Simulating the formation and evolution of galaxies and cosmic structure

我们的宇宙包含了一系列惊人的可见结构，从行星到恒星，再到星系和星系团。我们也可以看到很远的距离，从而回到过去，看到当前结构的早期混沌祖先。最终，在最遥远的地方，我们只看到大爆炸余辉中的小涟漪，它们是所有当前结构的种子。这种进化是如何发生的？这个项目将宇宙放入一台计算机中，让我们可以实验宇宙结构是如何形成、相互作用和进化的；在几小时或几天内，我们就可以模拟140亿年的宇宙历史。

Our universe contains an astonishing array of visible structures ranging in size from planets, to stars, to galaxies and clusters of galaxies. We can also look to great distances, and hence back in time, and see the early, chaotic progenitors of current structure. Eventually, at the furthest distances we see just the small ripples in the afterglow of the Big Bang that are the seeds for all current structure. How did this evolution happen? This project puts the universe into a computer, allowing us to experiment with how cosmic structures form, interact and evolve; in hours or days we can model what has taken 14 billion years of cosmic history. In many respects we now understand the distribution of cosmic structures on the largest scales, tens of millions of light years and greater, but a detailed understanding of galaxies themselves remains elusive. Yet galaxies are the key luminous markers of the universe, and understanding their origins and histories stands as a central goal of late-universe cosmology; this is the focus of my research. Galaxies result from the complex interplay of several processes which we must model. Gravity acts on all matter: invisible dark matter, gas, dust and stars. Gas is subject to hydrodynamic forces. Stars form out of the gaseous inter-stellar medium, energize their surroundings with ionizing radiation and winds during their lives, and, at their deaths, return gas enriched with heavy elements to the inter-stellar medium in violent explosions. We are developing increasingly accurate computer simulations of these processes with the ultimate aim of providing detailed models of galaxy populations and their formation and evolution. The research provides the theoretical counterpart to the wealth of observational data that astronomers are now gathering and anticipating from ground- and space-based observatories. It is a key driver of numerical modelling expertise in Canada and forms part of the internationally recognized Canadian endeavour to uncover our cosmic origins.