: In fact physical theories in general explain how, but not why, things happen.

I couldn't agree more. As a matter of fact General Relativity is based in the equivalence principle. This principle states that a uniform gravitational field is equivalence to a uniformly accelerating frame of reference. This is equivalent to saying that gravitaitonal mass equal inertial mass. However is assumes this to be true. It is only confirmed by experiment. And only to certian limits. But so far so good.

It's a common misconception to say that Einstein explains gravity. On the contrary. AS Sir Arthur Eddington said The purpose of Einstein's new theory has often been misunderstood, and it has been criticised as an attempt to explain gravitation. The theory does not offer any explanation of gravitation; that lies quite outside its scope, and it does not even hint at a mechanism. It is true that we have introduced a definite hypothesis as to the relation between gravitation and space; but if that explains anything, it explains not gravitation, but space, i.e. the scaffolding constructed from our measures.

Chandrasehkar said the same thing with the equality of the inertial and gravitational mass.

If one were to read Einstein's work on the matter it's obvious that Einstein himself never claimed to explain gravity.

• Re: Mass and gravitational force - Zephram_Cochrane/">Zephram Cochrane - February 8, 2000 - 20:15 UTC
  • Re: Mass and gravitational force - pmb - February 8, 2000 - 22:35 UTC