English

A monotonicity theorem for subharmonic functions on manifolds

Classical Analysis and ODEs 2025-11-11 v2

Abstract

We provide a sharp monotonicity theorem about the distribution of subharmonic functions on manifolds, which can be regarded as a new, measure theoretic form of the uncertainty principle. As an illustration of the scope of this result, we deduce contractivity estimates for analytic functions on the Riemann sphere, the complex plane and the Poincar\'e disc, with a complete description of the extremal functions, hence providing a unified and illuminating perspective of a number of results and conjectures on this subject, in particular on the Wehrl entropy conjecture by Lieb and Solovej. In this connection, we completely prove that conjecture for SU(2), by showing that the corresponding extremals are only the coherent states. Also, we show that the above (global) estimates admit a local counterpart and in all cases we characterize also the extremal subsets, among those of fixed assigned measure.

Keywords

Cite

@article{arxiv.2212.14008,
  title  = {A monotonicity theorem for subharmonic functions on manifolds},
  author = {Aleksei Kulikov and Fabio Nicola and Joaquim Ortega-Cerdà and Paolo Tilli},
  journal= {arXiv preprint arXiv:2212.14008},
  year   = {2025}
}

Comments

Fixed a few typos

R2 v1 2026-06-28T07:55:08.753Z