A Relation between Gravity in (3 + 1)–dimensions and Pontrjagin Topological Invariant
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چکیده
A relation between the MacDowell-Mansouri theory of gravity and the Pontrjagin toplogical invariant in (3 + 1) dimensions is discussed. This relation may be of especial interest in the quest of finding a mechanism to go from non-dynamical to dynamical gravity.
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تاریخ انتشار 1995