'s mass. 6094:Gravity 6071:Science 5987:Physics 5973:Portals 5917:entropy 5905:Physics 5896:viruses 5879:Biology 5776:Hawking 5771:Penrose 5756:Novikov 5736:Wheeler 5681:Hilbert 5671:Lorentz 5628:pp-wave 5449:lensing 5245:General 5026:Special 4929: ( 4900:minutes 4853:5256066 4830:Bibcode 4685:4383030 4649:Bibcode 4602:Bibcode 4485:5256043 4462:Bibcode 4333:Bibcode 4261:Bibcode 4207:Bibcode 4116:9145148 4086:Bibcode 4008:Bibcode 3934:Bibcode 3838:Bibcode 3796:3023436 3766:Bibcode 3694:Bibcode 3612:Bibcode 3580:Bibcode 3564:3981642 3383:5253894 3360:Bibcode 3331:5253894 3310:Bibcode 3144:and in 3085:and in 3026:Bibcode 2634:Bibcode 2600:and in 2226:billion 2141:quasars 2094:compact 2022:called 2006:from a 1821:Cassini 1764:quasars 1729:Mercury 1721:Mercury 1713:ellipse 1615:is the 1607:is the 1456:tension 1427:or the 1358:equator 1356:or the 1346:segment 1342:geodesy 926:gravity 831:planets 827:Mercury 671:Hawking 666:Penrose 641:Bardeen 631:Wheeler 561:Hilbert 556:Lorentz 516:pp-wave 153:History 38:delayed 33:Cassini 5817:others 5806:Thorne 5796:Misner 5781:Taylor 5766:Geroch 5761:Ehlers 5731:Zwicky 5549:Kasner 4860:  4850:  4797:  4776:  4723:  4702:  4683:  4675:  4631:Nature 4612:  4567:  4544:  4526:  4508:  4492:  4482:  4403:  4380:  4351:  4225:  4183:  4158:  4114:  4104:  4060:  4026:  3982:  3952:  3907:  3885:  3848:  3817:  3794:  3786:  3758:Nature 3746:  3728:  3712:  3640:  3562:  3479:  3456:  3435:  3417:  3390:  3380:  3338:  3328:  3052:  3044:  2850:, and 2652:  2592:, and 2458:E. g. 2206:matter 2133:energy 1951:galaxy 1947:quasar 1931:quasar 1861:pulsar 1748:degree 1705:planet 1480:metric 1433:nuclei 1411:energy 1331:curved 1267:matter 1197:points 994:by an 823:orbits 796:theory 750:  717:others 711:Thorne 701:Newman 681:Taylor 661:Ehlers 646:Walker 611:Zwicky 486:Kasner 6023:Stars 5811:Weiss 5791:Bondi 5786:Hulse 5716:Milne 5620:discs 5564:Milne 5559:Gödel 5416:Virgo 4820:arXiv 4681:S2CID 4639:arXiv 4627:(PDF) 4452:arXiv 4360:(PDF) 4349:S2CID 4323:arXiv 4311:(PDF) 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Index

General relativity

Cassini
delayed
spacetime
Sun
General relativity
Spacetime curvature schematic
Introduction
History
Timeline
Tests
Mathematical formulation
Equivalence principle
Special relativity
World line
Pseudo-Riemannian manifold
Kepler problem
Gravitational lensing
Gravitational redshift
Gravitational time dilation
Gravitational waves
Frame-dragging
Geodetic effect
Event horizon
Singularity
Black hole
Spacetime
Spacetime diagrams
Minkowski spacetime

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