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Phantom singularities and their quantum fate: general relativity and beyond—a CANTATA COST action topic

  • Mariam Bouhmadi-López
  • Claus Kiefer
  • Prado Martín-MorunoEmail author
Invited Report: Introduction to Current Research

Abstract

Cosmological observations allow the possibility that dark energy is caused by phantom fields. These fields typically lead to the occurrence of singularities in the late Universe. We review here the status of phantom singularities and their possible avoidance in a quantum theory of gravity. We first introduce phantom energy and discuss its behavior in cosmology. We then list the various types of singularities that can occur from its presence. We also discuss the possibility that phantom behavior is mimicked by an alternative theory of gravity. We finally address the quantum cosmology of these models and discuss in which sense the phantom singularities can be avoided.

Keywords

Phantom energy Alternative theories of gravity Cosmological singularities Quantum cosmology 

Notes

Acknowledgements

The work of MBL is supported by the Basque Foundation of Science IKERBASQUE. She also wishes to acknowledge the partial support from the Basque government Grant No. IT956-16 (Spain) and and FONDOS FEDER under grant FIS2017- 85076-P (MINECO/AEI/FEDER, UE). PMM acknowledges financial support from the project FIS2016-78859-P (AEI/FEDER, UE). This article is based upon work from COST Action CA15117 (CANTATA), supported by COST (European Cooperation in Science and Technology) www.cost.eu.

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Authors and Affiliations

  1. 1.Department of Theoretical PhysicsUniversity of the Basque Country UPV/EHUBilbaoSpain
  2. 2.IKERBASQUE, Basque Foundation for ScienceBilbaoSpain
  3. 3.Institute for Theoretical PhysicsUniversity of CologneCologneGermany
  4. 4.Departamento de Física Teórica and Instituto de Física de Partículas y del Cosmos (IPARCOS)Universidad Complutense de MadridMadridSpain

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