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arXiv · 1503.06099

QED trace anomaly, non-local Lagrangians and quantum Equivalence Principle violations

John F. Donoghue·Basem Kamal El-Menoufi
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Abstract

We discuss the derivation of the trace anomaly using a non-local effective action at one loop. This provides a simple and instructive form and emphasizes infrared physics. We then use this example to explore several of the properties of non-local actions, including displaying the action for the full non-local energy-momentum tensor. As an application, we show that the long-distance corrections at one loop lead to quantum violations of some classical consequences of the equivalence principle, for example producing a frequency dependence of the gravitational bending of light.

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John F. Donoghue, Basem Kamal El-Menoufi. 2015-03-20. QED trace anomaly, non-local Lagrangians and quantum Equivalence Principle violations. https://arxiv.org/abs/1503.06099

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