109 citations · 1.3k across the 42 of their papers we have counts for
11 papers · 1 filter
Testing Whether Gravity Acts as a Quantum Entity When Measured
Farhan Hanif, Debarshi Das, Jonathan Halliwell +4
A defining signature of classical systems is "in principle measurability" without disturbance: a feature manifestly violated by quantum systems. We describe a multi-interferometer…
The no-boundary proposal in biaxial Bianchi IX minisuperspace
Oliver Janssen, Jonathan J. Halliwell, Thomas Hertog
We implement the no-boundary proposal for the wave function of the universe in an exactly solvable Bianchi IX minisuperspace model with two scale factors. We extend our earlier wor…
Damped perturbations in the no-boundary state
Juan Diaz Dorronsoro, Jonathan J. Halliwell, James B. Hartle +3
We evaluate the no-boundary path integral exactly in a Bianchi IX minisuperspace with two scale factors. In this model the no-boundary proposal can be implemented by requiring one…
The Real No-Boundary Wave Function in Lorentzian Quantum Cosmology
Juan Diaz Dorronsoro, Jonathan J. Halliwell, James B. Hartle +2
It is shown that the standard no-boundary wave function has a natural expression in terms of a Lorentzian path integral with its contour defined by Picard-Lefschetz theory. The wav…
The Interpretation of Quantum Cosmology and the Problem of Time
J. J. Halliwell
The development of quantum cosmology, in which Stephen Hawking played a crucial role, has frequently encountered substantial conceptual and technical difficulties related to the pr…
Life in an Energy Eigenstate: Decoherent Histories Analysis of a Model Timeless Universe
J. J. Halliwell, J. Thorwart
Inspired by quantum cosmology, in which the wave function of the universe is annihilated by the total Hamiltonian, we consider the internal dynamics of a simple particle system in…
Decoherent histories analysis of the relativistic particle
J. J. Halliwell, J. Thorwart
The Klein-Gordon equation is a useful test arena for quantum cosmological models described by the Wheeler-DeWitt equation. We use the decoherent histories approach to quantum theor…
Trajectories for the Wave Function of the Universe from a Simple Detector Model
J. J. Halliwell
Inspired by Mott's (1929) analysis of particle tracks in a cloud chamber, we consider a simple model for quantum cosmology which includes, in the total Hamiltonian, model detectors…
Generalized Uncertainty Relations and Long Time Limits for Quantum Brownian Motion Models
C. Anastopoulos, J. J. Halliwell
We study the time evolution of the reduced Wigner function for a class of quantum Brownian motion models. We derive two generalized uncertainty relations. The first consists of a s…
Aspects of the Decoherent Histories Approach to Quantum Mechanics
J. J. Halliwell
I give an informal overview of the decoherent histories approach to quantum mechanics, due to Griffiths, to Omnès, and to Gell-Mann and Hartle is given. Results on the connections…
The Interpretation of Quantum Cosmological Models
Jonathan J. Halliwell
We consider the problem of extracting physical predictions from the wave function of the universe in quantum cosmological models. We state the features of quantum cosmology an inte…