گروه کیهان‌شناسی

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Title:

گرانش جرم‌دار هندسی در فرمول‌بندی چند هم بستاری

 (Geometric massive gravity in multi-connection formalism)

Abstract: What is the right way to interpret a massive graviton? We generalize the kinematical framework of general relativity to multiple connections. The average of the connections is itself a connection and plays the role of the canonical connection in standard General Relativity. At the level of dynamics, the simplest choice of the Einstein-Hilbert action is indistinguishable from the single-connection case. However, inspired by Weyl geometry, we show how one can construct massive gravity to all orders in perturbation theory compatible with the de Rham-Gabadadze-Tolley ghost-free model. We conclude that the mass of the graviton can be interpreted as a geometrical property of spacetime arising from two connections. Furthermore in the multi-connection framework there is no ambiguity in the definition of physical metric and consequently coupling to matter.

این سمینار در روز یکشنبه ۲۷ بهمن ۱۳۹۲ساعت ۱۵ در اتاق شورا  در طبقهٔ پنجم دانشکدهٔ فیزیک برگزار خواهد شد.