Ordinary Meeting with Alan Chan, ANU [Hybrid Meeting]

Guest Speaker: Alan Chan, Centre for Gravitational Astrophysics, ANU

Title: "Can Active Galactic Nuclei Be Used as Standard Candles to Measure Cosmology?"

Abstract: The quest to understand the universe's expansion and its underlying mechanisms, such as dark energy, has driven astronomers to seek reliable standard candles for measuring cosmological distances in high-redshift environments. While Type Ia supernovae (SNe Ia) have traditionally served this purpose, recent research suggests that Active Galactic Nuclei (AGNs) may also play a crucial role as standard candles. This talk explores the potential of AGNs in cosmological measurements, examining their unique properties, such as luminosity and variability, that could enable precise distance calculations. By investigating AGNs as standard candles, we aim to uncover new pathways in measuring cosmological parameters and refining our cosmic models. Following the five-year report from the Dark Energy Survey (DES) and the Australian Dark Energy Survey(OzDES), we will also discuss why the dark energy equations of state might need some revisions.

Biography: Alan Chan is an astronomer and a Bachelor of Science student in Astronomy and Astrophysics at the Australian National University (ANU), specialising in advanced physics. He works as an Astronomer and Educational Outreach Assistant at the Mount Stromlo Observatory and serves as the President of the ANU Astronomy Society. Alan is also a student of experimental physics at the ANU Centre for Gravitational Astrophysics, where his research focuses on precision measurement techniques for gravitational wave astronomy.

Alan's research interests encompass a broad range of topics in cosmology and astrophysics, including observational cosmology, multi-messenger astronomy, Active Galactic Nuclei (AGNs), supernovae, black holes, dark energy, galaxy formation, and gravitational wave astronomy. Passionate about science communication, Alan regularly presents at public nights and conferences, making complex astronomical concepts accessible and engaging for all.

Affiliations:
Mount Stromlo Observatory, ANU