Functional Analysis and Its Applications

, Volume 45, Issue 4, pp 241–251 | Cite as

On the space of symmetric operators with multiple ground states

  • A. A. AgrachevEmail author


We study the homology structure of the filtration of the space of self-adjoint operators by the multiplicity of the ground state. We consider only operators acting on a finite-dimensional complex or real Hilbert space, but infinite-dimensional generalizations are easy to guess.

Key words

self-adjoint operator multiple eigenvalue exact sequence 


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Copyright information

© Springer-Verlag 2011

Authors and Affiliations

  1. 1.Scuola Internazionale Superiore di Studi AvanzatiTrieste Steklov Mathematical InstituteMoscowRussia

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