New and recent trends in modern cosmology

New and non-conventional theories in modern cosmology, for both Steady State and Big Bang, are discussed. The motivation behind these treatments is to solve some of the problems of the conventional cosmology. For this aim, different geometric structures and alternative field theories, used to construct world models, are given. A brief review of absolute parallelism (AP) geometry and its parameterized version (PAP), as a wider geometry than the Riemannian one, is presented. World models constructed using alternative field theories, constructed in the AP geometry, are discussed and compared. Some points regarding the use of ε(∞) topology in the field of cosmology are commented upon. A new path equation, admitted by the PAP geometry, is used to obtain, the effect of spin–gravity interaction on the cosmological parameters.