Quantum Gravity Corrections and Entropy at the Planck time

TL;DR

This paper explores how Quantum Gravity modifies fundamental Planck scale quantities during the universe's early moments, finding they are significantly larger, but the entropy at the Planck time remains unchanged, supporting the holographic principle.

Contribution

It demonstrates that Quantum Gravity effects enlarge Planck quantities while preserving the entropy, highlighting potential implications for early universe cosmology and the holographic principle.

Findings

Planck quantities increase by factors of 10-10^4 due to Quantum Gravity.

Dimensionless entropy at the Planck time remains unchanged.

Results suggest modifications in cosmological models from the Planck era onward.

Abstract

We investigate the effects of Quantum Gravity on the Planck era of the universe. In particular, using different versions of the Generalized Uncertainty Principle and under specific conditions we find that the main Planck quantities such as the Planck time, length, mass and energy become larger by a factor of order 10-10^{4} compared to those quantities which result from the Heisenberg Uncertainty Principle. However, we prove that the dimensionless entropy enclosed in the cosmological horizon at the Planck time remains unchanged. These results, though preliminary, indicate that we should anticipate modifications in the set-up of cosmology since changes in the Planck era will be inherited even to the late universe through the framework of Quantum Gravity (or Quantum Field Theory) which utilizes the Planck scale as a fundamental one. More importantly, these corrections will not affect the entropic content of the universe at the Planck time which is a crucial element for one of the basic principles of Quantum Gravity named Holographic Principle.