Noncommutative geometry on the Berkovich projective line
Functional Analysis
2026-04-10 v2 Number Theory
Operator Algebras
Quantum Algebra
Abstract
We construct several -algebras and spectral triples associated to the Berkovich projective line . In the commutative setting, we construct a spectral triple as a direct limit over finite -trees. More general -algebras generated by partial isometries are also presented. We use their representations to associate a Perron-Frobenius operator and a family of projection valued measures. Finally, we show that invariant measures, such as the Patterson-Sullivan measure, can be obtained as KMS-states of the crossed product algebra with a Schottky subgroup of .
Cite
@article{arxiv.2411.02593,
title = {Noncommutative geometry on the Berkovich projective line},
author = {Masoud Khalkhali and Damien Tageddine},
journal= {arXiv preprint arXiv:2411.02593},
year = {2026}
}