287 citations · 1.8k across the 25 of their papers we have counts for
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Probability distributions for quantum stress tensors in two and four dimensions
Christopher J. Fewster, L. H. Ford, Thomas A. Roman
The probability distributions for the smeared energy densities of quantum fields, in the two and four-dimensional Minkowski vacuum are discussed. These distributions share the prop…
Negative Energy Seen By Accelerated Observers
L. H. Ford, Thomas A. Roman
The sampled negative energy density seen by inertial observers, in arbitrary quantum states is limited by quantum inequalities, which take the form of an inverse relation between t…
Problems with wormholes which involve arbitrarily small amounts of exotic matter
C. J. Fewster, T. A. Roman
A quantum inequality bound on the expectation value of the null-contracted stress tensor in an arbitrary Hadamard state is used to obtain constraints on the geometries of traversab…
On wormholes with arbitrarily small quantities of exotic matter
C. J. Fewster, T. A. Roman
Recently several models of traversable wormholes have been proposed which require only arbitrarily small amounts of negative energy to hold them open against self-collapse. If the…
Minkowski Vacuum Stress Tensor Fluctuations
L. H. Ford, Thomas A. Roman
We study the fluctuations of the stress tensor for a massless scalar field in two and four-dimensional Minkowski spacetime in the vacuum state. Covariant expressions for the stress…
Energy Flux Correlations and Moving Mirrors
L. H. Ford, Thomas A. Roman
We study the quantum stress tensor correlation function for a massless scalar field in a flat two-dimensional spacetime containing a moving mirror. We construct the correlation fun…
Some Thoughts on Energy Conditions and Wormholes
Thomas A. Roman
This essay reviews some of the recent progress in the area of energy conditions and wormholes. Most of the discussion centers on the subject of ``quantum inequality'' restrictions…
Null energy conditions in quantum field theory
C. J. Fewster, T. A. Roman
For the quantised, massless, minimally coupled real scalar field in four-dimensional Minkowski space, we show (by an explicit construction) that weighted averages of the null-contr…
Spatially Averaged Quantum Inequalities Do Not Exist in Four-Dimensional Spacetime
L. H. Ford, Adam D. Helfer, Thomas A. Roman
We construct a particular class of quantum states for a massless, minimally coupled free scalar field which are of the form of a superposition of the vacuum and multi-mode two-part…
Constraints on Spatial distributions of Negative Energy
Arvind Borde, L. H. Ford, Thomas A. Roman
This paper initiates a program which seeks to study the allowed spatial distributions of negative energy density in quantum field theory. Here we deal with free fields in Minkowski…
Classical Scalar Fields and the Generalized Second Law
L. H. Ford, Thomas A. Roman
It has been shown that classical non-minimally coupled scalar fields can violate all of the standard energy conditions in general relativity. Violations of the null and averaged nu…
The Quantum Interest Conjecture
L. H. Ford, Thomas A. Roman
Although quantum field theory allows local negative energy densities and fluxes, it also places severe restrictions upon the magnitude and extent of the negative energy. The restri…
Quantum Inequalities and Singular Energy Densities
L. H. Ford, Michael J. Pfenning, Thomas A. Roman
There has been much recent work on quantum inequalities to constrain negative energy. These are uncertainty principle-type restrictions on the magnitude and duration of negative en…
A Superluminal Subway: The Krasnikov Tube
Allen E. Everett, Thomas A. Roman
The ``warp drive'' metric recently presented by Alcubierre has the problem that an observer at the center of the warp bubble is causally separated from the outer edge of the bubble…
Restrictions on Negative Energy Density in Flat Spacetime
L. H. Ford, Thomas A. Roman
In a previous paper, a bound on the negative energy density seen by an arbitrary inertial observer was derived for the free massless, quantized scalar field in four-dimensional Min…
Quantum Field Theory Constrains Traversable Wormhole Geometries
L. H. Ford, Thomas A. Roman
Recently a bound on negative energy densities in four-dimensional Minkowski spacetime was derived for a minimally coupled, quantized, massless, scalar field in an arbitrary quantum…
Averaged Energy Conditions and Evaporating Black Holes
L. H. Ford, Thomas A. Roman
In this paper the averaged weak (AWEC) and averaged null (ANEC) energy conditions, together with uncertainty principle-type restrictions on negative energy (``quantum inequalities'…
Averaged Energy Conditions and Quantum Inequalities
L. H. Ford, Thomas A. Roman
Connections are uncovered between the averaged weak (AWEC) and averaged null (ANEC) energy conditions, and quantum inequality restrictions on negative energy for free massless scal…
Motion of Inertial Observers Through Negative Energy
L. H. Ford, Thomas A. Roman
Recent research has indicated that negative energy fluxes due to quantum coherence effects obey uncertainty principle-type inequalities of the form $|ΔE|\,{Δτ} \lprox 1\,$. Here $|…
Inflating Lorentzian Wormholes
Thomas A. Roman
It has been speculated that Lorentzian wormholes of the Morris- Thorne type might be allowed by the laws of physics at submicroscopic, e.g. Planck, scales and that a sufficiently a…