Search Publications
New physics in light of the H0 tension: An alternative view
Vagnozzi, Sunny
The strong discrepancy between local and early-time (inverse distance ladder) estimates of the Hubble constant H0 could be pointing towards new physics beyond the concordance Λ CDM model. Several attempts to address this tension through new physics rely on extended cosmological models, featuring extra free parameters beyond the six Λ CD…
Cosmography in f (Q ) gravity
Wang, Deng; Sahoo, P. K.; Mandal, Sanjay
Cosmography is an ideal tool to investigate the cosmic expansion history of the Universe in a model-independent way. The equations of motion in modified theories of gravity are usually very complicated; cosmography may select practical models without imposing arbitrary choices a priori. We use the model-independent way to derive f (z ) and its der…
Can late dark energy transitions raise the Hubble constant?
Raveri, Marco; Hu, Wayne; Benevento, Giampaolo
Late times dark energy transitions at redshifts z ≪0.1 can raise the predicted value of the Hubble constant to the SH0ES value, 74.03 ±1.42 (km s-1 Mpc-1) or more, while providing an equally good fit as Λ CDM at 67.73 ±0.41 to higher redshift data, in particular from the cosmic microwave background and baryon acoustic oscilla…
Updated constraints on asteroid-mass primordial black holes as dark matter
Profumo, Stefano; Guhathakurta, Puragra; McKinnon, Kevin +3 more
Microlensing of stars places significant constraints on subplanetary-mass compact objects, including primordial black holes, as dark matter candidates. As the lens' Einstein radius in the source plane becomes comparable to the size of the light source, however, source amplification is strongly suppressed, making it challenging to constrain lenses …
Testing interacting dark matter and dark energy model with cosmological data
Chen, Xuelei; Ma, Yin-Zhe; Cheng, Gong +2 more
We investigate the model of dark matter-dark energy (DM-DE) interaction with coupling strength proportional to the multiplication of dark sector densities with different power indices Q =γ ρcαρdβ. We first investigate the modification of the cosmic expansion history, and then further develop the formalis…
Diffusion in unimodular gravity: Analytical solutions, late-time acceleration, and cosmological constraints
Corral, Cristóbal; Cruz, Norman; González, Esteban
Unimodular gravity is an appealing approach to address the cosmological constant problem. In this scenario, the vacuum energy density of quantum fields does not gravitate and the cosmological constant appears merely as an integration constant. Recently, it has been shown that energy diffusion that may arise in quantum gravity and in theories with …