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arXiv · 0705.2891

Weakly commensurable arithmetic groups, lengths of closed geodesics and isospectral locally symmetric spaces

Gopal Prasad·Andrei S. Rapinchuk
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Abstract

We introduce the notion of weak commensurabilty of arithmetic subgroups and relate it to the length equivalence and isospectrality of locally symmetric spaces. We prove many strong consequences of weak commensurabilty and derive from these many interesting results about isolength and isospectral locally symmetric spaces.

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Gopal Prasad, Andrei S. Rapinchuk. 2008-11-03. Weakly commensurable arithmetic groups, lengths of closed geodesics and isospectral locally symmetric spaces. https://doi.org/10.1007/s10240-009-0019-6

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