2019

Sweating the small stuff: dwarf galaxies as a testbed for fundamental physics and cosmology

by Dr Coral Wheeler (CalTech)

Pacific/Honolulu
420 (W420)

420

W420

Description

The currently favored cosmological paradigm has been widely successful in predicting the counts, clustering,
colors, morphologies, and evolution of galaxies on large scales. However, fundamental questions remain
unanswered within the model, with perhaps the most glaring being the fundamental nature of dark matter. Clues
to these unknowns may come from the several challenges that have arisen to the model in recent years, most of
which occur at the smallest scales — those of dwarf galaxies (Mstar < 10^9 Msun). These low mass galaxies are
the most dark matter dominated objects in the Universe, and so it is now the smallest scales of galaxy formation
that have the best chance of revealing truths about our overall cosmological framework. I will introduce a suite of
extremely high-resolution cosmological simulations of dwarf galaxies that allow us to probe smaller physical
scales than previously possible in cosmological simulations, and argue that the study of the counts and kinematics
of low-mass galaxies can inform our understanding of the nature of dark matter, and even the properties of the
Universe in its infancy.correlations are poised to become increasingly powerful and will play an important role in
enabling future cosmological surveys to distinguish between possible hints of new physics and systematic errors.