Search Publications
Planck data versus large scale structure: Methods to quantify discordance
Battye, Richard A.; Moss, Adam; Charnock, Tom
Discordance in the Λ cold dark matter cosmological model can be seen by comparing parameters constrained by cosmic microwave background (CMB) measurements to those inferred by probes of large scale structure. Recent improvements in observations, including final data releases from both Planck and SDSS-III BOSS, as well as improved astrophysical unc…
Multitracer CMB delensing maps from Planck and WISE data
Sherwin, Blake D.; Hill, J. Colin; Yu, Byeonghee
Delensing, the removal of the limiting lensing B -mode background, is crucial for the success of future cosmic microwave background (CMB) surveys in constraining inflationary gravitational waves (IGWs). In recent work, delensing with large-scale structure tracers has emerged as a promising method both for improving constraints on IGWs and for test…
Capacitive sensing of test mass motion with nanometer precision over millimeter-wide sensing gaps for space-borne gravitational reference sensors
Mendes, L.; Madden, S.; Russano, G. +100 more
We report on the performance of the capacitive gap-sensing system of the Gravitational Reference Sensor on board the LISA Pathfinder spacecraft. From in-flight measurements, the system has demonstrated a performance, down to 1 mHz, that is ranging between 0.7 and 1.8 aF Hz-1 /2 . That translates into a sensing noise of the test mass mot…
Hamilton-Jacobi formalism to warm inflationary scenario
Sayar, K.; Mohammadi, A.; Akhtari, L. +1 more
The Hamilton-Jacobi formalism as a powerful method is being utilized to reconsider the warm inflationary scenario, where the scalar field as the main component driving inflation interacts with other fields. Separating the context into strong and weak dissipative regimes, the goal is followed for two popular functions of Γ . Applying slow-rolling a…
Changing the Bayesian prior: Absolute neutrino mass constraints in nonlocal gravity*
Dirian, Yves
Prior change is discussed in observational constraints studies of nonlocally modified gravity, where a model characterized by a modification of the form ∼m2R □-2R to the Einstein-Hilbert action was compared against the base Λ CDM one in a Bayesian way. It was found that the competing modified gravity model is significantly di…
Impact of theoretical priors in cosmological analyses: The case of single field quintessence
Peirone, Simone; Raveri, Marco; Silvestri, Alessandra +1 more
We investigate the impact of general conditions of theoretical stability and cosmological viability on dynamical dark energy models. As a powerful example, we study whether minimally coupled, single field quintessence models that are safe from ghost instabilities, can source the Chevallier-Polarski-Linder (CPL) expansion history recently shown to …
Distinguishing between neutrinos and time-varying dark energy through cosmic time
Calabrese, Erminia; Alonso, David; Lorenz, Christiane S.
We study the correlations between parameters characterizing neutrino physics and the evolution of dark energy. Using a fluid approach, we show that time-varying dark energy models exhibit degeneracies with the cosmic neutrino background over extended periods of the cosmic history, leading to a degraded estimation of the total mass and number of sp…
Simulated forecasts for primordial B -mode searches in ground-based experiments
Dunkley, Joanna; Næss, Sigurd; Alonso, David +1 more
Detecting the imprint of inflationary gravitational waves on the B -mode polarization of the cosmic microwave background (CMB) is one of the main science cases for current and next-generation CMB experiments. In this work we explore some of the challenges that ground-based facilities will have to face in order to carry out this measurement in the …
Next non-Gaussianity frontier: What can a measurement with σ (fNL)≲1 tell us about multifield inflation?
Doré, Olivier; de Putter, Roland; Gleyzes, Jérôme
Future galaxy surveys promise to probe local primordial non-Gaussianity at unprecedented precision, σ (fNL)≲1 . We study the implications for multifield inflation by considering spectator models, where inflation is driven by the inflaton field, but the primordial perturbations are (partially) generated by a second, spectator field. We p…
Relic gravitational waves from quintessential inflation
Myrzakulov, R.; Sami, M.; Ahmad, Safia
We study relic gravitational waves in the paradigm of quintessential inflation. In this framework, irrespective of the underlying model, inflation is followed by the kinetic regime. Thereafter, the field energy density remains subdominant before the onset of acceleration. We carry out model-independent analysis to obtain the temperature at the end…