Cyclic cosmological models offer alternatives to the standard inflationary paradigm, but the physical mechanism governing the transition between successive cycles remains insufficiently constrained. This exploratory work proposes that quantum entanglement saturation could provide such a mechanism. We introduce the Instability of Cosmic Coherence (ICC) hypothesis, according to which, in the late universe—dominated by photons and approaching thermodynamic equilibrium—quantum correlations accumulate until reaching a critical threshold. Drawing on recent developments in quantum gravity, particularly the ER=EPR correspondence (Maldacena & Susskind, 2013) and the Ryu-Takayanagi formula (2006) linking entanglement entropy to spacetime geometry, we argue that maximal entanglement leads to geometric degeneracy rather than a stable heat death. This instability, analogous to false vacuum decay, could trigger a transition to a new cosmological cycle. The ICC hypothesis distinguishes itself from existing cyclic models—Penrose's Conformal Cyclic Cosmology and the ekpyrotic scenario—through its reliance on informational mechanisms rather than geometric or extra-dimensional ones. The paper examines the theoretical foundations of this proposal and generates testable qualitative predictions: CMB anomalies at large angular scales, dynamic dark energy (w > −1), and structural correlations between cosmological observables. This work adopts an explicit epistemological classification distinguishing three levels: established physics (Level I), plausible theoretical extrapolations (Level II), and speculative hypotheses (Level III). The ICC hypothesis falls under Level III: a disciplined speculation, coherent with established physics but not derived from first principles. Its value lies in the questions it raises and the connections it suggests between cosmology, quantum information, and gravity.
DIDIER AUBOURG (Tue,) studied this question.