Dark Energy from Quantum Gravity Discreteness

Alejandro Perez and Daniel Sudarsky
Phys. Rev. Lett. 122, 221302 – Published 7 June 2019

Abstract

We argue that discreteness at the Planck scale (naturally expected to arise from quantum gravity) might manifest in the form of minute violations of energy-momentum conservation of the matter degrees of freedom when described in terms of (idealized) smooth fields on a smooth spacetime. In the context of applications to cosmology, such “energy diffusion” from the low energy matter degrees of freedom to the discrete structures underlying spacetime would lead to the emergence of an effective dark energy term in Einstein’s equations. We estimate this effect using a (relational) hypothesis about the materialization of discreteness in quantum gravity which is motivated by the strict observational constraints supporting the validity of Lorentz invariance at low energies. Arguments based on a simple dimensional analysis lead to an estimate of an effective cosmological constant agreeing in order of magnitude with its observed value. If correct, this would constitute remarkable empirical evidence for a Planckian granular aspect of spacetime.

  • Figure
  • Received 24 January 2018
  • Revised 14 November 2018

DOI:https://doi.org/10.1103/PhysRevLett.122.221302

© 2019 American Physical Society

Physics Subject Headings (PhySH)

Gravitation, Cosmology & AstrophysicsParticles & Fields

Authors & Affiliations

Alejandro Perez

  • Aix Marseille Université, Université de Toulon, CNRS, CPT, 13000 Marseille, France

Daniel Sudarsky

  • Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, México D.F. 04510, México and Department of Philosophy, New York University, New York, New York 10003, USA

Article Text (Subscription Required)

Click to Expand

References (Subscription Required)

Click to Expand
Issue

Vol. 122, Iss. 22 — 7 June 2019

Reuse & Permissions
Access Options
Author publication services for translation and copyediting assistance advertisement

Authorization Required


×
×

Images

×

Sign up to receive regular email alerts from Physical Review Letters

Log In

Cancel
×

Search


Article Lookup

Paste a citation or DOI

Enter a citation
×