1.1k citations · 10.2k across the 101 of their papers we have counts for
103 papers
Variational Solution of Non-Hermitian Quantum Field Theory in Two Dimensions
Paul Romatschke
This work describes a variational technique to solve non-Hermitian quantum systems, in particular those with negative coupling quartic self-interaction. Differences of applying var…
Testing Scalar Field Self-Dualities in d=2 using a Variational Method
Paul Romatschke, Ulrike Romatschke
Recently, self-dualities based on saddle-point expansions have been proposed as a means to obtain qualitative non-perturbative information in scalar field theories. In this work, w…
Phase Diagram and Finite Temperature Properties of Negative Coupling Scalar Field Theory
Paul Romatschke
In this work, I consider scalar field theory with negative quartic self-interaction, corresponding to an upside-down classical potential. Despite not possessing a classically stabl…
On self-dualities for scalar theory
Paul Romatschke
Scalar field theory is studied by constructing interacting saddle point expansions in the symmetric and broken phase, respectively. Focusing on analytically tractable saddle expans…
On the negative coupling O(N) model in 2d at high temperature
Paul Romatschke
In this work, I consider N-component scalar quantum field theory in two dimensions interacting with an upside-down quartic potential. Working in the large N limit, the model can be…
Out-Of-Time-Ordered-Correlators for the Pure Inverted Quartic Oscillator: Classical Chaos meets Quantum Stability
Paul Romatschke
Out-of-time-ordered-correlators (OTOCs) have been suggested as a means to diagnose chaotic behavior in quantum mechanical systems. Recently, it was found that OTOCs display exponen…