The Colloquium takes place every Wednesday at 11:15 AM - Warsaw Copernicus Astronomical Centre online by means of Zoom platform. The Colloquium is given in English and chaired by dr Stanisław Bajtlik (bajtlik@camk.edu.pl). People from outside of the Copernicus Center are very welcome to participate. For technical detailes please contact Dr. Stanislaw Bajtlik.
Surajit Kalita (Warsaw University Observatory)
Fast Radio Bursts (FRBs) are millisecond radio transients with high dispersion measures, making them powerful tracers of ionized matter across cosmological distances. In this talk, I present two complementary approaches, Bayesian analysis and machine learning, applied to a set of localized FRBs to rigorously test the consistency of the $\Lambda$CDM model at late cosmic epoch. Our results reveal a redshift-dependent variation in the inferred Hubble constant, a behavior that stands in contradiction to the core postulate standard cosmology. I will further show that this discrepancy can be resolved for alternate cosmological models. These findings suggest a fundamental inadequacy in the standard cosmological framework and necessitate a deeper revision of the theoretical underpinnings of cosmology to resolve the Hubble tension.
Journal Club takes place on Mondays at 11:15 AM in the Seminar Room. The presentation is given in English and is chaired by Journal Club Coordinators. Anyone interested in giving a Journal Club talk is encouraged to contact the email: journalclub(@camk.edu.pl).
Sudhagar Suyamprakasam (NCAC, Warsaw)
He will summarize the LVK collaboration's GWTC-4.0 catalog papers briefly. https://arxiv.org/abs/2508.18080, https://arxiv.org/abs/2508.18082.
