Cosmological constant problem and renormalized vacuum energy density in curved background
Abstract
The current vacuum energy density observed as dark energy ρ{sub dark}≅ 2.5×10{sup −47} GeV{sup 4} is unacceptably small compared with any other scales. Therefore, we encounter serious finetuning problem and theoretical difficulty to derive the dark energy. However, the theoretically attractive scenario has been proposed and discussed in literature: in terms of the renormalizationgroup (RG) running of the cosmological constant, the vacuum energy density can be expressed as ρ{sub vacuum}≅ m {sup 2} H {sup 2} where m is the mass of the scalar field and rather dynamical in curved spacetime. However, there has been no rigorous proof to derive this expression and there are some criticisms about the physical interpretation of the RG running cosmological constant. In the present paper, we revisit the RG running effects of the cosmological constant and investigate the renormalized vacuum energy density in curved spacetime. We demonstrate that the vacuum energy density described by ρ{sub vacuum}≅ m {sup 2} H {sup 2} appears as quantum effects of the curved background rather than the running effects of cosmological constant. Comparing to cosmological observational data, we obtain an upper bound on the mass of the scalar fields to be smaller than the Planck mass, m ∼<more »
 Authors:
 Theory Center, IPNS, KEK, Tsukuba 3050801, Ibaraki (Japan)
 The Graduate University of Advanced Studies (Sokendai), Tsukuba 3050801, Ibaraki (Japan)
 Publication Date:
 OSTI Identifier:
 22676182
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2017; Journal Issue: 06; Other Information: Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; COMPARATIVE EVALUATIONS; COSMOLOGICAL CONSTANT; ENERGY DENSITY; GEV RANGE; MASS; NONLUMINOUS MATTER; RENORMALIZATION; SCALAR FIELDS; SPACETIME
Citation Formats
Kohri, Kazunori, and Matsui, Hiroki, Email: kohri@post.kek.jp, Email: matshiro@post.kek.jp. Cosmological constant problem and renormalized vacuum energy density in curved background. United States: N. p., 2017.
Web. doi:10.1088/14757516/2017/06/006.
Kohri, Kazunori, & Matsui, Hiroki, Email: kohri@post.kek.jp, Email: matshiro@post.kek.jp. Cosmological constant problem and renormalized vacuum energy density in curved background. United States. doi:10.1088/14757516/2017/06/006.
Kohri, Kazunori, and Matsui, Hiroki, Email: kohri@post.kek.jp, Email: matshiro@post.kek.jp. Thu .
"Cosmological constant problem and renormalized vacuum energy density in curved background". United States.
doi:10.1088/14757516/2017/06/006.
@article{osti_22676182,
title = {Cosmological constant problem and renormalized vacuum energy density in curved background},
author = {Kohri, Kazunori and Matsui, Hiroki, Email: kohri@post.kek.jp, Email: matshiro@post.kek.jp},
abstractNote = {The current vacuum energy density observed as dark energy ρ{sub dark}≅ 2.5×10{sup −47} GeV{sup 4} is unacceptably small compared with any other scales. Therefore, we encounter serious finetuning problem and theoretical difficulty to derive the dark energy. However, the theoretically attractive scenario has been proposed and discussed in literature: in terms of the renormalizationgroup (RG) running of the cosmological constant, the vacuum energy density can be expressed as ρ{sub vacuum}≅ m {sup 2} H {sup 2} where m is the mass of the scalar field and rather dynamical in curved spacetime. However, there has been no rigorous proof to derive this expression and there are some criticisms about the physical interpretation of the RG running cosmological constant. In the present paper, we revisit the RG running effects of the cosmological constant and investigate the renormalized vacuum energy density in curved spacetime. We demonstrate that the vacuum energy density described by ρ{sub vacuum}≅ m {sup 2} H {sup 2} appears as quantum effects of the curved background rather than the running effects of cosmological constant. Comparing to cosmological observational data, we obtain an upper bound on the mass of the scalar fields to be smaller than the Planck mass, m ∼< M {sub Pl}.},
doi = {10.1088/14757516/2017/06/006},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 06,
volume = 2017,
place = {United States},
year = {Thu Jun 01 00:00:00 EDT 2017},
month = {Thu Jun 01 00:00:00 EDT 2017}
}

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