Determining the equation of state of the expanding Universe: inverse problem in cosmology

1998/10/31 by Takashi Nakamura, Takeshi Chiba · 10 citations
Physics and Astronomy · #Advanced Mathematical Theories and Applications #Cosmology and Gravitation Theories #Relativity and Gravitational Theory #astro-ph #hep-ph

paper · pdf · doi:10.1046/j.1365-8711.1999.02551.x

published as Mon.Not.Roy.Astron.Soc. 306 (1999) 696-700 · 5 pages, accepted for publication in MNRAS

arxiv created 1999/02/15 · openalex publication_date 1999/07/01 · arxiv updated 2009/11/30 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28

Abstract

Even if the luminosity distance as a function of redshift is obtained accurately using, for example, Type Ia supernovae, the equation of state of the Universe cannot be determined uniquely, as it depends on one free parameter Οk0=k/(a02H02), where a0 and H0 are the present scalefactor and the Hubble parameter, respectively. This degeneracy might be resolved if, for example, the time variations of the redshift of quasars are measured as proposed recently by Loeb. Therefore, the equation of state of the Universe (or the metric of the Universe) might be determined in future without any theoretical assumption on the matter content of the Universe.

Citations

• On Massive Neutron Cores
• The Luminosity Distance, the Equation of State, and the Geometry of the Universe
• Observational Evidence from Supernovae for an Accelerating Universe and a Cosmological Constant

Cited by

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• Kinetically driven quintessence
• Particlelike description in quintessential cosmology
• Undulant Universe: Expansion with alternating eras of acceleration and deceleration
• Degeneracy between the dark components resulting from the fact that gravity only measures the total energy-momentum tensor
• Cosmic acceleration data and bulk-brane energy exchange
• Reconstructing k-essence
• The cosmological constant problem and quintessence
• Reconciling dark energy models withf(R)theories
• Cosmic dynamics in the era of Extremely Large Telescopes