Big Bang revisited
arXiv:2604.00077
Abstract
The Friedmann cosmological solution of the standard Einstein gravitational field equation has a curvature singularity at a moment in time known as the Big Bang. It has been suggested that this Big Bang curvature singularity can be eliminated by use of a degenerate spacetime metric. This proposal was the main topic of our talk at the Workshop, but, here, we also discuss the possible appearance of CPT-conjugated worlds and the conjectured relevance of an extended version of Einstein's field equation.
write-up of an invited talk at the "Workshop on Tensions in Cosmology" of the Corfu Summer Institute, September 2-8, 2025; v4: 27 pages and 7 figures, two references updated