Evolution of the Deterministic Collapse Barrier of the Field Clusters as a Probe of Cosmology

TL;DR

This study investigates how the evolution of the deterministic collapse barrier of field clusters varies across different cosmologies, revealing its potential as a new probe to distinguish cosmological models beyond traditional methods.

Contribution

It introduces the analysis of the deterministic collapse barrier's evolution in field clusters across multiple cosmologies, highlighting its sensitivity to cosmological parameters and redshift.

Findings

The collapse barrier is higher than the Einstein-de Sitter value at z=0 and converges to it at high redshift.

Different cosmologies show distinct convergence rates and critical redshifts for the collapse barrier.

The evolution of the collapse barrier can differentiate degenerate cosmologies with similar growth factors.

Abstract

The collapse barrier, $\delta_{c}$, of the field clusters located in the low-density environment is deterministic rather than diffusive, unlike that of the wall counterparts located in the superclusters. Analyzing the data from the Mira-Titan simulations for eleven different cosmologies including the standard $\Lambda$CDM cosmology at various redshifts, we investigate the evolution of the deterministic collapse barrier of the field clusters and explore its dependence on the background cosmology. Regardless of the background cosmology, the deterministic $\delta_{c}$ exhibits a universal behavior of having a higher value than the Einstein-de Sitter spherical collapse barrier height of $\delta_{sc}=1.686$, at $z=0$ but gradually converging down to $\delta_{sc}$ as the dominance of dark energy diminishes with the increment of $z$. A significant difference among different cosmologies, however, is found in its convergence rate as well as in the critical redshift $z_{c}$ at which $\delta_{c}=\delta_{sc}$. Showing that the convergence rate and critical redshifts can distinguish even between the degenerate cosmologies which yield almost identical linear growth factor and cluster mass functions, we suggest that the evolution of the deterministic collapse barrier of the field clusters should be a powerful complementary probe of cosmology.