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arXiv · 2201.12217

Non-local partner to the cosmological constant

John F. Donoghue
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Abstract

I show that quantum corrections due to a massive particle generates a non-local term in the gravitational effective action which is of zeroth order in the derivative expansion, much like the cosmological constant. It carries a fixed coefficient which is very much larger than the cosmological constant, and which cannot be fine-tuned. The interaction is active at scales above the particle's mass. This is of the form $m^4 (\frac1{\Box}R)_x " " (\frac1{\Box}R)_y$, and I discuss the meaning of $ " " $ and other aspects of its interpretation.

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John F. Donoghue. 2022-01-28. Non-local partner to the cosmological constant. https://doi.org/10.1103/physrevd.105.105025

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