TY  - GEN
Y1  - 2021///
ID  - heidok30183
UR  - https://archiv.ub.uni-heidelberg.de/volltextserver/30183/
AV  - public
A1  - Corell, Lukas
CY  - Heidelberg
N2  - In this work, a framework for the computation of the time evolution of
correlation functions is developed. For that purpose, techniques from the
functional renormalisation group (fRG) are used, with the unique feature of a
temporal regulator. This specific choice of regulator suppresses quantum
fluctuations based on a time scale and yields causal properties for correlation
functions. As a consequence, flow equations can always be integrated
analytically, which in turn allows for the derivation of a one-loop exact
functional relation for the inverse propagator. In addition to this formal
result, the method is applied to the phi^3-theory, where the dynamics of the
propagator is investigated. In this setup, the system is prepared
far-from-equilibrium and the time evolution of the propagator is computed. Even
in the simple truncation that is employed, there are already hints at a
self-similar time evolution.

In a separate part, three-dimensional Yang-Mills theory is examined in
equilibrium. Due to the simpler computation as opposed to non-equilibrium
scenarios, it is possible to investigate this theory in view of different
truncations. This study reveals that truncations have to be chosen carefully in
order to achieve apparent convergence.
TI  - Quantum Dynamics from the Functional Renormalisation Group with a Temporal Regulator
ER  -