Changes

The advance (or precession<ref>A "precession" is a slow gyration of an axis of rotation such that it traces a cone.</ref>) of the perihelion of Mercury is observed but not predicted by an elementary application of Newtonian mechanics to Mercury and the sun alone.  This provided one of the great mysteries of physics around the turn of the century.  A planet's "perihelion" is the point in its path of orbit that comes closest to the sun.  For Mercury, that point of closest proximity is shifting with each revolution.

The advance (or precession<ref>A "precession" is a slow gyration of an axis of rotation such that it traces a cone.</ref>) of the perihelion of Mercury is observed but not predicted by an elementary application of Newtonian mechanics to Mercury and the sun alone.  This provided one of the great mysteries of physics around the turn of the century.  A planet's "perihelion" is the point in its path of orbit that comes closest to the sun.  For Mercury, that point of closest proximity is shifting with each revolution.

The [[theory of relativity]] developed to explain the then-observed shift in Mercury's perihelion of 42.98 (±0.04) arc-seconds per century.  At the time, that provided a fit to the observed data.  Subsequently, however, more accurate measurements with more sophisticated technology have determined a precise value of this precession (5599.7 arc-seconds per century), and the number provided by relativity no longer fits the data within a margin of error.  Professor Clifford Will, a leading advocate for [[General Relativity]] omits this issue entirely from his paper summarizing experimental evidence for relativity.<ref>[http://www.ias.ac.in/pramana/v63/p731/fulltext.pdf The confrontation between general relativity

The [[theory of relativity]] developed to explain the then-observed shift in Mercury's perihelion of 42.98 (±0.04) arc-seconds per century.  At the time, that provided a fit to the observed data.  Subsequently, however, more accurate measurements with more sophisticated technology have determined a precise value of this precession (5599.7 arc-seconds per century), and the number provided by relativity no longer fits the data within a margin of error.  Professor Clifford Will, a leading advocate for [[General Relativity]], omits this test entirely from his paper summarizing experimental evidence for relativity.<ref>[http://www.ias.ac.in/pramana/v63/p731/fulltext.pdf The confrontation between general relativity

and experiment]</ref>

and experiment]</ref>