Gromov's dihedral rigidity conjecture in dimension three

In this article, we present a self-contained proof of Gromov's dihedral rigidity conjecture on scalar curvature in the three-dimensional case.

The proof avoids many of the technical complications that arise in higher dimensions, while still illustrating the essential ideas of the general approach developed in arXiv:2112.01510 (version 6) and arXiv:2203.09511.

It is significantly shorter than the proof of the general case and is intended to be more accessible.