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Spectral averaging for trace compatible operators

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 نشر من قبل Nurulla Azamov
 تاريخ النشر 2007
  مجال البحث
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In this note the notions of trace compatible operators and infinitesimal spectral flow are introduced. We define the spectral shift function as the integral of infinitesimal spectral flow. It is proved that the spectral shift function thus defined is absolutely continuous and Kreins formula is established. Some examples of trace compatible affine spaces of operators are given.



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