LOFAR & SKA polarized source catalogues as probes of dark sectorsRecording

by Fumihiro Naokawa (University of Tokio (Japan))

Wednesday Oct 8, 2025, 4:00 PM → 5:30 PM Europe/Madrid

00.303.0 - Aula 13 (Facultad de Ciencias Físicas)

Recent analyses of the Cosmic Microwave Background (CMB) polarization have reported hints of "cosmic birefringence" - a uniform rotation of the polarization angle of CMB photons (e.g. Komatsu 2020). If confirmed, this signal would provide strong evidence for new physics, such as axion-like particles or dark-sectors (e.g. Fujita et al. 2021). However, current CMB measurements still face challenges, including systematic uncertainties and difficulties in probing the redshift evolution of the effect. In this context, the polarization of radio galaxies and the morphology of their jets offer independent and complementary probes of cosmic birefringence (e.g. Carroll et al. 1990). Recent and upcoming large catalogues of such sources by LOFAR or SKA (e.g. O'Sullivan et al. 2023) have the potential to reveal the dark sectors of the universe through cosmic birefringence (Naokawa 2025).

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