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arXiv · 2312.14612

A Universe from a Lagrangian Fixed Point

Pedro D. Alvarez·Benjamin Koch·Ali Riahinia·Angel Rincon
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Abstract

In this paper, we investigate the theoretical possibility that a Lagrangian fixed point, when applied to cosmological models, can drive dynamical evolution towards a bouncing universe. We analyze the physics of a Lagrangian fixed point within the context of a gravitational average effective action featuring scale-dependent couplings. To explore this concept, we develop a toy model set in a four-dimensional, spatially flat spacetime, anchored by a Lagrangian fixed point. Solving the cosmological equations of this model analytically, we identify several non-trivial solution branches. These branches are characterized by a modified scale factor and dynamic gravitational couplings, offering new insights into the behavior of cosmological models under these conditions.

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Pedro D. Alvarez, Benjamin Koch, Ali Riahinia, Angel Rincon. 2024-10-08. A Universe from a Lagrangian Fixed Point. https://doi.org/10.1016/j.dark.2024.101674

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