English

Microstate Counting for rotating (type~II) isolated horizons

General Relativity and Quantum Cosmology 2026-03-23 v1

Abstract

We present a proposal for black hole microstate counting in Loop Quantum Gravity (LQG) for rotating (type~II) isolated horizons. The key obstacle in extending the standard nonrotating entropy derivation arises from the θ\theta-dependent rotation 1-form, which breaks the global Chern--Simons (CS) structure on the horizon. We propose a local decomposition of the horizon S2S^2 into narrow concentric rings, each approximated as a locally nonrotating patch with a constant effective CS level. Each ring is quantized independently using standard LQG techniques, and the total entropy is obtained by integrating over the entire horizon. This method restores a local CS description, includes the contribution of angular momentum, and is consistent with the first law of black hole mechanics.

Keywords

Cite

@article{arxiv.2603.19763,
  title  = {Microstate Counting for rotating (type~II) isolated horizons},
  author = {Pritam Nanda},
  journal= {arXiv preprint arXiv:2603.19763},
  year   = {2026}
}
R2 v1 2026-07-01T11:29:30.863Z