From excursion sets to today: a random walk through the history of cosmological simulations

It has been almost 33 years since the publication of the seminar article by Dick Bond titled "Excursion Set Mass Functions for Hierarchical Gaussian Fluctuations." This piece set the foundation for our understanding of dark matter halo abundances, which serves as a keystone for galaxy formation theory. In this talk I will guide the audience through a historical random walk connecting this seminar work to today. I will first focus on the power and limitations of excursion set theory, which helped ignite the emergence of cosmological N-body simulations. Then I will describe the development of semi-analytic models and hydrodynamic cosmological simulations. I will follow with a discussion of next-generation simulations capable of capturing the multi-phase turbulent structure of the interstellar medium, and connections to controversies raised by recent JWST observations. I will conclude with future prospects in the cosmological simulation realm, including runs capable of resolving individual stars -- in the context of the forthcoming US Extremely Large Telescope program.