Comments on the cosmological constant in generalized uncertainty models

TL;DR

This paper investigates whether generalized uncertainty principle models, inspired by quantum gravity, can resolve the cosmological constant problem by altering quantum field theory phase space, but finds significant limitations in their current form.

Contribution

The study critically examines GUP models' potential to solve the cosmological constant problem and highlights their current shortcomings in addressing this fundamental issue.

Findings

GUP models modify quantum field phase space.

These modifications impact zero-point energy calculations.

Current GUP models are unlikely to solve the cosmological constant problem.

Abstract

The existence of a small, non-zero cosmological constant is one of the major puzzles in fundamental physics. Naively, quantum field theory arguments would imply a cosmological constant which is up to 10$^{120}$ times larger than the observed one. It is believed a comprehensive theory of quantum gravity would resolve this enormous mismatch between theory and observation. In this work, we study the ability of generalized uncertainty principle (GUP) models, which are phenomenologically motivated models of quantum gravity, to address the cosmological constant problem. In particular, we focus on how these GUP models may change the phase space of QFT, and how this affects the momentum space integration of the zero-point energies of normal modes of fields. We point out several issues that make it unlikely that GUP models, in their current form, would be able to adequately address the cosmological constant problem.