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General Relativity, like [[Quantum Mechanics]] (the other of the two theories comprising "modern physics") both hav reputations for being notoriously complicated and difficult to understand.  In fact, in the early decades of the 20^th century, General Relativity had a sort of cult status in this regard.  General Relativity and Quantum Mechanics are both advanced college-level and postgraduate level topics.  Conservapedia can't really explain either of them fully.  But, in the article below, we will attempt to give a rough outline of the General Relativistic formulation of gravity.

General Relativity, like [[Quantum Mechanics]] (the other of the two theories comprising "modern physics") both hav reputations for being notoriously complicated and difficult to understand.  In fact, in the early decades of the 20^th century, General Relativity had a sort of cult status in this regard.  General Relativity and Quantum Mechanics are both advanced college-level and postgraduate level topics.  Conservapedia can't really explain either of them fully.  But, in the article below, we will attempt to give a rough outline of the General Relativistic formulation of gravity.

The general theory of relativity is a ''metric theory,'' sometimes also called a ''geometric theory.'' Metric theories describe physical phenomena in terms of [[differential geometry]]. This stands in contrast to Isaac Newton's [[Law of Universal Gravitation|law of universal gravitation]], which described gravity in terms of a [[vector field]].  In the case of general relativity, the theory relates ''stress-energy'' — an extension of the concept of [[mass]] — and the [[curvature]] of [[spacetime]]. In the words of physicist John Wheeler, "Space tells matter how to move, matter tells space how to curve."<ref>Misner, Thorne & Wheeler. ''Gravitation.'' (1973)</ref>

The general theory of relativity is a ''metric theory,'' sometimes also called a ''geometric theory.'' Metric theories describe physical phenomena in terms of [[differential geometry]]. This stands in contrast to Isaac Newton's [[Law of Universal Gravitation|law of universal gravitation]], which described gravity in terms of a [[vector field]].  In the case of general relativity, the theory relates ''stress-energy'' — an extension of the concept of [[mass]] — and the [[curvature]] of [[spacetime]]. In the words of physicist John Wheeler, "Space tells matter how to move, matter tells space how to curve."<ref>Misner, Thorne & Wheeler. ''Gravitation.'' (1973)</ref>

The theory was inspired by a thought experiment developed by Einstein involving two elevators.  The first elevator is stationary on the Earth, while the other is being pulled through space at a constant acceleration of g.  Einstein realized that any physical experiment carried out in the elevators would give the same result.  This realization is known as the equivalence principle and it states that accelerating frames of reference and gravitational fields are indistinguishable.  General Relativity is the theory of gravity that incorporates Special Relativity and the equivalence principle.

The theory was inspired by a thought experiment developed by Einstein involving two elevators.  The first elevator is stationary on the Earth, while the other is being pulled through space at a constant acceleration of g.  Einstein realized that any physical experiment carried out in the elevators would give the same result.  This realization is known as the equivalence principle and it states that accelerating frames of reference and gravitational fields are indistinguishable.  General Relativity is the theory of gravity that incorporates Special Relativity and the equivalence principle.

==Qualitative Introduction to General Relativity==

==Qualitative Introduction to General Relativity==