Time&Eternity

146 chapter 3
speak only of space-time? Does Einstein himself draw such a conclusion? In
his presentation of the general theory of relativity, after initial skepticism,
Einstein expresses 165 his admiration for Minkowski’s interpretation of the
special theory of relativity: “The generalization of the theory of relativity
has been greatly facilitated by the form that was given to the special theory
of relativity by Minkowski, the mathematician who first clearly recognized
the formal equivalency of the spatial and time coordinates and used it for
establishing the theory.” 166 Without Minkowski, the general theory of relativity
would have “perhaps remained stuck in infancy.” 167
Elsewhere, however, Einstein expressed himself much more cautiously:
From a formal point of view one may characterize the achievement of the special
theory of relativity thus: it has shown generally the role which the universal constant
c (velocity of light) plays in the laws of nature and has demonstrated that there
exists a close connection between the form in which time on the one hand and the
spatial coordinates on the other hand enter into the laws of nature. 168
He therefore appears to presuppose a difference between space and time
despite their arithmetical unification as coordinates of one and the same
system. Or is this more an emotional assertion of an elderly man rather
than of a scientist? For in “A London Speech,” Einstein says when referring
to Minkowski: “According to the special theory of relativity the four dimensional
continuum formed by the union of space and time retains the absolute
character which, according to the earlier theory, belonged to both
space and time separately.” 169 Mathematically, “no statement is more banal
than that our familiar world is a four-dimensional time-space continuum,”
170 for it can be shown that the laws of nature, which correspond to the
requirements of the theory of relativity, “assume mathematical forms in
which the time coordinate plays exactly the same role as the three spatial coordinates.”
171
How, then, can this loss of autonomy of time and space be understood?
172 Classical physics could allow itself two equally valid interpretations
of a space-time continuum, namely, first as a dynamic concept of positions
that change in time, and, second, as a static concept of movement as
something existing. In the first case, the continuum is broken down into
space and time; in the second, it is viewed as a whole. In classical physics,
the oscillation between the two concepts presents no problem inasmuch as,
according to the idea of absolute time, the time coordinate always remains
the same. When relating to another system, only the space coordinates, but
not the time coordinates, are transformed. Within the special theory of relativity,
on the other hand, a space-time continuum cannot simply be split
into a space and a time dimension, since in two different systems, not only