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Title: Observational Bounds on Cosmic Doomsday

Abstract

Recently it was found, in a broad class of models, that the dark energy density may change its sign during the evolution of the universe. This may lead to a global collapse of the universe within the time t{sub c} {approx} 10{sup 10}-10{sup 11} years. Our goal is to find what bounds on the future lifetime of the universe can be placed by the next generation of cosmological observations. As an example, we investigate the simplest model of dark energy with a linear potential V({phi}) = V{sub 0}(1 + {alpha}{phi}). This model can describe the present stage of acceleration of the universe if {alpha} is small enough. However, eventually the field {phi} rolls down, V({phi}) becomes negative, and the universe collapses. The existing observational data indicate that the universe described by this model will collapse not earlier than t{sub c} {approx_equal} 10 billion years from the present moment. We show that the data from SNAP and Planck satellites may extend the bound on the ''doomsday'' time to tc 40 billion years at the 95% confidence level.

Authors:
Publication Date:
Research Org.:
Stanford Linear Accelerator Center, Menlo Park, CA (US)
Sponsoring Org.:
USDOE Office of Science (US)
OSTI Identifier:
813287
Report Number(s):
SLAC-PUB-10032
TRN: US200316%%33
DOE Contract Number:
AC03-76SF00515
Resource Type:
Technical Report
Resource Relation:
Other Information: PBD: 11 Jul 2003
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; NONLUMINOUS MATTER; ENERGY DENSITY; LIFETIME; COSMOLOGICAL MODELS; GALACTIC EVOLUTION

Citation Formats

Shmakova, Marina. Observational Bounds on Cosmic Doomsday. United States: N. p., 2003. Web. doi:10.2172/813287.
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Shmakova, Marina. Observational Bounds on Cosmic Doomsday. United States. doi:10.2172/813287.
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Shmakova, Marina. Fri . "Observational Bounds on Cosmic Doomsday". United States. doi:10.2172/813287. https://www.osti.gov/servlets/purl/813287.
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@article{osti_813287,
title = {Observational Bounds on Cosmic Doomsday},
author = {Shmakova, Marina},
abstractNote = {Recently it was found, in a broad class of models, that the dark energy density may change its sign during the evolution of the universe. This may lead to a global collapse of the universe within the time t{sub c} {approx} 10{sup 10}-10{sup 11} years. Our goal is to find what bounds on the future lifetime of the universe can be placed by the next generation of cosmological observations. As an example, we investigate the simplest model of dark energy with a linear potential V({phi}) = V{sub 0}(1 + {alpha}{phi}). This model can describe the present stage of acceleration of the universe if {alpha} is small enough. However, eventually the field {phi} rolls down, V({phi}) becomes negative, and the universe collapses. The existing observational data indicate that the universe described by this model will collapse not earlier than t{sub c} {approx_equal} 10 billion years from the present moment. We show that the data from SNAP and Planck satellites may extend the bound on the ''doomsday'' time to tc 40 billion years at the 95% confidence level.},
doi = {10.2172/813287},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Fri Jul 11 00:00:00 EDT 2003},
month = {Fri Jul 11 00:00:00 EDT 2003}
}
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DOI:  10.2172/813287
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