  Subject of this article is the relationship between modern cosmology and
fundamental physics, in particular general relativity as a theory of gravity on
one side, together with its unique application in cosmology, and the formation
of structures and their statistics on the other. It summarises arguments for
the formulation for a metric theory of gravity and the uniqueness of the
construction of general relativity. It discusses symmetry arguments in the
construction of Friedmann-Lema\^itre cosmologies as well as assumptions in
relation to the presence of dark matter, when adopting general relativity as
the gravitational theory. A large section is dedicated to $\Lambda$CDM as the
standard model for structure formation and the arguments that led to its
construction, and to the of role statistics and to the problem of scientific
inference in cosmology as an empirical science. The article concludes with an
outlook on current and future developments in cosmology.
