Author ORCID Identifier
Year of Publication
Doctor of Philosophy (PhD)
Arts and Sciences
Physics and Astronomy
Dr. Sumit R. Das
The dissertation includes two parts.
In Part I, we study non-equilibrium phenomena in various models associated with global quantum quench. It is known that local quantities, when subjected to global quantum quench across or approaching critical points, exhibit a variety of universal scaling behaviors at various quench rates. To investigate if similar scaling holds for non-local quantities, we consider the scaling behavior of circuit complexity under quantum quench across the critical massless point in Majorana fermion field theory of the one-dimensional integrable transverse field Ising model and find it obeys such scaling. To investigate if similar scaling holds for non-relativistic theories, we test various solvable critical quantum quench protocols in a theory of fermions in a harmonic oscillator potential and find local quantities as well as entanglement entropy obeys different scaling behaviors at different quench rates. We study quantum quench in the c=1 matrix model which is holographically dual to two-dimensional string theory. Unlike higher dimensional holographic setups where quantum quench leads to black holes, the emergent spacetime in this model generically develops cosmological singularities at late times.
In Part II, we expand the proposal that target space entanglement provides a precise notion of entanglement in the bulk gravitational duals of Dp brane theories, which was shown in a gauge fixed formalism. We developed a gauge invariant description of target space entanglement in these theories and derived path integral expressions for the entanglement entropy which can be used in numerical calculations.
Digital Object Identifier (DOI)
The author was supported by Keith B. MacAdam Graduate Excellence Fellowship in Physics and Astronomy, Department of Physics and Astronomy, University of Kentucky, in 2020-2021 academic year. This study was partially supported by National Science Foundation grants NSF/PHY-1521045 (2015-2019) and NSF/PHY-1818878 (2018-2021).
Liu, Sinong, "Topics in Quantum Quench and Entanglement" (2021). Theses and Dissertations--Physics and Astronomy. 85.