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Quasi-quantum groups from strings

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 نشر من قبل Thomas Krajewski
 تاريخ النشر 2007
  مجال البحث
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Motivated by string theory on the orbifold ${cal M}/G$ in presence of a Kalb-Ramond field strength $H$, we define the operators that lift the group action to the twisted sectors. These operators turn out to generate the quasi-quantum group $D_{omega}[G]$, introduced in the context of conformal field theory by R. Dijkgraaf, V. Pasquier and P. Roche, with $omega$ a 3-cocycle determined by a series of cohomological equations in a tricomplex combining de Rham, u{C}ech and group cohomologies. We further illustrate some properties of the quasi-quantum group from a string theoretical point of view.


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