Dark energy homogeneity in general relativity: Are we applying it correctly?

2015/05/31 by Didam G. A. Duniya, Didam Duniya
Mathematics · Physics and Astronomy · #Astronomy #Astrophysics #Cosmology #Cosmology and Gravitation Theories #Dark Matter and Cosmic Phenomena #Dark energy #Energy spectrum #Galaxies: Formation, Evolution, Phenomena #Galaxy #General relativity #Homogeneity (statistics) #Homogeneous #Mathematics #Perturbation (astronomy) #Physics #Redshift #Rest frame #Spectral density #Statistical physics #Statistics #Theoretical physics #Theory of relativity #astro-ph.CO #gr-qc

paper · pdf · doi:10.1007/s10714-016-2047-0

published as Gen. Rel. Grav. 48 (2016) 52 · 12 pages, 5 figures. New results added; minor changes. Version accepted by GRG-Journal

arxiv created 2016/03/11 · openalex publication_date 2016/03/30 · arxiv updated 2016/04/05 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05

Abstract

Thus far, there does not appear to be an agreed (or adequate) definition of homogeneous dark energy (DE). This paper seeks to define a valid, adequate homogeneity condition for DE. Firstly, it is shown that as long as w_x ≠ -1, DE must have perturbations. It is then argued, independent of w_x, that a correct definition of homogeneous DE is one whose density perturbation vanishes in comoving gauge: and hence, in the DE rest frame. Using phenomenological DE, the consequence of this approach is then investigated in the observed galaxy power spectrum - with the power spectrum being normalized on small scales, at the present epoch z = 0. It is found that for high magnification bias, relativistic corrections in the galaxy power spectrum are able to distinguish the concordance model from both a homogeneous DE and a clustering DE - on super-horizon scales.

Citations

• Perturbations in dark energy models with evolving speed of sound
• Disentangling non-Gaussianity, bias, and general relativistic effects in the galaxy distribution
• New perspective on the relation between dark energy perturbations and the late-time integrated Sachs-Wolfe effect
• Relativistic corrections and non-Gaussianity in radio continuum surveys
• Roles of dark energy perturbations in the dynamical dark energy models: Can we ignore them?
• Constraining thawing and freezing models with cluster number counts
• What galaxy surveys really measure
• On the growth of linear perturbations
• Imprints of dark energy on cosmic structure formation â I. Realistic quintessence models and the non-linear matter power spectrum
• Impact of dark energy perturbations on the growth index
• Sound speed of scalar field dark energy: Weak effects and large uncertainties
• The effective theory of quintessence: thew< −1 side unveiled
• Accelerating Universes with Scaling Dark Matter
• Falsifying paradigms for cosmic acceleration
• Dynamics of dark energy
• Dispersion of growth of matter perturbations inf(R)gravity
• Cosmological Perturbation Theory