Open Quantum Dynamics On Lie Group: An Effective Field Theory Approach
Theses
Overview
Overview
abstract
In this thesis, we address construction of effective action for the dissipative systems whose
configuration space coincides with a Lie group. We start by generalizing the classical
system plus reservoir model to the case of position dependent Ohmic dissipation. This is
achieved by coupling the system to a field living in one extra dimension. Then, employing
the Schwinger-Keldysh technique, we construct the general influence functional for a
system on a Lie group which includes the classical contribution and the first quantum
correction within the linear response approximation. Abandoning the linear response
assumption, we generalize the results by requiring the invariance under the dynamical
Kubo-Martin-Schwinger symmetry. This gives us the most general influence functional
with nonlinearly realized symmetry. We explore its systematic reduction to the case of
strictly Ohmic dissipation. Finally, we revisit the field theoretic model of the bath and
show that it produces both the leading and first subleading parts of the most general
influence functional at high temperature.
