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A note on the Poincare and Cheeger inequalities for simple random walk on a connected graph

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 نشر من قبل John Pike
 تاريخ النشر 2012
  مجال البحث
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 تأليف John Pike




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In 1991, Persi Diaconis and Daniel Stroock obtained two canonical path bounds on the second largest eigenvalue for simple random walk on a connected graph, the Poincare and Cheeger bounds, and they raised the question as to whether the Poincare bound is always superior. In this paper, we present some background on these issues, provide an example where Cheeger beats Poincare, establish some sufficient conditions on the canonical paths for the Poincare bound to triumph, and show that there is always a choice of paths for which this happens.



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