QSeminar: Miles Stoudenmire

Speaker: Miles Stoudenmire

Title: New Approaches for Quantum Dynamics: Imaginary and Complex Time

Abstract: Computing dynamical properties of many-body quantum systems is a research frontier, and is hard in worst-case settings. But states with limited energy content can be much easier to evolve and represent: an observation that motivates fictitious evolution contours to extract physical properties, with imaginary time a well-known example. The limited energy content of imaginary time evolved states gives opportunities for large gains in efficiency, and when using stable evolution methods can give speedups of thousands or more. Another more unusual approach is to explore "complex time", mixing real and imaginary time together. Controlled reconstruction strategies allow one to access physical time-dependent correlation functions with much greater efficiency. I will discuss both strategies and current applications