Sergey Alexandrov  教授学术报告

Title: Quantum Calabi-Yau geometry, black holes & black rings

Speaker: Sergey Alexandrov

Affiliation: University of Montpellier, France （法国蒙彼利埃大学）

Time: 16:00 - 17:00, Friday,  9th October, 2026 (UTC+8, Beijing Time)

Venue: Zoom Meeting (ID: 385 442 0225; Passcode: yauc)

Inviter: Jie Gu (顾杰)

Abstract

Recently, the use of wall-crossing and modularity allowed to compute various topological invariants of Calabi-Yau threefolds for charges that were previously unreachable. I'll present the analysis of these invariants that, on the one hand, reveals many interesting features such as their phase transitions and, on the other hand, matches them against quantum corrected entropy of black holes and black rings. For GV invariants, I'll derive an exact asymptotics for large degree and fixed genus, and an approximate formula where the genus is not fixed. I'll also discuss various puzzles raised by the presented results.

Speaker

Sergey Alexandrov is a CNRS Directeur de recherche at the Laboratoire Charles Coulomb, University of Montpellier. He is a theoretical physicist working on string theory, quantum gravity, and mathematical physics. His research focuses on non-perturbative aspects of string compactifications and supersymmetric theories, including BPS and Donaldson–Thomas invariants, wall-crossing, twistor methods, modular and mock-modular structures, quantum dilogarithms, and topological strings. He received his PhD in theoretical physics in 2003 and has been based in Montpellier since 2005.

The seminar will be broadcasted online by Zoom.

Interested people are free to join, without registration in advance.

The Zoom info is

URL: https://us02web.zoom.us/j/3854420225?pwd=SXY4eWJKOTBFZWJDaE16aXpTamY1QT09

Meeting ID: 385 442 0225

Passcode: yauc