On the Cosmological Constant Problem
نویسنده
چکیده
We prove that Weyl invariant theories of gravity possess a remarkable property which, under very general assumptions, explains the stability of flat space-time. We show explicitly how conformal invariance is broken spontaneously by the vacuum expectation value of an unphysical scalar field; this process induces general relativity as an effective long distance limit. We show that all ghost degrees of freedom acquire gauge fixing dependent masses, strongly suggest,ing the unitarity of the theory.
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تاریخ انتشار 1984