Zobrazeno 1 - 10
of 70
pro vyhledávání: '"Giani, Leonardo"'
We propose a two parameters extension of the flat $\Lambda$CDM model to capture the impact of matter inhomogeneities on the background evolution of the Universe. Non virialized but non-linearly evolving overdense and underdense regions, whose abundan
Externí odkaz:
http://arxiv.org/abs/2410.15295
Autor:
Filzinger, Melina, Caddell, Ashlee R., Jani, Dhruv, Steinel, Martin, Giani, Leonardo, Huntemann, Nils, Roberts, Benjamin M.
We devise and demonstrate a method to search for non-gravitational couplings of ultralight dark matter to standard model particles using space-time separated atomic clocks and cavity-stabilized lasers. By making use of space-time separated sensors, w
Externí odkaz:
http://arxiv.org/abs/2312.13723
Autor:
Frion, Emmanuel, Camarena, David, Giani, Leonardo, Miranda, Tays, Bertacca, Daniele, Marra, Valerio, Piattella, Oliver F.
Publikováno v:
The Open Journal of Astrophysics, Volume 7, 2024
We consider cosmological models in which Dark Matter (DM) and Dark Energy (DE) are described by a single component, dubbed Unified Dark Matter (UDM) models, in which the DE-like part can have an equation state $<-1$ at late times without violating th
Externí odkaz:
http://arxiv.org/abs/2307.06320
How does the appearance of a strongly lensed system change if a gravitational wave is produced by the lens? In this work we address this question by considering a supermassive black hole binary at the center of the lens emitting gravitational waves p
Externí odkaz:
http://arxiv.org/abs/2302.10472
We investigate the cosmological implications of an effective gravitational action, inspired by Sakharov's idea of induced gravity, containing non-local contributions from the operator $\left(\Box +\beta \right)^{-1} R$. The $\beta$ term is a novel fe
Externí odkaz:
http://arxiv.org/abs/2302.06762
Autor:
Giani, Leonardo, Howlett, Cullan, Ruggeri, Rossana, Bianchini, Federico, Said, Khaled, Davis, Tamara M.
We study, for the first time, the cross correlation between the angular distribution of radial peculiar velocities (PV) and the lensing convergence of cosmic microwave background (CMB) photons. We derive theoretical expectations for the signal and it
Externí odkaz:
http://arxiv.org/abs/2301.08381
Autor:
Giani, Leonardo, Davis, Tamara M.
If Dark Matter halos possess the gravitational equivalent of an intrinsic magnetic spin, a formal analogy exists between the low redshift behaviour of the Cosmic Web in a flat FLRW background, and a crystal of spins submerged in a thermal reservoir w
Externí odkaz:
http://arxiv.org/abs/2205.05235
We investigate a model of gravitational collapse of matter inhomogeneities where the latter are modelled as Bianchi type IX (BIX) spacetimes. We found that this model contains, as limiting cases, both the standard spherical collapse model and the Zel
Externí odkaz:
http://arxiv.org/abs/2112.01869
The apparent angular size of the shadow of a black hole in an expanding Universe is redshift-dependent. Since cosmological redshifts change with time - known as the redshift drift - all redshift-dependent quantities acquire a time-dependence, and a f
Externí odkaz:
http://arxiv.org/abs/2107.13536
We study how the evolution of a Dark Energy Quintessence fluid is modified by the presence of a matter inhomogeneity. To do so, we study linear perturbations of a flat FLRW background containing dust and a slowly rolling scalar field. Under the assum
Externí odkaz:
http://arxiv.org/abs/2102.11735