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Anomalies and gravity

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 نشر من قبل Eckehard Mielke W.
 تاريخ النشر 2006
  مجال البحث
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Anomalies in Yang-Mills type gauge theories of gravity are reviewed. Particular attention is paid to the relation between the Dirac spin, the axial current j_5 and the non-covariant gauge spin C. Using diagrammatic techniques, we show that only generalizations of the U(1)- Pontrjagin four--form F^ F= dC arise in the chiral anomaly, even when coupled to gravity. Implications for Ashtekars canonical approach to quantum gravity are discussed.



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