The DOI matches its Crossref record; 48 of the 48 references it cites were found in a registry or an index.
Can the dark energy equation-of-state parameter w be less than−1?
Open accessAbstract
Models of dark energy are conveniently characterized by the equation-of-state parameter $w=p/\ensuremath{\rho},$ where $\ensuremath{\rho}$ is the energy density and p is the pressure. Imposing the dominant energy condition, which guarantees stability of the theory, implies that $w>~\ensuremath{-}1.$ Nevertheless, it is conceivable that a well-defined model could (perhaps temporarily) have $w<\ensuremath{-}1 ,$ and indeed such models have been proposed. We study the stability of dynamical models exhibiting $w<\ensuremath{-}1$ by virtue of a negative kinetic term. Although naively unstable, we explore the possibility that these models might be phenomenologically viable if thought of as effective field theories valid only up to a certain momentum cutoff. Under our most optimistic assumptions, we argue that the instability time scale can be greater than the age of the universe, but only if the cutoff is at or below ${10}^{\ensuremath{-}3}\mathrm{eV}.$ We conclude that it is difficult, although not necessarily impossible, to construct viable models of dark energy with $w<\ensuremath{-}1;$ observers should keep an open mind, but the burden is on theorists to demonstrate that any proposed new models are not ruled out by rapid vacuum decay.
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Cites
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Hawking, S. W., & Ellis, G. F. R. (1973) · doi:10.1017/cbo9780511524646 · Cited by 10,624
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Peebles, P. J. E., & Ratra, B. (2003) · Reviews of Modern Physics · doi:10.1103/revmodphys.75.559 · Cited by 5,213
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Cited by
Spergel, D. N., Verde, L., Peiris, H. V., Komatsu, E., Nolta, M. R., Bennett, C. L., Halpern, M., Hinshaw, G., Jarosik, N., Kogut, A., et al. (2003) · The Astrophysical Journal Supplement Series · doi:10.1086/377226 · Cited by 10,976
Phantom Energy: Dark Energy with w < − 1 Causes a Cosmic Doomsday
Caldwell, R. R., Kamionkowski, M., & Weinberg, N. N. (2003) · Physical Review Letters · doi:10.1103/physrevlett.91.071301 · Cited by 2,258
Dark energy constraints from the cosmic age and supernova
Feng, B., Wang, X., & Zhang, X. (2005) · Physics Letters B · doi:10.1016/j.physletb.2004.12.071 · Cited by 1,307
Beyond the cosmological standard model
Joyce, A., Jain, B., Khoury, J., & Trodden, M. (2015) · Physics Reports · doi:10.1016/j.physrep.2014.12.002 · Cited by 1,231
Self-citationGhost Condensation and a Consistent IR Modification of Gravity
Hamed, N. A., Cheng, H. S., Luty, M. A., & Mukohyama, S. (2004) · Journal of High Energy Physics · doi:10.1088/1126-6708/2004/05/074 · Cited by 996
Metadata
- Authors
- Carroll, S. M., Hoffman, M., & Trodden, M.
- Venue
- Physical Review D
- Publisher
- American Physical Society (APS)
- Published
- 2003-07-10
- Volume
- 68
- Issue
- 2
- ISSN
- 0556-2821 (ISSN-L)
- 1089-4918
- OpenAlex
- W2168527615
- Cited by
- 1,251
- References
- 48
- FWCI
- 56.06
- Type
- journal article
- Language
- en
- Open access
- green
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Contains information from the Semantic Scholar Academic Graph Datasets, made available under the ODC Attribution License (ODC-BY 1.0).
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