Cosmological test of an ultraviolet origin of Dark Energy

TL;DR

This paper proposes a testable model where black holes drive cosmic acceleration without a cosmological constant, but it shows poor agreement with supernova data, challenging the idea of black hole-driven dark energy.

Contribution

It introduces a novel model linking black hole mass functions to cosmic expansion and tests its predictions against supernova data, offering an alternative to the cosmological constant.

Findings

Black hole-based model poorly fits SN1a data

Alternative velocity dispersion model cannot be excluded by current data

Provides a framework to test ultraviolet-origin dark energy theories

Abstract

The accelerated expansion of the Universe is impressively well described by a cosmological constant. However, the observed value of the cosmological constant is much smaller than expected based on quantum field theories. Recent efforts to achieve consistency in these theories have proposed a relationship between Dark Energy and the most compact objects, such as black holes (BH). However, experimental tests are very challenging to devise and perform. In this article, we present a testable model with no cosmological constant, in which the accelerated expansion can be driven by black holes. The model couples the expansion of the Universe (the Friedmann equation) with the mass-function of cosmological haloes (using the Press-Schechter formalism). Through the observed link between halo-masses and BH-masses one thus gets a coupling between the expansion rate of the Universe and the BHs. We compare the predictions of this simple BH model with SN1a data and find a poor agreement with observations. Our method is sufficiently general that it allows us to also test a fundamentally different model, also without a cosmological constant, where the accelerated expansion is driven by a new force proportional to the internal velocity dispersion of galaxies. Surprisingly enough this model cannot be excluded using the SN1a data.