Nuclear Physics & RIKEN Theory Seminar

Learning about the QCD phase diagram at low temperatures using lattice QCD has proven highly difficult due to the well-known sign problem, which manifests itself as a noise problem in canonical formalisms. In this talk, I will show that noise in lattice calculations tends to fall into two classes, corresponding to symmetric and long-tailed distributions, respectively, based on the physics of the system under study. I will present a lattice study of unitary fermions, a simplified system which we can use to understand the noise problem for long-tailed distributions, and show that understanding the distribution allows us to both tame the noise problem and extract previously unknown physical results for systems of bosons at unitarity, known as Efimov states, from the distribution itself. Finally, I will discuss the possible applicability of these findings to lattice QCD calculations.