印度钦奈数学研究所Amitabh Virmani团队研究了一个小黑环的引力指数。该研究于2025年7月17日发表于《高能物理杂志》上。

某些具有角动量的超对称基本弦态可以看作是五维弦理论中的小黑环。这些黑环的视界面积为零。4D-5D连接将这些小环与少一个维度的没有角动量的小黑洞联系起来。最近的工作提出了马鞍解来计算小黑洞的超对称指数，主题是引力路径积分。

研究组提出了一个五维小黑环的模拟鞍形解。主要的贡献来自于一个黑色的环鞍，它在五个维度上在两个独立的平面上旋转，并且具有有限面积的视界。研究组也把鞍形解写为三中心的Bena-Warner解。

附：英文原文

Title: The gravitational index of a small black ring

Author: Bandyopadhyay, Subhodip, Punia, Gurmeet Singh, Srivastava, Yogesh K., Virmani, Amitabh

Issue&Volume: 2025-07-17

Abstract: Certain supersymmetric elementary string states with angular momentum can be viewed as small black rings in a five-dimensional string theory. These black rings have zero area event horizon. The 4D-5D connection relates these small rings to small black holes without angular momentum in one less dimension. Recent works have proposed saddle solutions that compute the supersymmetric index for small black holes using gravitational path integral. In this paper, we propose an analogous saddle solution for a five-dimensional small black ring. The dominant contribution comes from a black ring saddle that rotates in both independent planes in five dimensions and has a finite area event horizon. We also write the saddle solution as a three center Bena-Warner solution.

DOI: 10.1007/JHEP07(2025)200

Source: https://link.springer.com/article/10.1007/JHEP07(2025)200