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Conformal invariance from scale invariance in non-linear sigma models

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 نشر من قبل Yu Nakayama
 تاريخ النشر 2020
  مجال البحث
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 تأليف Yu Nakayama




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There exists a certain argument that in even dimensions, scale invariant quantum field theories are conformal invariant. We may try to extend the argument in $2n + epsilon$ dimensions, but the naive extension has a small loophole, which indeed shows an obstruction in non-linear sigma models in $2+epsilon$ dimensions. Even though it could have failed due to the loophole, we show that scale invariance does imply conformal invariance of non-linear sigma models in $2+epsilon$ dimension from the seminal work by Perelman on the Ricci flow.



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