Search Publications
Updated tomographic analysis of the integrated Sachs-Wolfe effect and implications for dark energy
Bilicki, Maciej; Lesgourgues, Julien; Cuoco, Alessandro +1 more
We derive updated constraints on the integrated Sachs-Wolfe (ISW) effect through cross-correlation of the cosmic microwave background with galaxy surveys. We improve with respect to similar previous analyses in several ways. First, we use the most recent versions of extragalactic object catalogs, SDSS DR12 photometric redshift (photo-z ) and 2MASS…
MICROSCOPE limits for new long-range forces and implications for unified theories
Fayet, Pierre
Many theories beyond the standard model involve an extra U (1 ) gauge group. The resulting gauge boson U , in general mixed with the Z and the photon, may be massless or very light and very weakly coupled. It may be viewed as a generalized dark photon interacting with matter through a linear combination [ɛQQ +ɛBB +ɛL
Do current cosmological observations rule out all covariant Galileons?
Peirone, Simone; Frusciante, Noemi; Hu, Bin +2 more
We revisit the cosmology of covariant Galileon gravity in view of the most recent cosmological data sets, including weak lensing. As a higher derivative theory, covariant Galileon models do not have a Λ CDM limit and predict a very different structure formation pattern compared with the standard Λ CDM scenario. Previous cosmological analyses sugge…
Two-halo term in stacked thermal Sunyaev-Zel'dovich measurements: Implications for self-similarity
Hill, J. Colin; Jain, Bhuvnesh; Greco, Johnny P. +2 more
The relation between the mass and integrated electron pressure of galaxy group and cluster halos can be probed by stacking maps of the thermal Sunyaev-Zel'dovich (tSZ) effect. Perhaps surprisingly, recent observational results have indicated that the scaling relation between integrated pressure and mass follows the prediction of simple, self-simil…
Price of shifting the Hubble constant
Evslin, Jarah; Ruchika; Sen, Anjan A.
An anisotropic measurement of the baryon acoustic oscillation (BAO) feature fixes the product of the Hubble constant and the acoustic scale H0rd. Therefore, regardless of the dark energy dynamics, to accommodate a higher value of H0 one needs a lower rd and so necessarily a modification of early time cos…
Model independent inference of the expansion history and implications for the growth of structure
Joudaki, Shahab; Kirkby, David; Kaplinghat, Manoj +1 more
We model the expansion history of the Universe as a Gaussian process and find constraints on the dark energy density and its low-redshift evolution using distances inferred from the Luminous Red Galaxy and Lyman-alpha data sets of the Baryon Oscillation Spectroscopic Survey, supernova data from the Joint Light-Curve Analysis sample, cosmic microwa…
Experimental results from the ST7 mission on LISA Pathfinder
Mendes, L.; Anderson, J.; Cooper, M. +146 more
The Space Technology 7 Disturbance Reduction System (ST7-DRS) is a NASA technology demonstration payload that operated from January 2016 through July 2017 on the European Space Agency's (ESA) LISA Pathfinder spacecraft. The joint goal of the NASA and ESA missions was to validate key technologies for a future space-based gravitational wave observat…
Gravitational waves and the polarizations in Hořava gravity after GW170817
Gong, Yungui; Hou, Shaoqi; Papantonopoulos, Eleftherios +1 more
The gravitational waves of Hořava gravity, their polarization states, and their possible observational signatures are discussed. Using the gauge-invariant variable formalism, we find the three polarization modes in Hořava gravity excited by the three physical degrees of freedom contained in this theory. In particular, the scalar degree of freedom …
Tensions between direct measurements of the lens power spectrum from Planck data
Hu, Wayne; Motloch, Pavel
We apply a recently developed method to directly measure the gravitational lensing power spectrum from CMB power spectra to the Planck satellite data. This method allows us to analyze the tension between the temperature power spectrum and lens reconstruction in a model-independent way. Even when allowing for arbitrary variations in the lensing pow…
Cosmological constraints and comparison of viable f (R ) models
Nesseris, Savvas; Pérez-Romero, Judit
In this paper we present cosmological constraints on several well-known f (R ) models, but also on a new class of models that are variants of the Hu-Sawicki one of the form f (R )=R -2/Λ 1 +b y (R ,Λ ) , that interpolate between the cosmological constant model and a matter dominated universe for different values of the parameter b , which is usual…