New Model Proposes Weyl Invariant Early Universe

Researchers have proposed a new model for the early universe using finite nonlocal quantum gravity, which is Weyl invariant at both classical and quantum levels. The model describes two phases: a Weyl invariant trans-Planckian phase and a post-Planckian or Higgs phase. In the first phase, the model addresses issues of the hot big bang, such as singularity, flatness, and horizon problems, through Weyl invariance. This approach provides a non-inflationary solution that does not depend on the microscopic details of the theory. In the second phase, once Weyl symmetry is spontaneously broken, primordial perturbations are generated around a background that evolves as a radiation-dominated flat Friedmann-Lemaître-Robertson-Walker universe.

This new model offers a different perspective on the early universe, potentially resolving longstanding issues in cosmology without relying on inflation. The implications of this model could lead to a better understanding of the universe's initial conditions and its subsequent evolution. The study's findings could also influence future research in cosmology and quantum gravity, providing a framework for exploring the early universe's dynamics and the role of Weyl invariance in cosmological models.