Constraints on Cosmology and Gravity from the Dynamics of Voids.
The Universe is mostly composed of large and relatively empty domains known as cosmic voids, whereas its matter content is predominantly distributed along their boundaries. The remaining material inside them, either dark or luminous matter, is attracted to these boundaries and causes voids to expand faster and to grow emptier over time. Using the distribution of galaxies centered on voids identified in the Sloan Digital Sky Survey and adopting minimal assumptions on the statistical motion of these galaxies, we constrain the average matter content Ω_{m}=0.281±0.031 in the Universe today, as well as the linear growth rate of structure f/b=0.417±0.089 at median redshift z[over ¯]=0.57, where b is the galaxy bias (68% C.L.). These values originate from a percent-level measurement of the anisotropic distortion in the void-galaxy cross-correlation function, ϵ=1.003±0.012, and are robust to consistency tests with bootstraps of the data and simulated mock catalogs within an additional systematic uncertainty of half that size. They surpass (and are complementary to) existing constraints by unlocking cosmological information on smaller scales through an accurate model of nonlinear clustering and dynamics in void environments. As such, our analysis furnishes a powerful probe of deviations from Einstein's general relativity in the low-density regime which has largely remained untested so far. We find no evidence for such deviations in the data at hand.
Universitäts-Sternwarte München, Fakultät für Physik, Ludwig-Maximilians-Universität München, Scheinerstrasse 1, D-81679 München, Germany.
Nico
N
Hamaus
CPPM, CNRS/IN2P3, UMR 7346, Aix Marseille Université, 163 avenue de Luminy, F-13288 Marseille, France.|Institut d'Astrophysique de Paris, UMR 7095, Sorbonne Universités, UPMC Université Paris 06, 98 bis boulevard Arago, F-75014, Paris, France.|CNRS, UMR 7095, Institut d'Astrophysique de Paris, 98 bis boulevard Arago, F-75014 Paris, France.
Alice
A
Pisani
Center for Cosmology and AstroParticle Physics, The Ohio State University, 191 West Woodruff Avenue, Columbus, Ohio 43210, USA.|INFN-National Institute for Nuclear Physics, via Valerio 2, I-34127 Trieste, Italy.|INAF-Osservatorio Astronomico di Trieste, via Tiepolo 11, I-34143 Trieste, Italy.
P M
PM
Sutter
Institut d'Astrophysique de Paris, UMR 7095, Sorbonne Universités, UPMC Université Paris 06, 98 bis boulevard Arago, F-75014, Paris, France.|CNRS, UMR 7095, Institut d'Astrophysique de Paris, 98 bis boulevard Arago, F-75014 Paris, France.
Guilhem
G
Lavaux
CPPM, CNRS/IN2P3, UMR 7346, Aix Marseille Université, 163 avenue de Luminy, F-13288 Marseille, France.
Stéphanie
S
Escoffier
Institut d'Astrophysique de Paris, UMR 7095, Sorbonne Universités, UPMC Université Paris 06, 98 bis boulevard Arago, F-75014, Paris, France.|CNRS, UMR 7095, Institut d'Astrophysique de Paris, 98 bis boulevard Arago, F-75014 Paris, France.|Departments of Physics and Astronomy, University of Illinois at Urbana-Champaign, 1110 West Green Street, Urbana, Illinois 61801, USA.
Benjamin D
BD
Wandelt
Universitäts-Sternwarte München, Fakultät für Physik, Ludwig-Maximilians-Universität München, Scheinerstrasse 1, D-81679 München, Germany.|Max Planck Institute for Extraterrestrial Physics, Giessenbachstrasse 1, D-85748 Garching, Germany.|Excellence Cluster Universe, Bolzmannstrasse 2, D-85748 Garching, Germany.
Jochen
J
Weller