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arXiv · 2503.17203

Quantum fields and the cosmological constant

Renata Ferrero·Vincenzo Naso·Roberto Percacci
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Abstract

It has been shown that if one solves self-consistently the semiclassical Einstein equations in the presence of a quantum scalar field, with a cutoff on the number of modes, spacetime become flatter when the cutoff increases. Here we extend the result to include the effect of fields with spin 0, 1/2, 1 and 2. With minor adjustments, the main result persists. Remarkably, one can have positive curvature even if the cosmological constant in the bare action is negative.

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Renata Ferrero, Vincenzo Naso, Roberto Percacci. 2025-03-21. Quantum fields and the cosmological constant. https://arxiv.org/abs/2503.17203

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