A (simple) classical algorithm for estimating Betti numbers

Autor: Simon Apers, Sander Gribling, Sayantan Sen, Dániel Szabó
Jazyk: angličtina
Rok vydání: 2023
Předmět:
Zdroj: Quantum, Vol 7, p 1202 (2023)
Druh dokumentu: article
ISSN: 2521-327X
DOI: 10.22331/q-2023-12-06-1202
Popis: We describe a simple algorithm for estimating the $k$-th normalized Betti number of a simplicial complex over $n$ elements using the path integral Monte Carlo method. For a general simplicial complex, the running time of our algorithm is $n^{O\left(\frac{1}{\sqrt{\gamma}}\log\frac{1}{\varepsilon}\right)}$ with $\gamma$ measuring the spectral gap of the combinatorial Laplacian and $\varepsilon \in (0,1)$ the additive precision. In the case of a clique complex, the running time of our algorithm improves to $\left(n/\lambda_{\max}\right)^{O\left(\frac{1}{\sqrt{\gamma}}\log\frac{1}{\varepsilon}\right)}$ with $\lambda_{\max} \geq k$, where $\lambda_{\max}$ is the maximum eigenvalue of the combinatorial Laplacian. Our algorithm provides a classical benchmark for a line of quantum algorithms for estimating Betti numbers. On clique complexes it matches their running time when, for example, $\gamma \in \Omega(1)$ and $k \in \Omega(n)$.
Databáze: Directory of Open Access Journals