Title: How Did the First Stars and Galaxies Form?
Speaker: Prof. Avi Loeb
Director, Institute for Theory and Computation
Harvard University
The lecture will overview current theoretical work as well as planned
observational programs concerning the earliest epoch of structure
formation in the Universe. The first galaxies produced UV radiation that
re-ionized hydrogen throughout the Universe. Since the galaxies at
redshifts z>10 represented rare peaks in the underlying density
distribution, they were strongly clustered on scales of up to ~100
comoving Mpc. Therefore, a proper numerical simulation of the reionization
epoch requires a large dynamic range of scales, with a sufficiently large
box size to be representative and a sufficiently fine resolution to
capture the collapse of low-mass galaxies. Theoretical calculations
predict that most of the star formation at z>10 occurred in galaxies that
are more than an order of magnitude fainter than the deepest HST WFC3/IR
survey. Observationally, the distribution of matter will be mapped over
the coming decade through surveys of the first galaxies using the next
generation of large telescopes, as well as through 21-cm tomography of
cosmic hydrogen with new radio observatories. More details can be found in
my new book (which has the same title as this lecture), just published by
Princeton University Press.