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Title: Screening in perturbative approaches to LSS

Abstract

A specific value for the cosmological constant Λ can account for late-time cosmic acceleration. However, motivated by the so-called cosmological constant problem(s), several alternative mechanisms have been explored. To date, a host of well-studied dynamical dark energy and modified gravity models exists. Going beyond ΛCDM often comes with additional degrees of freedom (dofs). For these to pass existing observational tests, an efficient screening mechanism must be in place. Furthermore, the linear and quasi-linear regimes of structure formation are ideal probes of such dofs and can capture the onset of screening. We propose here a semi-phenomenological “filter” to account for screening dynamics on LSS observables, with special emphasis on Vainshtein-type screening.

Authors:
 [1];  [2]
  1. Stanford Univ., Stanford, CA (United States)
  2. Stanford Univ., Stanford, CA (United States); SLAC National Accelerator Lab., Menlo Park, CA (United States)
Publication Date:
Research Org.:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1414837
Grant/Contract Number:
AC02-76SF00515
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Physics Letters. Section B
Additional Journal Information:
Journal Volume: 773; Journal Issue: C; Journal ID: ISSN 0370-2693
Publisher:
Elsevier
Country of Publication:
United States
Language:
English
Subject:
79 ASTRONOMY AND ASTROPHYSICS

Citation Formats

Fasiello, Matteo, and Vlah, Zvonimir. Screening in perturbative approaches to LSS. United States: N. p., 2017. Web. doi:10.1016/j.physletb.2017.08.032.
Fasiello, Matteo, & Vlah, Zvonimir. Screening in perturbative approaches to LSS. United States. doi:10.1016/j.physletb.2017.08.032.
Fasiello, Matteo, and Vlah, Zvonimir. 2017. "Screening in perturbative approaches to LSS". United States. doi:10.1016/j.physletb.2017.08.032. https://www.osti.gov/servlets/purl/1414837.
@article{osti_1414837,
title = {Screening in perturbative approaches to LSS},
author = {Fasiello, Matteo and Vlah, Zvonimir},
abstractNote = {A specific value for the cosmological constant Λ can account for late-time cosmic acceleration. However, motivated by the so-called cosmological constant problem(s), several alternative mechanisms have been explored. To date, a host of well-studied dynamical dark energy and modified gravity models exists. Going beyond ΛCDM often comes with additional degrees of freedom (dofs). For these to pass existing observational tests, an efficient screening mechanism must be in place. Furthermore, the linear and quasi-linear regimes of structure formation are ideal probes of such dofs and can capture the onset of screening. We propose here a semi-phenomenological “filter” to account for screening dynamics on LSS observables, with special emphasis on Vainshtein-type screening.},
doi = {10.1016/j.physletb.2017.08.032},
journal = {Physics Letters. Section B},
number = C,
volume = 773,
place = {United States},
year = 2017,
month = 8
}

Journal Article:
Free Publicly Available Full Text
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