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Action integrals and infinitesimal characters

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 نشر من قبل Andr\\.es Vi\\~na
 تاريخ النشر 2009
  مجال البحث
والبحث باللغة English
 تأليف Andres Vi~na




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Let $G$ be a reductive Lie group and ${mathcal O}$ the coadjoint orbit of a hyperbolic element of ${frak g}^*$. By $pi$ is denoted the unitary irreducible representation of $G$ associated with ${mathcal O}$ by the orbit method. We give geometric interpretations in terms of concepts related to ${mathcal O}$ of the constant $pi(g)$, for $gin Z(G)$. We also offer a description of the invariant $pi(g)$ in terms of action integrals and Berry phases. In the spirit of the orbit method we interpret geometrically the infinitesimal character of the differential representation of $pi$.

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