Cosmological and Black Hole Spacetimes in Twisted Noncommutative Gravity

TL;DR

This paper derives noncommutative Einstein equations for twisted spacetimes, exploring solutions relevant to cosmology and black holes, some of which align with observations while others reveal strong noncommutative effects at small scales.

Contribution

It introduces noncommutative Einstein equations for abelian twists and analyzes their solutions in cosmological and black hole contexts, highlighting physically viable models.

Findings

Some solutions contradict observations and are rejected.

Certain solutions are compatible with low-energy phenomenology.

Strong noncommutativity effects are found at short distances and early times.

Abstract

We derive noncommutative Einstein equations for abelian twists and their solutions in consistently symmetry reduced sectors, corresponding to twisted FRW cosmology and Schwarzschild black holes. While some of these solutions must be rejected as models for physical spacetimes because they contradict observations, we find also solutions that can be made compatible with low energy phenomenology, while exhibiting strong noncommutativity at very short distances and early times.