175 citations · 1.6k across the 58 of their papers we have counts for
33 papers · 1 filter
Poincaré symmetries and representations in pseudo-Hermitian quantum field theory
Esra Sablevice, Peter Millington
This paper explores quantum field theories with pseudo-Hermitian Hamiltonians, where PT-symmetric Hamiltonians serve as a special case. In specific regimes, these pseudo-Hermitian…
Vertex functions and their flow equations from the 2PI effective action
Peter Millington, Paul M. Saffin
By exploiting the convexity of the two-particle-irreducible (2PI) effective action, we describe a procedure for extracting n-point vertex functions. This procedure is developed wit…
Discrete spacetime symmetries, second quantization, and inner products in a non-Hermitian Dirac fermionic field theory
Jean Alexandre, John Ellis, Peter Millington
We extend to a non-Hermitian fermionic quantum field theory with PT symmetry our previous discussion of second quantization, discrete symmetry transformations, and inner products i…
Fifth forces and broken scale symmetries in the Jordan frame
Edmund J. Copeland, Peter Millington, Sergio Sevillano Muñoz
We study the origin of fifth forces in scalar-tensor theories of gravity in the so-called Jordan frame, where the modifications to the gravitational sector are manifest. We focus o…
IR/UV mixing from local similarity maps of scalar non-Hermitian field theories
Maxim N. Chernodub, Peter Millington
We propose to "gauge" the group of similarity transformations that acts on a space of non-Hermitian scalar theories. We introduce the "similarity gauge field", which acts as a gaug…
Benchmarking regulator-sourced 2PI and average 1PI flow equations in zero dimensions
Peter Millington, Paul M. Saffin
We elucidate the regulator-sourced 2PI and average 1PI approaches for deriving exact flow equations in the case of a zero dimensional quantum field theory, wherein the scale depend…
Statistics on Lefschetz thimbles: Bell/Leggett-Garg inequalities and the classical-statistical approximation
Peter Millington, Zong-Gang Mou, Paul M. Saffin +1
Inspired by Lefschetz thimble theory, we treat Quantum Field Theory as a statistical theory with a complex Probability Distribution Function (PDF). Such complex-valued PDFs permit…
Discrete spacetime symmetries and particle mixing in non-Hermitian scalar quantum field theories
Jean Alexandre, John Ellis, Peter Millington
We discuss second quantization, discrete symmetry transformations and inner products in free non-Hermitian scalar quantum field theories with PT symmetry, focusing on a prototype m…
PT-Symmetric Non-Hermitian Quantum Field Theories with Supersymmetry
Jean Alexandre, John Ellis, Peter Millington
We formulate supersymmetric non-Hermitian quantum field theories with PT symmetry, starting with free chiral boson/fermion models and then including trilinear superpotential intera…
Spontaneously Breaking Non-Abelian Gauge Symmetry in Non-Hermitian Field Theories
Jean Alexandre, John Ellis, Peter Millington +1
We generalise our previous formulation of gauge-invariant PT-symmetric field theories to include models with non-Abelian symmetries and discuss the extension to such models of the…
A new functional RG flow: regulator-sourced 2PI versus average 1PI
Elizabeth Alexander, Peter Millington, Jordan Nursey +1
We derive the renormalization group evolution of the quartic scalar theory with spontaneous symmetry breaking from an alternative flow equation, obtained within the externally sour…
Alternative flow equation for the functional renormalization group
Elizabeth Alexander, Peter Millington, Jordan Nursey +1
We derive an alternative to the Wetterich-Morris-Ellwanger equation by means of the two-particle irreducible (2PI) effective action, exploiting the method of external sources due t…
Visualising quantum effective action calculations in zero dimensions
Peter Millington, Paul M. Saffin
We present an explicit treatment of the two-particle-irreducible (2PI) effective action for a zero-dimensional quantum field theory. The advantage of this simple playground is that…
Open quantum dynamics induced by light scalar fields
Clare Burrage, Christian Käding, Peter Millington +1
We consider the impact of a weakly coupled environment comprising a light scalar field on the open dynamics of a quantum probe field, resulting in a master equation for the probe f…
Particle level screening of scalar forces in 1+1 dimensions
Clare Burrage, Benjamin Elder, Peter Millington
We investigate how non-linear scalar field theories respond to point sources. Taking the symmetron as a specific example of such a theory, we solve the non-linear equation of motio…
Gauge invariance and the Englert-Brout-Higgs mechanism in non-Hermitian field theories
Jean Alexandre, John Ellis, Peter Millington +1
We discuss -symmetric Abelian gauge field theories, as well as their extension to the Englert-Brout-Higgs mechanism for generating a mass for a vector boson. Gauge in…
Boltzmann equations for preheating
William T. Emond, Peter Millington, Paul M. Saffin
We derive quantum Boltzmann equations for preheating by means of the density matrix formalism, which account for both the non-adiabatic particle production and the leading collisio…
Radiative effects on false vacuum decay in Higgs-Yukawa theory
Wen-Yuan Ai, Bjorn Garbrecht, Peter Millington
We derive fermionic Green's functions in the background of the Euclidean solitons describing false vacuum decay in a prototypal Higgs-Yukawa theory. In combination with appropriate…
Spontaneous symmetry breaking and the Goldstone theorem in non-Hermitian field theories
Jean Alexandre, John Ellis, Peter Millington +1
We demonstrate the extension to PT-symmetric field theories of the Goldstone theorem, confirming that the spontaneous appearance of a field vacuum expectation value via minimisatio…
Fifth forces, Higgs portals and broken scale invariance
Clare Burrage, Edmund J. Copeland, Peter Millington +1
We study the relationship between the strength of fifth forces and the origin of scale breaking in the Standard Model (SM) of particle physics. We start with a light scalar field t…
Fluctuations about the Fubini-Lipatov instanton for false vacuum decay in classically scale invariant models
Bjorn Garbrecht, Peter Millington
For a scalar theory whose classical scale invariance is broken by quantum effects, we compute self-consistent bounce solutions and Green's functions. Deriving analytic expressions,…
Energy-parity from a bicomplex algebra
Max Edward Laycock, Peter Millington
By replacing the field of complex numbers with the commutative ring of bicomplex numbers, we attempt to construct interacting scalar quantum field theories that feature both positi…
Consistent description of field theories with non-Hermitian mass terms
Jean Alexandre, Peter Millington, Dries Seynaeve
We review how to describe a field theory that includes a non-Hermitian mass term in the region of parameter space where the Lagrangian is -symmetric. The discrete symmetries of…
Non-perturbative aspects of galileon duality
Peter Millington, Florian Niedermann, Antonio Padilla
We study quantum aspects of the galileon duality, especially in the case of a particular interacting galileon theory that is said to be dual to a free theory through the action of…