The rapid expansion of the early universe might have been caused by quantum information loss rather than a mysterious new particle.
April 23, 2026
Original Paper
Internal Decoherence in a Closed-system Cosmology Induces an Effective Stress-Energy Component and Governs Early-Universe Dynamics
SSRN · 6498319
The Takeaway
Inflation theory suggests the universe expanded faster than light in its first moments, but no one knows what triggered it. This new model shows that the first act of quantum decoherence, where quantum information is lost to the environment, creates enough energy to drive that expansion. This means we don't need a theoretical inflaton field to explain the birth of the universe. The simple process of quantum systems interacting with each other produces an effective stress-energy that pushes space outward. This shifts the focus of cosmology from searching for new particles to studying the laws of information. It provides a more elegant and grounded explanation for how everything began.
From the abstract
We propose a semiclassical mechanism in which the first local act of decoherence in a closed quantum matter sector generates an effective stress-energy component that can drive early-Universe acceleration and set primordial initial conditions. We work with quantum fields on a classical, globally hyperbolic spacetime and model the act as a local GKSL (Lindblad) map that is completely positive, trace-preserving, and compatible with microcausality and no-signaling. Using the first law of entangleme