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Renormalization and causality violations in classical gravity coupled with quantum matter

Damiano Anselmi
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Abstract

I prove that classical gravity coupled with quantized matter can be renormalized with a finite number of independent couplings, plus field redefinitions, without introducing higher-derivative kinetic terms in the gravitational sector, but adding vertices that couple the matter stress-tensor with the Ricci tensor. The theory is called "acausal gravity", because it predicts the violation of causality at high energies. Renormalizability is proved by means of a map M that relates acausal gravity with higher-derivative gravity. The causality violations are governed by two parameters, a and b, that are mapped by M into higher-derivative couplings. At the tree level causal prescriptions exist, but they are spoiled by the one-loop corrections. Some ideas are inspired by the usual treatments of the Abraham-Lorentz force in classical electrodynamics.

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Damiano Anselmi. 2007-01-15. Renormalization and causality violations in classical gravity coupled with quantum matter. https://doi.org/10.1088/1126-6708%2F2007%2F01%2F062

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