The Evolution of Our Local Cosmic Domain: Effective Causal Limits

Abstract

The causal limit usually considered in cosmology is the particle horizon, delimiting the possibilities of causal connection in the expanding universe. However it is not a realistic indicator of the effective local limits of important interactions in spacetime. We consider here the matter horizon for the Solar System, that is,the comoving region which has contributed matter to our local physical environment. This lies inside the effective domain of dependence, which (assuming the universe is dominated by dark matter along with baryonic matter and vacuum-energy-like dark energy) consists of those regions that have had a significant active physical influence on this environment through effects such as matter accretion and acoustic waves. It is not determined by the velocity of light c, but by the flow of matter perturbations along their world lines and associated gravitational effects. We emphasize how small a region the perturbations which became our Galaxy occupied, relative to the observable universe -- even relative to the smallest-scale perturbations detectable in the cosmic microwave background radiation. Finally, looking to the future of our cosmic domain, we suggest simple dynamical criteria for determining the present domain of influence and the future matter horizon. The former is the radial distance at which our local region is just now separating from the cosmic expansion. The latter represents the limits of growth of the matter horizon in the far future.

18 pages and 2 figures

References in corpus (1)

• Baryon acoustic signature in the clustering of density maxima

Cited by in corpus (17)

• Does the growth of structure affect our dynamical models of the universe? The averaging, backreaction and fitting problems in cosmology
• Is there proof that backreaction of inhomogeneities is irrelevant in cosmology?
• What is dust? - Physical foundations of the averaging problem in cosmology
• Apparent cosmic acceleration from type Ia supernovae
• Jebsen-Birkhoff theorem and its stability in f(R) gravity
• The Causal Closure of Physics in Real World Contexts
• Astrophysical Black Hole horizons in a cosmological context: Nature and possible consequences on Hawking Radiation
• Cosmological backreaction within the Szekeres model and emergence of spatial curvature
• Birkhoff Theorem and Matter
• Cosmological foundations revisited with Pantheon+
• A dual null formalism for the collapse of fluids in a cosmological background
• Variations on Birkhoff's theorem
• Constructing black hole entropy from gravitational collapse
• Consequences of using a smooth cosmic distance in a lumpy universe: I
• The environment-dependence of the growth of the most massive objects in the Universe
• Cosmic Acceleration from Causal Backreaction in a Smoothly Inhomogeneous Universe
• Cosmic Acceleration and a New Concordance from Causal Backreaction