Gauge approach to gravitation, physical spacetime and gravitational interaction

The physical significance and comparative characteristics of the Poincare gauge theory of gravity - the gravitation theory in 4-dimensional Riemann-Cartan spacetime - is discussed. It is shown that isotropic cosmology built in the framework of the Poincare gauge theory of gravity by using sufficiently general expression of gravitational Lagrangian leads to the solution of the problem of cosmological singularity, and allows also to explain the accelerating cosmological expansion at present epoch without using the notion of dark energy. The conclusion that spacetime torsion plays the principal role by the change of gravitational interaction by certain physical conditions in comparison with general relativity theory is obtained.