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The Luminosity Distance, the Equation of State, and the Geometry of the Universe
Open accessAbstract
The second derivative of the luminosity distance with respect to the redshift is written in terms of the deceleration parameter q0. We point out that the third derivative contains the information regarding the sound speed of cosmic matter as well as the curvature of the universe. We restrict physically possible parameter ranges of the coefficients. It is found that there is a relation between the coefficients in a flat universe model with matter such that cs0(1+wx0)=0 (cs0 is the total sound speed of the matter component and wx0=px0/ρx0).
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Cited by
Two new diagnostics of dark energy
Sahni, V., Shafieloo, A., & Starobinsky, A. A. (2008) · Physical Review D · doi:10.1103/physrevd.78.103502 · Cited by 709
Jerk, snap and the cosmological equation of state
Visser, M. (2004) · Classical and Quantum Gravity · doi:10.1088/0264-9381/21/11/006 · Cited by 640
Cosmodynamics: energy conditions, Hubble bounds, density bounds, time and distance bounds
Cattoën, C., & Visser, M. (2008) · Classical and Quantum Gravity · doi:10.1088/0264-9381/25/16/165013 · Cited by 30
Metadata
- Authors
- Chiba, T., & Nakamura, T.
- Venue
- Progress of Theoretical Physics
- Publisher
- Oxford University Press (OUP)
- Published
- 1998-11-01
- Volume
- 100
- Issue
- 5
- Pages
- 1077-1082
- ISSN
- 0033-068X (ISSN-L)
- 1347-4081
- OpenAlex
- W2044504109
- Cited by
- 174
- References
- 0
- FWCI
- 3.02
- Type
- journal article
- Language
- en
- Open access
- green
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- Chiba, T., & Nakamura, T. (1998). The Luminosity Distance, the Equation of State, and the Geometry of the Universe. Progress of Theoretical Physics. https://doi.org/10.1143/ptp.100.1077
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