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Another prediction of special relativity was time dilation in rapidly moving objects.  This has been verified in the anomalously slow decay of relativistic cosmic muons.  In fact, time dilation must be taken into account in all high-energy nuclear physics experiments.

Another prediction of special relativity was time dilation in rapidly moving objects.  This has been verified in the anomalously slow decay of relativistic cosmic muons.  In fact, time dilation must be taken into account in all high-energy nuclear physics experiments.

Predictions of general relativity turned out to be more obscure and difficult to test.  The two most famous predictions were the bending of light in a gravitational field and the precession of the perihelia of orbiting planets.  The first of these was famously tested during a total eclipse in 1919, but in fact the data were manipulated to try to fit the theory.  An objective review of the data was inconclusive.  Note that Newtonian mechanics also predicts the bending of light around massive objects.

Predictions of general relativity turned out to be more obscure and difficult to test.  The two most famous predictions were the bending of light in a gravitational field and the precession of the perihelia of orbiting planets.  The first of these was famously tested during a total eclipse in 1919.  That test was somewhat muddled by an incorrect initial calculation, by several people including Einstein himself, of what the effect would be, and some "cherry picking" of the data to be used <ref>''Einstein's Luck'', John Waller, Oxford University Press, ISBN 0-19-860719-9</ref>.  The data selection could be considered "manipulation" or "fudging", by a person (Arthur Eddington) who had a personal stake in the outcome.  His analysis techniques would not pass muster today.

 

It should be noted that pre-relativistic (Newtonian) physics also may predict a bending, of half the observed value, depending on whether one uses the 17^th century "corpuscular" formulation or the 19^th century wave formulation.

 

Nevertheless, it has been verified with ever-increasing precision in subsequent eclipses, and in the observations of quasar 3C273.

The second "classical" test of general relativity was the advance of the perihelion of the orbit of Mercury.  There are many complex effects contributing to this, including gravitational perturbations from other planets and effect of the oblateness of the Sun.  These are hard to calculate accurately, but, by 1900 it was known reasonably accurately that there was an "anomalous" precession, that is, a precession beyond all other known effects, of about 43 arc seconds per century.  This is a very tiny effect, but astronomical measurements were sufficiently accurate by that time to show it clearly.  At first relativists claimed that the precession is explained by general relativity, but more accurate measurements revealed that general relativity is disproved by the observations of the precession.  Newtonian mechanics can explain the precession if the exponent of the distance in the force equation is not precisely 2, or if the tug on Mercury from other planets in the solar system is taken into account.

The second "classical" test of general relativity was the advance of the perihelion of the orbit of Mercury.  There are many complex effects contributing to this, including gravitational perturbations from other planets and effect of the oblateness of the Sun.  These are hard to calculate accurately, but, by 1900 it was known reasonably accurately that there was an "anomalous" precession, that is, a precession beyond all other known effects, of about 43 arc seconds per century.  This is a very tiny effect, but astronomical measurements were sufficiently accurate by that time to show it clearly.  At first relativists claimed that the precession is explained by general relativity, but more accurate measurements revealed that general relativity is disproved by the observations of the precession.  Newtonian mechanics can explain the precession if the exponent of the distance in the force equation is not precisely 2, or if the tug on Mercury from other planets in the solar system is taken into account.

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==Predicted consequences of the Theories==

==Predicted consequences of the Theories==

===Time dilation===

===Time dilation===