This is a talk held during the regular colloquium series (usually Tuesdays at 4pm).
The Gaia mission has provided distance and velocity measurements of over a billion stars in the Milky Way, making it the largest stellar catalog at hand.
There is currently a tension between various measurements of the expansion rate of the universe. I will give a recap of this issue, and talk about how we use the Cosmic Microwave Background, our most distant observation, to infer the local expansion rate of space.
In the past few years, a tension has emerged between the current expansion rate of the universe (H0) and the value predicted by early universe probes under the assumption of a standard LCDM cosmology.
Being complex systems containing vast amounts of gas, dust, and stars, galaxies allow us to study the Universe in great detail. It is inside these systems that stars form, and transform the simplest of elements, hydrogen, into heavy elements essential for life as we know it.
The existence of extragalactic fast radio bursts (FRBs) of sub-millisecond durations, originating at cosmologically significant distances, has been established.
The Milky Way was thought to be dynamically young with a fairly smooth potential dominated by a nearly spherical dark matter halo that has evolved little in the last several billion years.
