skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Dark matter in a bouncing universe

Abstract

We investigate a new scenario of dark matter production in a bouncing universe, in which dark matter was produced completely out of equilibrium in the contracting as well as expanding phase. We explore possibilities of using dark matter as a probe of the bouncing universe, focusing on the relationship between a critical temperature of the bouncing universe and the present relic abundance of dark matter.

Authors:
; ;  [1]
  1. Department of Physics, Nanjing University, 22 Hankou Road, Nanjing, 210093 China (China)
Publication Date:
OSTI Identifier:
22375771
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2014; Journal Issue: 11; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ABUNDANCE; CRITICAL TEMPERATURE; EQUILIBRIUM; NONLUMINOUS MATTER; UNIVERSE

Citation Formats

Cheung, Yeuk-Kwan E., Kang, Jin U, and Li, Changhong, E-mail: cheung@nju.edu.cn, E-mail: jin.u.kang2@gmail.com, E-mail: chellifegood@gmail.com. Dark matter in a bouncing universe. United States: N. p., 2014. Web. doi:10.1088/1475-7516/2014/11/001.
Cheung, Yeuk-Kwan E., Kang, Jin U, & Li, Changhong, E-mail: cheung@nju.edu.cn, E-mail: jin.u.kang2@gmail.com, E-mail: chellifegood@gmail.com. Dark matter in a bouncing universe. United States. doi:10.1088/1475-7516/2014/11/001.
Cheung, Yeuk-Kwan E., Kang, Jin U, and Li, Changhong, E-mail: cheung@nju.edu.cn, E-mail: jin.u.kang2@gmail.com, E-mail: chellifegood@gmail.com. 2014. "Dark matter in a bouncing universe". United States. doi:10.1088/1475-7516/2014/11/001.
@article{osti_22375771,
title = {Dark matter in a bouncing universe},
author = {Cheung, Yeuk-Kwan E. and Kang, Jin U and Li, Changhong, E-mail: cheung@nju.edu.cn, E-mail: jin.u.kang2@gmail.com, E-mail: chellifegood@gmail.com},
abstractNote = {We investigate a new scenario of dark matter production in a bouncing universe, in which dark matter was produced completely out of equilibrium in the contracting as well as expanding phase. We explore possibilities of using dark matter as a probe of the bouncing universe, focusing on the relationship between a critical temperature of the bouncing universe and the present relic abundance of dark matter.},
doi = {10.1088/1475-7516/2014/11/001},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 11,
volume = 2014,
place = {United States},
year = 2014,
month =
}
  • The formation of galactic halos in a flat universe dominated by cold dark matter is investigated. Halos of galactic scale form in abundance only after z of about 3. Most present-day halos had at least two progenitors of similar size at z not less than 1. The typical rotation speed of halos at the present day is only about 10 percent of their rms velocity dispersion. Dark halos are generically triaxial with, perhaps, a slight preference for near-prolate configurations. It is concluded that, if it is correct, the standard idea that galaxies form by condensation of gas with dark halosmore » may actually require a high-density universe in order to be compatible with observation. 44 references.« less
  • Cosmological analysis based on currently available observations are unable to rule out a sizeable coupling among the dark energy and dark matter fluids. We explore a variety of coupled dark matter-dark energy models, which satisfy cosmic microwave background constraints, in light of low redshift and near universe observations. We illustrate the phenomenology of different classes of dark coupling models, paying particular attention in distinguishing between effects that appear only on the expansion history and those that appear in the growth of structure. We find that while a broad class of dark coupling models are effectively models where general relativity (GR)more » is modified — and thus can be probed by a combination of tests for the expansion history and the growth of structure —, there is a class of dark coupling models where gravity is still GR, but the growth of perturbations is, in principle modified. While this effect is small in the specific models we have considered, one should bear in mind that an inconsistency between reconstructed expansion history and growth may not uniquely indicate deviations from GR. Our low redshift constraints arise from cosmic velocities, redshift space distortions and dark matter abundance in galaxy voids. We find that current data constrain the dimensionless coupling to be |ξ| < 0.2, but prospects from forthcoming data are for a significant improvement. Future, precise measurements of the Hubble constant, combined with high-precision constraints on the growth of structure, could provide the key to rule out dark coupling models which survive other tests. We shall exploit as well weak equivalence principle violation arguments, which have the potential to highly disfavour a broad family of coupled models.« less
  • It has been suggested that a COBE-normalized ``standard`` cold dark matter (CDM) universe has too much power on small scales compared to the power spectrum of IRAS galaxies. We present the results of an N-body simulation of such a universe and compare the redshift space {ital P}({ital k}) for dark matter halos to that of the IRAS and CfA galaxies. Over the scales that can be investigated in the simulation, {ital P}({ital k}) for halos with overdensities {delta}{similar_to}250 is in excellent agreement with {ital P}({ital k}) for the IRAS galaxies. {ital P}({ital k}) for halos with overdensities {delta}{similar_to}2000 (a moremore » ``biased`` tracer of the mass than the {delta}{similar_to}250 halos) is in moderately good agreement with {ital P}({ital k}) for the CfA galaxies. Assuming one luminous galaxy per dark matter halo, we do not find an excess small-scale power problem for galaxies in a COBE-normalized standard CDM universe. {copyright} {ital 1995} {ital American} {ital Institute} {ital of} {ital Physics}.« less
  • We provide new constraints on the connection between galaxies in the local Universe, identified by the Sloan Digital Sky Survey (SDSS), and dark matter halos and their constituent substructures in the {Lambda}CDM model using WMAP7 cosmological parameters. Predictions for the abundance and clustering properties of dark matter halos, and the relationship between dark matter hosts and substructures, are based on a high-resolution cosmological simulation, the Bolshoi simulation. We associate galaxies with dark matter halos and subhalos using subhalo abundance matching, and perform a comprehensive analysis which investigates the underlying assumptions of this technique including (a) which halo property is mostmore » closely associated with galaxy stellar masses and luminosities, (b) how much scatter is in this relationship, and (c) how much subhalos can be stripped before their galaxies are destroyed. The models are jointly constrained by new measurements of the projected two-point galaxy clustering and the observed conditional stellar mass function of galaxies in groups. We find that an abundance matching model that associates galaxies with the peak circular velocity of their halos is in good agreement with the data, when scatter of 0.20 {+-} 0.03 dex in stellar mass at a given peak velocity is included. This confirms the theoretical expectation that the stellar mass of galaxies is tightly correlated with the potential wells of their dark matter halos before they are impacted by larger structures. The data put tight constraints on the satellite fraction of galaxies as a function of galaxy stellar mass and on the scatter between halo and galaxy properties, and rule out several alternative abundance matching models that have been considered. This will yield important constraints for galaxy formation models, and also provides encouraging indications that the galaxy - halo connection can be modeled with sufficient fidelity for future precision studies of the dark Universe.« less