Precessing black-hole mergers can produce an imbalance between right- and left-handed circularly polarized gravitational waves. According to the Cosmological Principle, such chiral emission should average out to zero across all binary mergers in our Universe in order to preserve mirror-reflection symmetry at very large scales. In this talk, I will show how gravitational-wave astronomy enables...
In the talk, I will introduce a new semianalytical model (SAM) for supermassive black hole (SMBH) growth that departs from traditional EPS-based merger tree methods by directly tracking differential SMBH growth via mergers. I will show that this model reveals a clear preference for heavy SMBH seeds across diverse datasets—including recent JWST observations—except in cases of extremely...
Extreme mass-ratio inspirals (EMRIs) are one of the major sources of gravitational waves (GWs) that will be detected by LISA. Similar to the compact binary mergers detected by current GW detectors, EMRIs can be used as cosmic rulers to probe the expansion of the Universe and our current cosmological paradigm, the LambdaCDM model. Interestingly, modified gravity theories can affect the...
