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UV/IR Mixing in Noncommutative Field Theories and Open Closed String Duality

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 نشر من قبل Swarnendu Sarkar
 تاريخ النشر 2006
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 تأليف Swarnendu Sarkar




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In this paper we study the phenomenon of UV/IR mixing in noncommutative field theories from the point of view of world-sheet open-closed duality in string theory. New infrared divergences in noncommutative field theories arise as a result of integrating over high momentum modes in the loops. These are believed to come from integrating out additional bulk closed string modes. We analyse this issue in detail for the bosonic theory and further for the supersymmetric theory on the $C^2/Z_2$ orbifold. We elucidate on the exact role played by the constant background $B$-field in this correspondence.

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