Stellar population synthesis models are at the heart of essentially all inference about galaxies.
The existence of extragalactic fast radio bursts (FRBs) of sub-millisecond durations, originating at cosmologically significant distances, has been established.
The recent tension between early- and late-Universe measurements of the Hubble constant highlights the necessity for independent and precise probes such as the time-delay cosmography.
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.