The Infolding Universe Cosmic Expansion and Black Holes as Calabi-Yau Geometry

Abstract. We propose a geometric reinterpretation of cosmic expansion in which the observable universe occupies the interior of a dynamically evolving Calabi-Yau manifold. In this framework, what observers perceive as the expansion of four-dimensional spacetime is a projection effect of higher-dimensional geometric evolution—the manifold curving inward in its extra dimensions, a process we term infolding. We further propose that black holes correspond to topological gaps in the Calabi-Yau structure—places where the manifold’s topology opens into higher-dimensional cycles. This identification reframes the black hole singularity as a topological feature rather than a point of infinite density, offers a geometric basis for the information paradox, and suggests a natural relationship between cosmic expansion and black hole formation through topological transitions. We identify existing mathematical structures in string theory—conifold transitions, moduli evolution, and Hodge number classification—that could formalize these conjectures, derive the Kaluza-Klein projection identity linking internal volume contraction to external scale factor growth, show that the same identity applied locally near a conifold point yields an effective metric with event-horizon behavior, and specify observational signatures—including topological anisotropy of the Hubble parameter and cycle-constrained black hole mass spectra—that would distinguish this framework from standard ΛCDM cosmology.