On Internal Consistency of Holographic Dark Energy Models

TL;DR

This paper examines the internal consistency of holographic dark energy models, revealing fundamental conflicts with quantum field theory constraints during the radiation-dominated epoch of the universe.

Contribution

It demonstrates that holographic dark energy models cannot satisfy quantum field theory restrictions in the early universe, challenging their viability.

Findings

HDE models conflict with QFT constraints in radiation era

UV/IR connection issues in early universe

Limitations of HDE in standard cosmological epochs

Abstract

Holographic dark energy (HDE) models, underlain by an effective quantum field theory (QFT) with a manifest UV/IR connection, have become a convincing candidate for the dark energy in the universe. On the other hand, the maximum number of quantum states a conventional QFT in the box of size $L$ is capable to describe, refer to those boxes which are on the brink of experiencing a sudden collapse to a black hole. Another restriction on the underlying QFT is that the UV cutoff, which cannot be chosen independently of the IR cutoff and therefore becomes a function of time in a cosmological setting, should stay the largest energy scale even in the standard cosmological epochs preceding a dark energy dominated one. We show that, irrespective of whether one deals with the saturated form of HDE or takes a certain degree of non-saturation in the past, the above restrictions cannot be met in a radiation-dominated universe, an epoch in the history of the universe which is expected to be perfectly describable within conventional QFT.