Extreme-Mass-Ratio Inspirals (EMRIs), consisting of a stellar-mass compact object spiraling into a massive black hole, are key sources of gravitational waves for space-based detectors like LISA. Due to their precise waveforms, EMRIs offer a unique opportunity to test the nature of massive black holes and explore potential deviations from General Relativity, such as non-Kerr geometries. This...
Gravitational waves from stellar-mass binary black hole mergers can come from different formation environments, such as star clusters, active galactic nuclei (AGN) disks, or isolated binary evolution in the field. Some intrinsic characteristics of the gravitational-wave signal, such as eccentricity, spins and phase shifts, can give clues about formation channels. However, some of these...
The precise determination of the current expansion rate of the Universe, the Hubble constant ($H_0$), remains a central challenge in cosmology. To address the persistent $H_0$ tension and reconcile the discrepant values inferred from observations at different redshifts ($z$), we investigate $𝑓(𝑅)$ modified gravity theories in the Jordan frame. In this context, an additional degree of freedom...
