I've always been interested in how the universe works on the most fundamental levels as well as in its entirety. By that I've been very keen on studying astrophysics and cosmology just as quantum field theory.
Coming from the theory side I'm looking forward to the developments in multi-messenger astronomy. Especially gravitational wave observatories seem to me as the ideal tool for looking for new physics. In combination with black holes or neutron stars one gets cosmic labs testing our understanding of the world in conditions not reproducible by man-made experiments. This also can shine a light on a central mystery of gravity – dark matter.
In addition to analysing the actual waveforms measured by these detectors, indirect measurements like from the orbital periods of pulsars are useful. This can help getting a complete picture of these systems by looking at systems earlier in their inspiral, where the gravitational radiation is not strong enough jet to be detected directly. Calculating general constraints on f(R) gravity and by that also scalar dark matter can be done with only a modest amount of computational resources. This is made possible by advancements in the field of radio astronomy leading to very precise measurements in recent years amd making this a very promising path to understanding gravity.