Our universe might have a 'mirror twin' out there where time runs backward and everything is flipped inside out.
March 25, 2026
Original Paper
CPT Violation, Mirror World and Implications for Baryon Asymmetry
arXiv · 2603.22381
The Takeaway
This model suggests a globally symmetric system that solves the mystery of why there is more matter than antimatter. It provides a geometric reason for the 'arrow of time' without requiring complex initial conditions.
From the abstract
We propose a novel model in which the Universe is created as a pair of coordinate-reversed counterparts, forming a globally CPT-symmetric system that permits local CPT violations within each sector. This framework naturally introduces a mirror universe with opposite chiralities and reversed microscopic time coordinates, providing a geometric interpretation of time reversal without relying on initial-final state interchange. We investigate the consequences of local CPT violation in each universe,