60 citations · 352 across the 21 of their papers we have counts for
23 papers
How I Learned to Stop Worrying and Love the Redfield Equation: Completely-Positive Resummation of Non-Markovian Dynamics
Greg Kaplanek, Jason Pollack
The Redfield equation with time-dependent coefficients (or TCL2 equation) gives one of the simplest perturbative descriptions of open quantum system dynamics derived from a microsc…
Tensor Catalyzed Decoherence of Primordial Scalar Fluctuations
C. P. Burgess, D. Dineen, R. Holman +1
We provide the first complete calculation of the leading contribution to the decoherence of primordial fluctuations in the scalar part of the metric fluctuations within simplest, s…
Quantum Stochastic Inflation
Robson Christie, Jaewoo Joo, Greg Kaplanek +2
We formulate stochastic inflation in an open quantum system framework. The field coarse-grained in a patch of fixed physical size, and the total momentum of that patch, form a cano…
Schwinger-Keldysh Path Integral for Gauge theories
Greg Kaplanek, Maria Mylova, Andrew J. Tolley
We develop the Schwinger-Keldysh path-integral formalism for open non-Abelian gauge theories that are gauge-fixed via the BRST method in covariant gauges. We focus on generic initi…
Mixed signals in the IR: Positivity bounds with indefinite species
Claudia de Rham, Sumer Jaitly, Greg Kaplanek
In theories with multiple particle species standard fixed-t positivity bounds do not directly apply to 2-to-2 definite species scattering amplitudes when the initial and final stat…
Gauging Open EFTs from the top down
Greg Kaplanek, Maria Mylova, Andrew J. Tolley
We present explicit top-down calculations of Open EFTs for gauged degrees of freedom with a focus on the effects of gauge fixing. Starting from the in-in contour with two copies of…
Cosmic Lockdown: When Decoherence Saves the Universe from Tunneling
Robson Christie, Jaewoo Joo, Greg Kaplanek +2
We investigate how quantum decoherence influences the tunneling dynamics of quantum fields in cosmological spacetimes. Specifically, we study a scalar field in an asymmetric double…
Inflationary Decoherence from the Gravitational Floor
C. P. Burgess, R. Holman, Greg Kaplanek
We re-examine the decoherence rate of primordial fluctuations within minimal inflationary models, using only the gravitational interactions required for the underlying fluctuation-…
Lindblad evolution as gradient flow
Greg Kaplanek, Alexander Maloney, Jason Pollack +1
We give a simple argument that, for a large class of jump operators, the Lindblad evolution can be written as a gradient flow in the space of density operators acting on a Hilbert…
Does decoherence violate decoupling?
C. P. Burgess, Thomas Colas, R. Holman +1
Recent calculations in both flat and de Sitter spacetimes have highlighted a tension between the decoupling of high-energy physics from low-energy degrees of freedom and the expect…
In-in formalism for the entropy of quantum fields in curved spacetimes
Thomas Colas, Julien Grain, Greg Kaplanek +1
We show how to compute the purity and entanglement entropy for quantum fields in a systematic perturbative expansion. To that end, we generalize the in-in formalism to non-unitary…
Cosmic Purity Lost: Perturbative and Resummed Late-Time Inflationary Decoherence
C. P. Burgess, Thomas Colas, R. Holman +2
We compute the rate with which unobserved fields decohere other fields to which they couple, both in flat space and in de Sitter space, for spectator scalar fields prepared in thei…
Decoherence out of fire: Purity loss in expanding and contracting universes
Thomas Colas, Claudia de Rham, Greg Kaplanek
We investigate quantum decoherence in a class of models which interpolates between expanding (inflation) and contracting (ekpyrosis) scenarios. For the cases which result in a scal…
Gravity, Horizons and Open EFTs
C. P. Burgess, Greg Kaplanek
Wilsonian effective theories exploit hierarchies of scale to simplify the description of low-energy behaviour and play as central a role for gravity as for the rest of physics. The…
Minimal decoherence from inflation
C. P. Burgess, R. Holman, Greg Kaplanek +2
We compute the rate with which super-Hubble cosmological fluctuations are decohered during inflation, by their gravitational interactions with unobserved shorter-wavelength scalar…
Effective master equations for two accelerated qubits
Greg Kaplanek, Erickson Tjoa
We revisit the problem involving two constantly accelerating Unruh-DeWitt detectors using Open Effective Field Theory methods. We study the time evolution of the joint detector sta…
Quantum Hotspots: Mean Fields, Open EFTs, Nonlocality and Decoherence Near Black Holes
C. P. Burgess, R. Holman, G. Kaplanek
Effective theories describing black hole exteriors resemble open quantum systems inasmuch as many unmeasurable degrees of freedom beyond the horizon interact with those we can see.…
Qubit Heating Near a Hotspot
G. Kaplanek, C. P. Burgess, R. Holman
Effective theories describing black hole exteriors contain many open-system features due to the large number of gapless degrees of freedom that lie beyond reach across the horizon.…
Influence Through Mixing: Hotspots as Benchmarks for Basic Black-Hole Behaviour
G. Kaplanek, C. P. Burgess, R. Holman
Effective theories are being developed for fields outside black holes, often with an unusual open-system feel due to the influence of large number of degrees of freedom that lie ou…
Qubits on the Horizon: Decoherence and Thermalization near Black Holes
Greg Kaplanek, C. P. Burgess
We examine the late-time evolution of a qubit (or Unruh-De Witt detector) that hovers very near to the event horizon of a Schwarzschild black hole, while interacting with a free qu…
Hot Cosmic Qubits: Late-Time de Sitter Evolution and Critical Slowing Down
Greg Kaplanek, C. P. Burgess
Temporal evolution of a comoving qubit coupled to a scalar field in de Sitter space is studied with an emphasis on reliable extraction of late-time behaviour. The phenomenon of cri…
Hot Accelerated Qubits: Decoherence, Thermalization, Secular Growth and Reliable Late-time Predictions
Greg Kaplanek, C. P. Burgess
We compute how an accelerating qubit coupled to a scalar field - i.e. an Unruh-DeWitt detector - evolves in flat space, with an emphasis on its late-time behaviour. When calculable…
Failure of Perturbation Theory Near Horizons: the Rindler Example
C. P. Burgess, Joshua Hainge, Greg Kaplanek +1
Persistent puzzles to do with information loss for black holes have stimulated critical reassessment of the domain of validity of semiclassical EFT reasoning in curved spacetimes,…