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Fluctuations in sky maps of the galaxy redshifts, dubbed as angular redshift fluctuations (ARF), contain precise information about the growth rate of structures and the nature of gravity in the Universe. Specifically, ARF constrain the combination of cosmological parameters $H/H_0,fsigma_8(z)$, while being an intrinsically tomographic probe and largely insensitive to many observational systematic errors, all this without requiring the assumption of any redshift-to-distance relation under a given fiducial cosmology. We present the first cosmological constraints derived from ARF by using BOSS LOWZ+CMASS DR12 galaxy samples, obtaining 7%-accurate constraints on $H/H_0 fsigma_8(z)$ at more than 20 redshifts over the range $z in [0.26,0.72]$. Our best-fitting value is $10%$ larger, but compatible at the $1.4sigma$ level, than the $Lambda$CDM expectation set by {it Planck} observations of the Cosmic Microwave Background (CMB) radiation. Our tomographic measurements, combined with these CMB data, provides one of the strongest constraints on the gravity index $gamma$, $gamma=0.44^{+0.09}_{-0.07}$, which lies within $2sigma$ from the prediction of General Relativity ($gamma_{rm GR}simeq 0.55$).
It has been suggested that late-universe dark matter decays can alleviate the tension between measurements of $H_0$ in the local universe and its value inferred from cosmic microwave background fluctuations. Decaying dark matter can potentially accou
We investigate constraints on scalar dark matter (DM) by analyzing the Lyman-alpha forest, which probes structure formation at medium and small scales, and also by studying its cosmological consequences at high and low redshift. For scalar DM that co
We place limits on semiclassical fluctuations that might be present in the primordial perturbation spectrum. These can arise if some signatures of pre-inflationary features survive the expansion, or could be created by whatever mechanism ends inflati
Dark energy may be the first sign of new fundamental physics in the Universe, taking either a physical form or revealing a correction to Einsteinian gravity. Weak gravitational lensing and galaxy peculiar velocities provide complementary probes of Ge
We use the galaxy angular power spectrum at $zsim0.5-1.2$ from the Canada-France-Hawaii-Telescope Legacy Survey Wide fields (CFHTLS-Wide) to constrain separately the total neutrino mass $sum{m_ u}$ and the effective number of neutrino species $N_{rm{