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Title: Unified dark energy-dark matter model with inverse quintessence

Abstract

We consider a model where both dark energy and dark matter originate from the coupling of a scalar field with a non-canonical kinetic term to, both, a metric measure and a non-metric measure. An interacting dark energy/dark matter scenario can be obtained by introducing an additional scalar that can produce non constant vacuum energy and associated variations in dark matter. The phenomenology is most interesting when the kinetic term of the additional scalar field is ghost-type, since in this case the dark energy vanishes in the early universe and then grows with time. This constitutes an ''inverse quintessence scenario'', where the universe starts from a zero vacuum energy density state, instead of approaching it in the future.

Authors:
 [1];  [2]
  1. ICRA — International Center for Relativistic Astrophysics, INFN — Istituto Nazionale di Fisica Nucleare, and Dipartimento di Matematica e Informatica, Università degli Studi di Udine, via delle Scienze 206, I-33100 Udine (UD) (Italy)
  2. Department of Physics, Ben-Gurion University of the Negeev, Beer-Sheva 84105 (Israel)
Publication Date:
OSTI Identifier:
22282889
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2013; Journal Issue: 05; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; COSMOLOGICAL MODELS; COUPLING; ENERGY DENSITY; METRICS; NONLUMINOUS MATTER; SCALAR FIELDS; SCALARS; UNIVERSE; VARIATIONS

Citation Formats

Ansoldi, Stefano, and Guendelman, Eduardo I., E-mail: ansoldi@fulbrightmail.org, E-mail: guendel@bgu.ac.il. Unified dark energy-dark matter model with inverse quintessence. United States: N. p., 2013. Web. doi:10.1088/1475-7516/2013/05/036.
Ansoldi, Stefano, & Guendelman, Eduardo I., E-mail: ansoldi@fulbrightmail.org, E-mail: guendel@bgu.ac.il. Unified dark energy-dark matter model with inverse quintessence. United States. doi:10.1088/1475-7516/2013/05/036.
Ansoldi, Stefano, and Guendelman, Eduardo I., E-mail: ansoldi@fulbrightmail.org, E-mail: guendel@bgu.ac.il. 2013. "Unified dark energy-dark matter model with inverse quintessence". United States. doi:10.1088/1475-7516/2013/05/036.
@article{osti_22282889,
title = {Unified dark energy-dark matter model with inverse quintessence},
author = {Ansoldi, Stefano and Guendelman, Eduardo I., E-mail: ansoldi@fulbrightmail.org, E-mail: guendel@bgu.ac.il},
abstractNote = {We consider a model where both dark energy and dark matter originate from the coupling of a scalar field with a non-canonical kinetic term to, both, a metric measure and a non-metric measure. An interacting dark energy/dark matter scenario can be obtained by introducing an additional scalar that can produce non constant vacuum energy and associated variations in dark matter. The phenomenology is most interesting when the kinetic term of the additional scalar field is ghost-type, since in this case the dark energy vanishes in the early universe and then grows with time. This constitutes an ''inverse quintessence scenario'', where the universe starts from a zero vacuum energy density state, instead of approaching it in the future.},
doi = {10.1088/1475-7516/2013/05/036},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 05,
volume = 2013,
place = {United States},
year = 2013,
month = 5
}
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