Joint ASNSW-NSAS Ordinary Meeting with Geraint Lewis

Members of the North Sydney Astronomical Society and ASNSW are invited for a get-together at Epping and online. Geraint Lewis will be our guest speaker. Geraint last presented for the ASNSW at the 2023 South Pacific Star Party. 

Guest Speaker: Geraint Lewis (University of Sydney)

Title: Heavenly Tensions: Is modern cosmology in crisis?

Abstract: In this talk, I’ll explore the growing tensions in modern cosmology—observational discrepancies that may signal cracks in the standard model. I will start with the Hubble tension, a persistent mismatch between early- and late-universe measurements of the expansion rate, which challenges our understanding of cosmic history. From there, we will examine the cosmological principle —the assumption of large-scale uniformity —and how emerging evidence of dipole anisotropies—directional patterns in the distribution of galaxies—may undermine this foundational idea. I will conclude with a “state of the nation” overview, assessing whether cosmology is facing a genuine crisis or simply entering a new phase of discovery.

Biography: Professor Geraint F. Lewis FRSN FLSW FAIP, Professor of Astrophysics in the Sydney Institute for Astrophysics in the School of Physics of the University of Sydney. Born in OId South Wales, Geraint is an outstanding researcher who focuses on cosmological mysteries. Through exquisite and extensive observations with the world’s largest telescopes, coupled with synthetic universes generated on immense supercomputers, he hunts for the dark side — the dark matter and dark energy that shape the cosmos. He has published extensively in international journals with significant discoveries that confront our ideas on the formation and evolution of galaxies. His passion for cosmology and physics is reflected in his teaching and student supervision and an extensive outreach program that brings the mysteries of the universe to diverse international audiences. In 2021, Geraint was awarded the Astronomical Society of Australia's “David Allen Prize” for exceptional achievement in astronomy communication.