English

Deriving Perelman's entropy from Colding's monotonic volume

Differential Geometry 2025-07-17 v3 Analysis of PDEs

Abstract

In his groundbreaking work from 2002, Perelman introduced two fundamental monotonic quantities: the reduced volume and the entropy. While the reduced volume was motivated by the Bishop-Gromov volume comparison applied to a suitably constructed NN-space, which becomes Ricci-flat as NN\rightarrow \infty, Perelman did not provide a corresponding explanation for the origin of the entropy. In this article, we demonstrate that Perelman's entropy emerges as the limit of Colding's monotonic volume for harmonic functions on Ricci-flat manifolds, when appropriately applied to Perelman's NN-space.

Keywords

Cite

@article{arxiv.2501.12949,
  title  = {Deriving Perelman's entropy from Colding's monotonic volume},
  author = {Ignacio Bustamante and Martin Reiris},
  journal= {arXiv preprint arXiv:2501.12949},
  year   = {2025}
}

Comments

Final version. To appear in Crelle's journal

R2 v1 2026-06-28T21:13:43.123Z