Astronomy on Tap Leiden: Mysteries of the Universe

Subodh Patil: “Does time have a beginning (and does the question even make sense?)“

Subodh is an assistant professor of theoretical physics at Leiden University, working on many different aspects of early universe cosmology. In his talk, Subodh will discuss our current understanding of the question of whether time has a “beginning” and its possible relation to the “origin” of the universe. The quotation marks are not to be fancy, but rather to highlight the fact that these terms have different semantic, philosophical, and scientific definitions which I will try and go over from the perspective of a theoretical cosmologist. Along the way, you’ll get a brief introduction to some of the ideas currently being entertained by cosmologists as to how the observable universe itself may have come about.

Elisa Chisari: “Mapping the dark Universe“

Elisa Chisari a cosmologist based at Utrecht University. Her work focuses on developing and testing models of the large-scale structure of the Universe as seen through galaxies. One of the phenomena she specialises on is that of tides across the Universe. Galaxies change their shapes in response to gravity just like oceanic tides fall and rise. Elisa uses large maps of the sky to probe this and other phenomena – looking for clues about what the Universe is made of. She is heavily involved in preparations for the analysis of upcoming maps of Rubin Observatory – a new facility in Chile. In her talk, Elisa, will discuss the composition of the Universe. Only 5% of the energy of the Universe is in ordinary matter. Where and what is the rest? Join her to learn how maps of light coming from far away can help us answer these questions.