Effective field theory for sub-MeV dark matter direct detection

点击翻译按钮获取中文摘要

Developed a systematic understanding of an important class of effective field theories (EFTs), relevant for condensed matter systems that could provide insight into dark matter scattering. Specifically, these are systems that have spontaneously broken gauge symmetries. A systematic treatment of such EFTs was lacking, even in the more studied relativistic case. The classic and arguably most important example is the Higgs mechanism in the standard model. A complete and systematic understanding of this was achieved using Hilbert series and scattering amplitude techniques that were in turn developed from prior understanding of theories with spontaneously broken global symmetries. This work corrected some of the existing literature on the so-called Higgs Effective Field Theory, which is widely used at the large hadron collider to study the Higgs sector.An interesting possibility was identified and explored, that the effective field theory that was being developed for the detector could also be applied to the dark matter itself. This was elucidated, and found that a class of light dark matter could be well understood using EFT techniques (and resolve some mysteries surrounding small scale anomalies in galaxy and galaxy cluster observations).The framework for understanding quantum effects in EFTs that are relevant to a large universality class of condensed matter systems was further developed, and new 'non-renormalization' theorems which dictate zero is what is termed the anomalous dimension matrix of a theory were discovered.