The geometrical meaning of time - the emergence of the concept of time in the general theory of relativity
Pp. 153-165 (13)
It is stated in many text books that the any metric appearing in general relativity
should be locally Lorentzian i.e. of the type ημv = diag (1,−1,−1,−1)
this is usually presented as an independent axiom of the theory, which can
not be deduced from other assumptions. In this work we show that the
above assertion is a consequence of a standard linear stability analysis of the
Einstein equations and need not be assumed.
Ariel University Center of Samaria, Ariel 40700, Israel.