Browsing Research Articles (Physics) by Author "Ballardini, Mario"
Now showing items 1-10 of 10
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Constraining the neutrino mass using a multitracer combination of two galaxy surveys and cosmic microwave background lensing
Ballardini, Mario; Maartens, Roy (Oxford University Press, 2022)Measuring the total neutrino mass is one of the most exciting opportunities available with next-generation cosmological data sets. We study the possibility of detecting the total neutrino mass using large-scale clustering ... -
Cosmological constraints on post-Newtonian parameters in effectively massless scalar-tensor theories of gravity
Rossi, Massimo; Ballardini, Mario; Braglia, Matteo (2019)We study the cosmological constraints on the variation of Newton’s constant and on post-Newtonian parameters for simple models of the scalar-tensor theory of gravity beyond the extended Jordan-BransDicke theory. We restrict ... -
Energy-momentum tensor and helicity for gauge fields coupled to a pseudoscalar inflaton
Ballardini, Mario (University of the Western Cape, 2019)We study the energy-momentum tensor and helicity of gauge fields coupled through $g \phi F \tilde{F}/4$ to a pseudo-scalar field $\phi$ driving inflation. Under the assumption of a constant time derivative of the background ... -
Larger value for H0 by an evolving gravitational constant
Ballardini, Mario; Braglia, Matteo; Emond, William T. (American Physical Society, 2020)We provide further evidence that a massless cosmological scalar field with a nonminimal coupling to the Ricci curvature of the type M 2 pl ( 1 + ξ σ n / M n pl ) alleviates the existing tension between ... -
Measuring lensing ratios with future cosmological surveys
Ballardini, Mario; Bermejo-Climent, Jos´e Ramón; Finelli, Fabio (American Physical Society, 2020)The ratio between the CMB lensing/galaxy counts and the galaxy shear/galaxy counts cross-correlations combines the information from different cosmological probes to infer cosmographic measurements that are less dependent ... -
New constraints on primordial features from the galaxy two-point correlation function
Moscardini, Lauro; Ballardini, Mario; Marulli, Federico (Physical Review, 2023)Features in the primordial power spectrum represent the imprinted signal in the density perturbations of the physics and evolution of the early Universe. A measurement of such signals will represents the need to go beyond ... -
Non-linear damping of superimposed primordial oscillations on the matter power spectrum in galaxy surveys
Ballardini, Mario; Murgia, Riccardo; Baldi, Marco (IOP Publishing Ltd, 2020)Galaxy surveys are an important probe for superimposed oscillations on the primordial power spectrum of curvature perturbations, which are predicted in several theoretical models of inflation and its alternatives. In order ... -
On the primordial origin of the smoothing excess in the Planck temperature power spectrum in light of LSS data
Ballardini, Mario; Finelli, Fabio (IOP Publishing, 2022)The Planck DR3 measurements of the temperature and polarization anisotropies power spectra of the cosmic microwave background (CMB) show an excess of smoothing of the acoustic peaks with respect to ΛCDM, often quantified ... -
Probing primordial features with the primary CMB
Ballardini, Mario (Elsevier, 2019)We propose to study the imprint of features in the primordial power spectrum with the primary CMB after the subtraction of the reconstructed ISW signal from the observed CMB temperature angular power spectrum. We consider ... -
Scalar-tensor theories of gravity, neutrino physics, and the H0 tension
Ballardini, Mario; Braglia, Matteo; Finelli, Fabio (IOP Publishing, 2020)We use Planck 2018 data to constrain the simplest models of scalar-tensor theories characterized by a coupling to the Ricci scalar of the type F(σ)R with F(σ) = N2 pl + ξσ2 . We update our results with previous Planck ...