Cyril tells us about recent work on Chern-Simons gravity and how if it is the correct general model of gravity then parity violation can be generated during inflation in such a way that correlation functions of galaxies measured today could see that parity violation. Given the recent evidence for parity violation in galaxy correlation functions, that is intriguing.

The model also requires parameter values that could produce baryogenesis, so the same physics would end up producing the (observed?) parity violation and the baryon asymmetry in the universe.

Even if the current hints of parity violation turn out to be wrong, future experiments would be sensitive to smaller magnitudes of this effect, meaning the model will be well constrained by the next wave of large scale structure measurements

Cyril: cyril-creque.github.io

Paper: arxiv.org/abs/2303.04815