« Confronting the Cosmological Principle: How secure are the foundations of the cosmos? »
I will present our recent work using quasars and radio galaxies to test the cosmological principle—the foundation of modern cosmology. While this principle states the universe is isotropic and homogeneous, the Cosmic Microwave Background (CMB) reveals a pronounced dipole, interpreted as our motion relative to the Hubble flow. This motion should appear in other cosmological observations, yet recent studies show significant tension with expectations, challenging the principle itself. I find a CMB-aligned dipole using large-scale surveys and Bayesian methods, but its amplitude remains inconsistent with predictions, raising fundamental questions about our cosmological framework.