"Computational Planet, Star and Galaxy Formation: Bridging the Scales"

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Computer simulations enable the astronomer's dream of seeing galaxies, that change so slowly they appear fixed on the sky in the form of beautiful but static nebulae lit by billions of stars, to evolve before their very eyes. When sped up so that millions of years pass in moments galaxies are dynamic places, swirling vortices where stars are constantly being born and explosively dying. We can now artificially generate disk galaxies with delicate spiral patterns of sparkling gas, dust and stars almost identical to those nearby in the sky. The challenge is to take things to the extreme: to model galaxies as they smash together and create giant bursts of new stars and drive material into super-massive black holes themselves the size of small galaxies lurking in the middle of nearly every galaxy in the sky. These mergers are commonplace in the early universe when galaxies were far more violent places, more like storm wracked clouds than spiral disks and saturated with levels of gas, dust and radiation far above what our Milky Way Galaxy experiences today. We can see stars form today in our Milky Way in clouds of gas and dust weighing up to a million Suns. However, to get a correct picture of the early universe we need to understand the process in detail, so that we can know how stars form when the amounts of gas, dust and radiation are much greater or much lower. We are able to create giant clouds filled with twisted filaments compressed from supersonic gas so tenuous it would be called a vacuum on earth. These filaments break up into glowing young stars like pearls on a string just as they do in stellar nurseries on the sky. We follow these studies to the logical extreme -- heavy gas disks containing a new star where planets too can form. We have been able to form exotic extra-solar planetary systems where massive planets much larger than Jupiter orbit at great distances from their stars as observed by Canadian astronomers.