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arXiv · 2310.11126

One-loop effective action of the IKKT model for cosmological backgrounds

Emmanuele Battista·Harold C. Steinacker
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Abstract

We study cosmological solutions of the IKKT model with $k=-1$ FLWR geometry, taking into account one-loop corrections. A previously discussed covariant quantum spacetime is found to be stabilized through one-loop effects at early times, without adding a mass term to the model. At late times, this background is modified and approaches a solution of the classical model where $a(t) \sim const$, but the dilaton decreases in time. This suggests that a more complete treatment of the system is required in the late-time regime.

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Emmanuele Battista, Harold C. Steinacker. 2023-10-17. One-loop effective action of the IKKT model for cosmological backgrounds. https://doi.org/10.1007/jhep01(2024)125

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