{"title":"Computation of the von Neumann entropy of large matrices via trace estimators and rational Krylov methods","authors":"Michele Benzi, Michele Rinelli, Igor Simunec","doi":"10.1007/s00211-023-01368-6","DOIUrl":null,"url":null,"abstract":"Abstract We consider the problem of approximating the von Neumann entropy of a large, sparse, symmetric positive semidefinite matrix A , defined as $${{\\,\\textrm{tr}\\,}}(f(A))$$ <mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\"> <mml:mrow> <mml:mrow> <mml:mspace /> <mml:mtext>tr</mml:mtext> <mml:mspace /> </mml:mrow> <mml:mo>(</mml:mo> <mml:mi>f</mml:mi> <mml:mo>(</mml:mo> <mml:mi>A</mml:mi> <mml:mo>)</mml:mo> <mml:mo>)</mml:mo> </mml:mrow> </mml:math> where $$f(x)=-x\\log x$$ <mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\"> <mml:mrow> <mml:mi>f</mml:mi> <mml:mo>(</mml:mo> <mml:mi>x</mml:mi> <mml:mo>)</mml:mo> <mml:mo>=</mml:mo> <mml:mo>-</mml:mo> <mml:mi>x</mml:mi> <mml:mo>log</mml:mo> <mml:mi>x</mml:mi> </mml:mrow> </mml:math> . After establishing some useful properties of this matrix function, we consider the use of both polynomial and rational Krylov subspace algorithms within two types of approximations methods, namely, randomized trace estimators and probing techniques based on graph colorings. We develop error bounds and heuristics which are employed in the implementation of the algorithms. Numerical experiments on density matrices of different types of networks illustrate the performance of the methods.","PeriodicalId":49733,"journal":{"name":"Numerische Mathematik","volume":null,"pages":null},"PeriodicalIF":2.1000,"publicationDate":"2023-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"2","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Numerische Mathematik","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1007/s00211-023-01368-6","RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"MATHEMATICS, APPLIED","Score":null,"Total":0}
引用次数: 2
Abstract
Abstract We consider the problem of approximating the von Neumann entropy of a large, sparse, symmetric positive semidefinite matrix A , defined as $${{\,\textrm{tr}\,}}(f(A))$$ tr(f(A)) where $$f(x)=-x\log x$$ f(x)=-xlogx . After establishing some useful properties of this matrix function, we consider the use of both polynomial and rational Krylov subspace algorithms within two types of approximations methods, namely, randomized trace estimators and probing techniques based on graph colorings. We develop error bounds and heuristics which are employed in the implementation of the algorithms. Numerical experiments on density matrices of different types of networks illustrate the performance of the methods.
期刊介绍:
Numerische Mathematik publishes papers of the very highest quality presenting significantly new and important developments in all areas of Numerical Analysis. "Numerical Analysis" is here understood in its most general sense, as that part of Mathematics that covers:
1. The conception and mathematical analysis of efficient numerical schemes actually used on computers (the "core" of Numerical Analysis)
2. Optimization and Control Theory
3. Mathematical Modeling
4. The mathematical aspects of Scientific Computing