Most of mainstream science is based upon the thesis of physicalism, that all that exists are physical entities, that can be described without recourse to any non-physical entity. Thus, the origin of life, and the universe, as well as the end of he universe cannot make any valid recourse to God, a non-physical being outside of the system. Thus, there is the theory of biological evolution, and cosmological theories based upon the Big Bang – that matter and energy just existed in a tiny space, then exploded, and ultimately made everything, by chance.
As noted below, there are deep cracks in the physicalist world view, with a possible failure of its cosmological model coming up. But, it is a secular religion of the age, one of its cults being, for example, vaccine worship, so we cannot expect the paradigm to fall too soon. As I see it, this scientism underlies technocracy, which is based upon an unquestioned faith in science. History may chip away at this, ultimately exposing its bankruptcy.