Page:The Meaning of Relativity - Albert Einstein (1922).djvu/125

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Although all of these effects are inaccessible to experiment, because $$\kappa$$ is so small, nevertheless they certainly exist according to the general theory of relativity. We must see in them a strong support for Mach's ideas as to the relativity of all inertial actions. If we think these ideas consistently through to the end we must expect the whole inertia, that is, the whole $$g_{\mu\nu}$$-field, to be determined by the matter of the universe, and not mainly by the boundary conditions at infinity.

For a satisfactory conception of the $$g_{\mu\nu}$$-field of cosmical dimensions, the fact seems to be of significance that the relative velocity of the stars is small compared to the velocity of light. It follows from this that, with a


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