Through the Looking Glass: Why the "Cosmic Horizon" is not a horizon

Abstract

The present standard model of cosmology, $\Lambda$CDM, contains some intriguing coincidences. Not only are the dominant contributions to the energy density approximately of the same order at the present epoch, but we note that contrary to the emergence of cosmic acceleration as a recent phenomenon, the time averaged value of the deceleration parameter over the age of the universe is nearly zero. Curious features like these in $\Lambda$CDM give rise to a number of alternate cosmologies being proposed to remove them, including models with an equation of state w = -1/3. In this paper, we examine the validity of some of these alternate models and we also address some persistent misconceptions about the Hubble sphere and the event horizon that lead to erroneous conclusions about cosmology.

Accepted for publication by MNRAS, 6 pages, 3 figures

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Cited by in corpus (20)

• The R_h = ct Universe
• Searching for dark matter - dark energy interactions: going beyond the conformal case
• We do not live in the R_h = c t universe
• The Linear Growth of Structure in the R_h=ct Universe
• The Zero Active Mass Condition in Friedmann-Robertson-Walker Cosmologies
• The Apparent (Gravitational) Horizon in Cosmology
• On Recent Claims Concerning the R_h=ct Universe
• A Test of Cosmological Models using high-z Measurements of H(z)
• Matter Matters: Unphysical Properties of the Rh = ct Universe
• Photon Geodesics in FRW Cosmologies
• How does the Hubble Sphere limit our view of the Universe?
• Primordial Nucleosynthesis in the Rh = ct cosmology: Pouring cold water on the Simmering Universe
• The Gravitational Horizon for a Universe with Phantom Energy
• The dimensionless age of the Universe: a riddle for our time
• Friedmann-Robertson-Walker models do not require zero active mass
• The $R_{\mathrm{h}}=ct$ universe and quintessence
• The Origin of Rest-mass Energy
• Phantom Energy and the Cosmic Horizon: Rh is still not a horizon!
• Puzzling initial conditions in the R_h=ct model
• Is there a Cosmological Basis for E = mc^2?