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

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 goes through a period of acceleration, before settling down to a coasting FLRW geometry with scale parameter a(t) ~ t. This is qualitatively close to observation without any fine-tuning, irrespective of the detailed matter content of the universe.