and Y. Z. Zhang. This work is supported in part by Innotec Design, Inc., U.S.A.
ENDNOTES
1) In general relativity, Einstein [2,3] considers the four-dimensional space-time reality as a physical space-time modeled as a Riemannian space-time (M, g). The Riemannian space M is characterized by a space-time metric gik that can be determined by physical considerations such as the distribution of matter. In ?elativity and the problem of space", Einstein [27] wrote,
?or the functions gik describe not only the field, but at the same time also the topological and metrical structural properties of the manifold. ... There is no such thing as an empty space, i.e., a space without field. Space-time does not claim existence on its own, but only as a structural quality of the field."
Moreover, since such a Riemannian space-time models reality, all the physical requirements must be sufficiently satisfied.
2) A local Minkowskian space is a short hand to express that special relativity is locally valid, except for phenomena involving the space-time curvature.
3) For example, the Wheeler-Hawking School [13,18,40] follows Pauli? misinterpretation, and thus, their theories are different from general relativity. They, different from Einstein [2,3], believe that space-time coordinates have no physical meaning. Hawking [18] makes no secret of his disagreements with Einstein [2,3]. More recently, based on misinterpretations of Fock [39], Ohanian, Ruffini, and Wheeler [22] openly criticized Einstein? theory as confusing and his principles invalid.
4) Some theorists believe that the solution of gravity for a weak source need not be bounded [38]. However, it has been shown that the equivalent principle implies compatibility with Einstein? notion of weak gravity [46].


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