The Big Bang as a Mirror: a Solution of the Strong CP Problem

TL;DR

This paper proposes a novel cosmological solution to the strong CP problem by interpreting the Big Bang as a mirror boundary condition, linking boundary reflections with fermion chirality and left-right symmetry.

Contribution

It introduces a new perspective on the Big Bang as a mirror boundary, connecting boundary conditions with fermion chirality and providing a CP problem solution without axions.

Findings

Big Bang as a mirror boundary condition

Connection between boundary reflections and fermion chirality

Solution to the strong CP problem without axions

Abstract

We argue that the Big Bang can be understood as a type of mirror. We show how reflecting boundary conditions for spinors and higher spin fields are fixed by local Lorentz and gauge symmetry, and how a temporal mirror (like the Bang) differs from a spatial mirror (like the AdS boundary), providing a possible explanation for the observed pattern of left- and right-handed fermions. By regarding the Standard Model as the limit of a minimal left-right symmetric theory, we obtain a new, cosmological solution of the strong $CP$ problem, without an axion.