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تسجيل مستخدم جديدCharacteristic classes in general relativity on a modified Poincare curvature bundle
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تأليف
Yoshimasa Kurihara
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Characteristic classes in space-time manifolds are discussed for both even- and odd-dimensional spacetimes. In particular, it is shown that the Einstein--Hilbert action is equivalent to a second Chern-class on a modified Poincare bundle in four dimensions. Consequently, the cosmological constant and the trace of an energy-momentum tensor become divisible modulo R/Z.
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