The idea of gravitational collapse can be traced back to the first solution of Einstein's equations, but in these early stages, compelling evidence to support this idea was lacking. Furthermore, there were many theoretical gaps underlying the conviction that a star could not contract beyond its critical radius. The philosophical views of the early 20th century, especially those of Sir Arthur S. Eddington, imposed equilibrium as an almost unquestionable condition on theoretical models describing stars. This paper is a historical and epistemological account of the theoretical defiance of this equilibrium hypothesis, with a novel reassessment of J.R. Oppenheimer's work on astrophysics. 1 Large-scale-structure physics means, in this case, all disciplines that deal with scales greater than Earth, like astronomy, astrophysics, cosmology, and gravitation.