934 citations · 3.5k across the 98 of their papers we have counts for
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What is the No-Boundary Wave Function of the Universe?
Jonathan J. Halliwell, James B. Hartle, Thomas Hertog
We specify the semiclassical no-boundary wave function of the universe without relying on a functional integral of any kind. The wave function is given as a sum of specific saddle…
Observational Implications of Fuzzball Formation
Thomas Hertog, James Hartle
We consider the quantum dynamics of gravitational collapse in a model in which the wave function spreads out over a large ensemble of geometries as envisioned in the fuzzball propo…
One Bubble to Rule Them All
James Hartle, Thomas Hertog
We apply the principles of quantum mechanics and quantum cosmology to predict probabilities for our local observations of a universe undergoing false vacuum eternal inflation. At a…
Quantum Transitions Between Classical Histories: Bouncing Cosmologies
James Hartle, Thomas Hertog
In a quantum theory of gravity spacetime behaves classically when quantum probabilities are high for histories of geometry and field that are correlated in time by the Einstein equ…
Quantum Probabilities for Inflation from Holography
James B. Hartle, S. W. Hawking, Thomas Hertog
The evolution of the universe is determined by its quantum state. The wave function of the universe obeys the constraints of general relativity and in particular the Wheeler-DeWitt…
Accelerated Expansion from Negative Λ
James B. Hartle, S. W. Hawking, Thomas Hertog
Wave functions specifying a quantum state of the universe must satisfy the constraints of general relativity, in particular the Wheeler-DeWitt equation (WDWE). We show for a wide c…
Holographic No-Boundary Measure
Thomas Hertog, James Hartle
We show that the complex saddle points of the no-boundary wave function with a positive cosmological constant and a positive scalar potential have a representation in which the geo…
Arrows of Time in the Bouncing Universes of the No-boundary Quantum State
James Hartle, Thomas Hertog
We derive the arrows of time of our universe that follow from the no-boundary theory of its quantum state (NBWF) in a minisuperspace model. Arrows of time are viewed four-dimension…
Local Observation in Eternal inflation
James Hartle, S. W. Hawking, Thomas Hertog
We consider landscape models that admit several regions where the conditions for eternal inflation hold. It is shown that one can use the no-boundary wave function to calculate sma…
The Xerographic Distribution: Scientific Reasoning in a Large Universe
Mark Srednicki, James Hartle
As observers of the universe we are physical systems within it. If the universe is very large in space and/or time, the probability becomes significant that the data on which we ba…
The No-Boundary Measure in the Regime of Eternal Inflation
James Hartle, S. W. Hawking, Thomas Hertog
The no-boundary wave function (NBWF) specifies a measure for prediction in cosmology that selects inflationary histories and remains well behaved for spatially large or infinite un…
Science in a Very Large Universe
Mark Srednicki, James Hartle
As observers of the universe we are quantum physical systems within it. If the universe is very large in space and/or time, the probability becomes significant that the data on whi…
Replication Regulates Volume Weighting in Quantum Cosmology
James Hartle, Thomas Hertog
Probabilities for observations in cosmology are conditioned both on the universe's quantum state and on local data specifying the observational situation. We show the quantum state…
The Classical Universes of the No-Boundary Quantum State
James B. Hartle, S. W. Hawking, Thomas Hertog
We analyze the origin of the quasiclassical realm from the no-boundary proposal for the universe's quantum state in a class of minisuperspace models. The models assume homogeneous,…
The No-Boundary Measure of the Universe
James B. Hartle, S. W. Hawking, Thomas Hertog
We consider the no-boundary proposal for homogeneous isotropic closed universes with a cosmological constant and a scalar field with a quadratic potential. In the semi-classical li…
Are We Typical?
James B. Hartle, Mark Srednicki
Bayesian probability theory is used to analyze the oft-made assumption that humans are typical observers in the universe. Some theoretical calculations make the {\it selection fall…
Observables in effective gravity
Steven B. Giddings, Donald Marolf, James B. Hartle
We address the construction and interpretation of diffeomorphism-invariant observables in a low-energy effective theory of quantum gravity. The observables we consider are construc…