Cosmologists at Perimeter Institute seek to help pin down the constituents and history of our universe, and the rules governing its origin and evolution. Many of the most interesting clues about physics beyond the standard model (e.g., dark matter, dark energy, the matter/anti-matter asymmetry, and the spectrum of primordial density perturbations], come from cosmological observations, and cosmological observations are often the best way to test or constrain a proposed modification of the laws of nature, since such observations can probe length scales, time scales, and energy scales that are beyond the reach of terrestrial laboratories.
The initial conditions of our Universe can be summarized on a single sheet of paper. Yet the Universe is full of complex structures today, such as stars, galaxies and groups of galaxies. I will describe how complexity emerged in the form of the first stars out of the simple initial state of the Universe at early cosmic times. The future of the Universe is even more surprising. Over the past decade it was realized that the cosmic expansion has been accelerating. If this accelerated expansion will continue into the future, then within a hundred billion years there will be no galaxies left for us to observe within the cosmic horizon except one: the merger product between our own Milky Way galaxy and its nearest neighbor, the Andromeda galaxy.