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

Title: Partially acoustic dark matter cosmology and cosmological constraints

Authors:
; ; ;
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
1406399
Grant/Contract Number:
FG02-13ER41958; SC0009924
Resource Type:
Journal Article: Publisher's Accepted Manuscript
Journal Name:
Physical Review D
Additional Journal Information:
Journal Volume: 96; Journal Issue: 10; Related Information: CHORUS Timestamp: 2017-11-01 16:28:39; Journal ID: ISSN 2470-0010
Publisher:
American Physical Society
Country of Publication:
United States
Language:
English

Citation Formats

Raveri, Marco, Hu, Wayne, Hoffman, Timothy, and Wang, Lian-Tao. Partially acoustic dark matter cosmology and cosmological constraints. United States: N. p., 2017. Web. doi:10.1103/PhysRevD.96.103501.
Raveri, Marco, Hu, Wayne, Hoffman, Timothy, & Wang, Lian-Tao. Partially acoustic dark matter cosmology and cosmological constraints. United States. doi:10.1103/PhysRevD.96.103501.
Raveri, Marco, Hu, Wayne, Hoffman, Timothy, and Wang, Lian-Tao. 2017. "Partially acoustic dark matter cosmology and cosmological constraints". United States. doi:10.1103/PhysRevD.96.103501.
@article{osti_1406399,
title = {Partially acoustic dark matter cosmology and cosmological constraints},
author = {Raveri, Marco and Hu, Wayne and Hoffman, Timothy and Wang, Lian-Tao},
abstractNote = {},
doi = {10.1103/PhysRevD.96.103501},
journal = {Physical Review D},
number = 10,
volume = 96,
place = {United States},
year = 2017,
month =
}

Journal Article:
Free Publicly Available Full Text
This content will become publicly available on November 1, 2018
Publisher's Accepted Manuscript

Save / Share:
  • The standard paradigm of collisionless cold dark matter is in tension with measurements on large scales. In particular, the best fit values of the Hubble rate H 0 and the matter density perturbation σ 8 inferred from the cosmic microwave background seem inconsistent with the results from direct measurements. We show that both problems can be solved in a framework in which dark matter consists of two distinct components, a dominant component and a subdominant component. The primary component is cold and collisionless. The secondary component is also cold, but interacts strongly with dark radiation, which itself forms a tightlymore » coupled fluid. The growth of density perturbations in the subdominant component is inhibited by dark acoustic oscillations due to its coupling to the dark radiation, solving the σ 8 problem, while the presence of tightly coupled dark radiation ameliorates the H 0 problem. The subdominant component of dark matter and dark radiation continue to remain in thermal equilibrium until late times, inhibiting the formation of a dark disk. We present an example of a simple model that naturally realizes this scenario in which both constituents of dark matter are thermal WIMPs. Our scenario can be tested by future stage-IV experiments designed to probe the CMB and large scale structure.« less
  • Although there is overwhelming evidence of dark matter from its gravitational interaction, we still do not know its precise gravitational interaction strength or whether it obeys the equivalence principle. Using the latest available cosmological data and working within the framework of ΛCDM, we first update the measurement of the multiplicative factor of cosmology-relevant Newton’s constant over the standard laboratory-based value and find that it is consistent with one. In general relativity, dark matter equivalence principle breaking can be mimicked by a long-range dark matter force mediated by an ultra light scalar field. Using the Planck three year data, we findmore » that the dark matter “fifth-force” strength is constrained to be weaker than 10{sup −4} of the gravitational force. We also introduce a phenomenological, post-Newtonian two-fluid description to explicitly break the equivalence principle by introducing a difference between dark matter inertial and gravitational masses. Depending on the decoupling time of the dark matter and ordinary matter fluids, the ratio of the dark matter gravitational mass to inertial mass is constrained to be unity at the 10{sup −6} level.« less
  • Although there is overwhelming evidence of dark matter from its gravitational interaction, we still do not know its precise gravitational interaction strength or whether it obeys the equivalence principle. Using the latest available cosmological data and working within the framework of ΛCDM, we first update the measurement of the multiplicative factor of cosmology-relevant Newton's constant over the standard laboratory-based value and find that it is consistent with one. In general relativity, dark matter equivalence principle breaking can be mimicked by a long-range dark matter force mediated by an ultra light scalar field. Using the Planck three year data, we findmore » that the dark matter ''fifth-force'' strength is constrained to be weaker than 10{sup −4} of the gravitational force. We also introduce a phenomenological, post-Newtonian two-fluid description to explicitly break the equivalence principle by introducing a difference between dark matter inertial and gravitational masses. Depending on the decoupling time of the dark matter and ordinary matter fluids, the ratio of the dark matter gravitational mass to inertial mass is constrained to be unity at the 10{sup −6} level.« less
  • We set constraints on moduli cosmology from the production of dark matter - radiation and baryon -radiation isocurvature fluctuations through modulus decay, assuming the modulus remains light during inflation. We find that the moduli problem becomes worse at the perturbative level as a significant part of the parameter space m{sub {sigma}} (modulus mass) - {sigma}{sub inf} (modulus vacuum expectation value at the end of inflation) is constrained by the nonobservation of significant isocurvature fluctuations. We discuss in detail the evolution of the modulus vacuum expectation value and perturbations, in particular, the consequences of Hubble scale corrections to the modulus potential,more » and the stochastic motion of the modulus during inflation. We show, in particular, that a high modulus mass scale m{sub {sigma}} > or approx. 100 TeV, which allows the modulus to evade big bang nucleosynthesis constraints is strongly constrained at the perturbative level. We find that generically, solving the moduli problem requires the inflationary scale to be much smaller than 10{sup 13} GeV.« less