Formal pseudodifferential operators and Witten’s r-spin numbers

Autor: Kefeng Liu, Ravi Vakil, Hao Xu
Rok vydání: 2014
Předmět:
Zdroj: Journal für die reine und angewandte Mathematik (Crelles Journal). 2017:1-33
ISSN: 1435-5345
0075-4102
Popis: We derive an effective recursion for Witten’s r-spin intersection numbers, using Witten’s conjecture relating r-spin numbers to the Gel’fand–Dikii hierarchy. Consequences include closed-form descriptions of the intersection numbers (for example, in terms of gamma functions). We use these closed-form descriptions to prove Harer–Zagier’s formula for the Euler characteristic of ℳ g , 1 {\mathcal{M}_{g,1}} . Finally, we extend Witten’s series expansion formula for the Landau–Ginzburg potential to study r-spin numbers in the small phase space in genus zero. Our key tool is the calculus of formal pseudodifferential operators, and is partially motivated by work of Brézin and Hikami.
Databáze: OpenAIRE