A new simulation of the start of everything shows the universe didn't start with a 'bang,' but instead 'bounced' into existence from a previous era.
April 2, 2026
Original Paper
Time evolution of semiclassical states in the one-vertex model of quantum-reduced loop gravity
arXiv · 2604.00999
The Takeaway
General relativity predicts the universe started as an infinitely small point, which is a major problem for physics. This new model suggests that as a previous universe collapsed, quantum effects pushed back like a spring, causing it to rebound into the expansion we see today.
From the abstract
We compute numerically the time evolution of simple semiclassical states describing homogeneous and isotropic spatial geometries in quantum-reduced loop gravity under a deparametrized formulation of the dynamics, in which a reference matter field is taken as a relational time variable for the dynamics of quantum states of the gravitational field. The states which we consider are defined on the Hilbert space of a spin network graph formed by a single six-valent vertex. We find that the quantum dy