How Dark is Dark Energy? A Lightcones Comparison Approach

Abstract

We present a geometrical approach that provides a non-perturbative technique, allowing the standard FLRW observer to evaluate a measurable, scale-dependent distance functional between her idealized FLRW past light cone and the actual physical past light cone. From the point of view of the FLRW observer, gathering data from sources at cosmological redshift $\hat{z}$, this functional generates a geometry--structure--growth contribution ${\Omega }_{\Lambda }(\hat{z})$ to the FLRW cosmological constant ${\hat{\Omega }}_{\Lambda }$. This redshift--dependent contribution erodes the interpretation of ${\hat{\Omega }}_{\Lambda }$ as representing constant dark energy. In particular, ${\Omega }_{\Lambda }(\hat{z})$ becomes significantly large at very low $\hat{z}$, where structures dominate the cosmological landscape. At the pivotal galaxy cluster scale, where cosmological expansion decouples from the local gravitation dynamics, we get ${\Omega }_{\Lambda }(\hat{z})/{\hat{\Omega }}_{\Lambda }=\mathcal{O}(1)$, showing that late--epoch structures provide an effective field contribution to the FLRW cosmological constant that is of the same order of magnitude as its assumed value. We prove that ${\Omega }_{\Lambda }(\hat{z})$ is generated by a scale-dependent effective field governed by structure formation and related to the comparison between the idealized FLRW past light cone and the actual physical past light cone. These results are naturally framed in the mainstream FLRW cosmology; they do not require exotic fields and provide a natural setting for analyzing the coincidence problem, leading to an interpretative shift in the current understanding of constant dark energy.

arXiv comment109 pages

References in corpus (47)

• Observational Evidence from Supernovae for an Accelerating Universe and a Cosmological Constant
• Measurements of Omega and Lambda from 42 High-Redshift Supernovae
• Planck 2015 results. XIII. Cosmological parameters
• A Comprehensive Measurement of the Local Value of the Hubble Constant with 1 km/s/Mpc Uncertainty from the Hubble Space Telescope and the SH0ES Team
• The Cosmic Triangle: Revealing the State of the Universe
• Dark Energy Survey Year 3 Results: Cosmological Constraints from Galaxy Clustering and Weak Lensing
• Cosmological Parameters from Observations of Galaxy Clusters
• The Pantheon+ Analysis: The Full Dataset and Light-Curve Release
• Supernova Limits on the Cosmic Equation of State
• A Map of the Universe
• Cosmic homogeneity demonstrated with luminous red galaxies
• Backreaction in late-time cosmology
• Cosmic clocks, cosmic variance and cosmic averages
• The WiggleZ Dark Energy Survey: the transition to large-scale cosmic homogeneity
• Can the Acceleration of Our Universe Be Explained by the Effects of Inhomogeneities?
• A new framework for analyzing the effects of small scale inhomogeneities in cosmology
• Is there proof that backreaction of inhomogeneities is irrelevant in cosmology?
• Light-cone averaging in cosmology: formalism and applications
• The effect of peculiar velocities on supernova cosmology
• Cosmological parameters are dressed
• Is the Universe homogeneous?
• Light-cone averages in a swiss-cheese universe
• Regional averaging and scaling in relativistic cosmology
• Cosmological background solutions and cosmological backreactions
• Hubble flow variance and the cosmic rest frame
• Convex neighborhoods for Lipschitz connections and sprays
• Lensing and caustic effects on cosmological distances
• The Geometry of Small Causal Diamonds
• Multipole decomposition of the general luminosity distance 'Hubble law' -- a new framework for observational cosmology
• Nonlinear relativistic corrections to cosmological distances, redshift and gravitational lensing magnification. II - Derivation
• Bias and scatter in the Hubble diagram from cosmological large-scale structure
• Direct Minkowski Functional analysis of large redshift surveys: a new high--speed code tested on the luminous red galaxy Sloan Digital Sky Survey-DR7 catalogue
• Do we care about the distance to the CMB? Clarifying the impact of second-order lensing
• Examples of backreaction of small scale inhomogeneities in cosmology
• Growth of Cosmic Structure
• A new approach to the propagation of light-like signals in perturbed cosmological backgrounds
• Model-independent analyses of non-Gaussianity in Planck CMB maps using Minkowski Functionals
• Deviation of geodesics in FLRW spacetime geometries
• Caustics of Compensated Spherical Lens Models
• The Geometry of Large Causal Diamonds and the No Hair Property of Asymptotically de-Sitter Spacetimes
• Theoretical and numerical perspectives on cosmic distance averages
• Comparison theorems for causal diamonds
• Towards Cosmography of the Local Universe
• The skewness of the distance-redshift relation in $\Lambda$CDM
• A comparison theorem for cosmological lightcones
• Comment on "Hubble flow variations as a test for inhomogeneous cosmology"
• A Scale-Dependent Distance Functional between Past Light Cones in Cosmology