287 citations · 2.9k across the 89 of their papers we have counts for
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Cosmological Particle Production: A Review
L. H. Ford
This article will review quantum particle creation in expanding universes. The emphasis will be on the basic physical principles and on selected applications to cosmological models…
Spacetime geometry fluctuations and geodesic deviation
H. S. Vieira, L. H. Ford, V. B. Bezerra
The quantum fluctuations of the geodesic deviation equation in a flat background spacetime are discussed. We calculate the resulting mean squared fluctuations in the relative veloc…
Quantum Stress Tensor Fluctuations and Primordial Gravity Waves
Jen-Tsung Hsiang, L. H. Ford, Kin-Wang Ng +1
We examine the effect of the stress tensor of a quantum matter field, such as the electromagnetic field, on the spectrum of primordial gravity waves expected in inflationary cosmol…
Decoherence induced by long wavelength gravitons
V. A. De Lorenci, L. H. Ford
We discuss how a background bath of gravitons can induce decoherence of quantum systems. The mechanism is dephasing, the loss of phase coherence due to quantum geometry fluctuation…
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…
An Analog Model for Light Propagation in Semiclassical Gravity
C. H. G. Bessa, V. A. De Lorenci, L. H. Ford
We treat a model based upon nonlinear optics for the semiclassical gravitational effects of quantum fields upon light propagation. Our model uses a nonlinear material with a nonzer…
Non-Cancellation of Quantum Geometry Fluctuations
Victor Parkinson, L. H. Ford
Quantum vacuum fluctuations tend to be strongly anti-correlated, which reduces their observable effects. However, time dependence can upset the cancellation of these anti-correlate…
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…
An Analog Model for Quantum Lightcone Fluctuations in Nonlinear Optics
L. H. Ford, V. A. De Lorenci, G. Menezes +1
We propose an analog model for quantum gravity effects using nonlinear dielectrics. Fluctuations of the spacetime lightcone are expected in quantum gravity, leading to variations i…
Quantum Stress Tensor Fluctuation Effects in Inflationary Cosmology
Jen-Tsung Hsiang, Chun-Hsien Wu, L. H. Ford +1
We review several related investigations of the effects of the quantum stress tensor of a conformal field in inflationary cosmology. Particular attention will be paid to the effect…
Gravity Waves from Quantum Stress Tensor Fluctuations in Inflation
Chun-Hsien Wu, Jen-Tsung Hsiang, L. H. Ford +1
We consider the effects of the quantum stress tensor fluctuations of a conformal field in generating gravity waves in inflationary models. We find a non-scale invariant, non-Gaussi…
Quantum Modifications to Gravity Waves in de Sitter Spacetime
Jen-Tsung Hsiang, L. H. Ford, Da-Shin Lee +1
We treat a model in which tensor perturbations of de~Sitter spacetime, represented as a spatially flat model, are modified by the effects of the vacuum fluctuations of a massless c…
Quantum Lightcone Fluctuations in Compactified Spacetimes
Hongwei Yu, N. F. Svaiter, L. H. Ford
We treat the effects of compactified spatial dimensions on the propagation of light in the uncompactified directions in the context of linearized quantum gravity. We find that the…
Brownian Motion in Robertson-Walker Space-Times from electromagnetic Vacuum Fluctuations
Carlos H. G. Bessa, Valdir B. Bezerra, L. H. Ford
We consider classical particles coupled to the quantized electromagnetic field in the background of a spatially flat Robertson-Walker universe. We find that these particles typical…
Enhanced Black Hole Horizon Fluctuations
R. T. Thompson, L. H. Ford
We discuss the possible role of quantum horizon fluctuations on black hole radiance, especially whether they can invalidate Hawking's analysis based upon transplanckian modes. We a…
Enhanced Geometry Fluctuations in Minkowski and Black Hole Spacetimes
R. T. Thompson, L. H. Ford
We will discuss selected physical effects of spacetime geometry fluctuations, especially the operational signatures of geometry fluctuations and their effects on black hole horizon…
Quantum Stress Tensor Fluctuations and their Physical Effects
L. H. Ford, Chun-Hsien Wu
We summarize several aspects of recent work on quantum stress tensor fluctuations and their role in driving fluctuations of the gravitational field. The role of correlations and an…
Possible Constraints on the Duration of Inflationary Expansion from Quantum Stress Tensor Fluctuations
Chun-Hsien Wu, Kin-Wang Ng, L. H. Ford
We discuss the effect of quantum stress tensor fluctuations in deSitter spacetime upon the expansion of a congruence of timelike geodesics. We treat a model in which the expansion…
Spectral Line Broadening and Angular Blurring due to Spacetime Geometry Fluctuations
R. T. Thompson, L. H. Ford
We treat two possible phenomenological effects of quantum fluctuations of spacetime geometry: spectral line broadening and angular blurring of the image of a distance source. A geo…
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…
Spacetime in Semiclassical Gravity
L. H. Ford
This article will summarize selected aspects of the semiclassical theory of gravity, which involves a classical gravitational field coupled to quantum matter fields. Among the issu…
Stochastic Spacetime and Brownian Motion of Test Particles
L. H. Ford
The operational meaning of spacetime fluctuations is discussed. Classical spacetime geometry can be viewed as encoding the relations between the motions of test particles in the ge…
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…
Effects of Quantum Stress Tensor Fluctuations with Compact Extra Dimensions
J. Borgman, L. H. Ford
The effects of compact extra dimensions upon quantum stress tensor fluctuations are discussed. It is argued that as the compactification volume decrease, these fluctuations increas…