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===Gravitational Lensing===

===Gravitational Lensing===

General relativity predicts that the path of light will be distorted when it passes near a massive object.  In 1919, Sir [[Arthur Eddington]], an esteemed English astronomer, used this to test general relativity by observing the bending of starlight around the sun during a total [[solar eclipse]].<ref>Paul Johnson, British historian</ref>.  (A smaller degree of bending could also be consistent with Newton's theory, if one hypothesized light to consist of particles.  However, that [[particle theory of light]] had gone out of favor previously.)  Eddington detected a bending of light, but his range of error overlapped both Einstein's and Newton's predictions.  Upon his return to England, Eddington declared that his observations proven the theory of relativity.  His experiment was later confirmed by more rigorous experiments, such as those performed by the [[Hubble Space Telescope]] <ref>[http://www.spaceimages.com/gravlen.html Hubble Gravitational Lens Photo]</ref><ref> [http://csep10.phys.utk.edu/astr162/lect/galaxies/lensing.html Gravitational Lensing] </ref><ref>[http://www.iam.ubc.ca/~newbury/lenses/glgallery.html]</ref>.  Lorentz has this to say on the discrepancies between the empirical eclipse data and Einstein's predictions.

General relativity predicts that the path of light will be distorted when it passes near a massive object.  In 1919, Sir [[Arthur Eddington]], an esteemed English astronomer, used this to test general relativity by observing the bending of starlight around the sun during a total [[solar eclipse]].<ref>Paul Johnson, British historian</ref>.  (A smaller degree of bending could also be consistent with Newton's theory, if one hypothesized light to consist of particles.  However, that [[particle theory of light]] had gone out of favor previously.)  Eddington detected a bending of light, but his range of error overlapped both Einstein's and Newton's predictions.  Upon his return to England, Eddington declared that his observations proven the theory of relativity.  His experiment was later confirmed by more rigorous experiments, such as those performed by the [[Hubble Space Telescope]] <ref>[http://www.spaceimages.com/gravlen.html Hubble Gravitational Lens Photo]</ref><ref> [http://csep10.phys.utk.edu/astr162/lect/galaxies/lensing.html Gravitational Lensing] </ref><ref>[http://www.iam.ubc.ca/~newbury/lenses/glgallery.html]</ref>.  Lorentz has this to say on the discrepancies between the empirical eclipse data and Einstein's predictions.