Hh. Vonborzeszkowski et Hj. Treder, THE WEYL-CARTAN SPACE PROBLEM IN PURELY AFFINE THEORY, General relativity and gravitation, 29(4), 1997, pp. 455-466
According to Poincare, only the ''epistemological sum of geometry and
physics is measurable''. Of course, there are requirements of measurem
ent to be imposed on geometry because otherwise the theory resting on
this geometry cannot be physically interpreted. In particular, the Wey
l-Cartan space problem must be solved, i.e., it must be guaranteed tha
t the comparison of distances is compatible with the Levi-Civita trans
port. In the present paper, we discuss these requirements of measureme
nt and show that in the (purely affine) Einstein-Schrodinger unified f
ield theory the solution of the Weyl-Cartan space problem simultaneous
ly determines the matter via Einstein's equations. Here the affine fie
ld Gamma(kl)(i) represents Poincare's sum, and the solution of the spa
ce problem means its splitting in a metrical space and in matter field
s, where the latter are given by the torsion tensor Gamma([kl])(i).