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Probabilistic model checking for systems with large or unbounded state space is a challenging computational problem in formal modelling and its applications. Numerical algorithms require an explicit representation of the state space, while…

Logic in Computer Science · Computer Science 2018-06-12 Dimitrios Milios , Guido Sanguinetti , David Schnoerr

We study the internal dynamics of a hypothetical spaceship traveling on a close timelike curve in an axially symmetric universe. We choose the curve so that the generator of evolution in proper time is the angular momentum. Using Wigner's…

General Relativity and Quantum Cosmology · Physics 2024-12-13 Lorenzo Gavassino

Quantum retrodiction involves finding the probabilities for various preparation events given a measurement event. This theory has been studied for some time but mainly as an interesting concept associated with time asymmetry in quantum…

Quantum Physics · Physics 2009-11-07 David T. Pegg , Stephen M. Barnett , John Jeffers

Although the suspicion that quantum mechanics is emergent has been lingering for a long time, only now we begin to understand how a bridge between classical and quantum mechanics might be squared with Bell's inequalities and other…

Quantum Physics · Physics 2013-08-06 Gerard 't Hooft

Collapse models are modifications of quantum theory where the wave function is treated as physically real and the collapse of the wave function is a physical process. This appears to introduce a time reversal asymmetry into the dynamics of…

Quantum Physics · Physics 2015-02-25 Daniel Bedingham , Owen Maroney

It is notorious that quantum mechanics cannot predict well-defined values for all physical quantities. Less well-known, however, is the fact that quantum mechanics is unable to furnish -- without additional assumptions -- probabilistic…

Quantum Physics · Physics 2025-09-24 Matheus V. Scherer , Alexandre D. Ribeiro , Renato M. Angelo

In order to perceive that a physical system evolves in time, two requirements must be met: (a) it must be possible to define a "clock" and (b) it must be possible to make a copy of the state of the system, that can be reliably retrieved to…

Quantum Physics · Physics 2015-07-14 S. Nicolis

It has been suggested that the cosmic history might repeat in cycles, with an infinite series of similar aeons in the past and the future. Here, we instead propose that the cosmic history repeats itself exactly, constructing a universe on a…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-18 Elizabeth Gould , Niayesh Afshordi

Quantum retrodiction is a time-symmetric approach to quantum mechanics with applications in a number of important problems. One of the major challenges to its more widespread applicability is the restriction of its symmetric formalism to…

Quantum Physics · Physics 2020-06-30 Dov Fields , Abdelali Sajia , János A. Bergou

A legend tells that once Loschmidt asked Boltzmann on what happens to his statistical theory if one inverts the velocities of all particles, so that, due to the reversibility of Newton's equations, they return from the equilibrium to a…

Quantum Physics · Physics 2009-11-07 B. Georgeot , D. L. Shepelyansky

By analogy with the theory of Backward Stochastic Differential Equations, we define Backward Stochastic Difference Equations on spaces related to discrete time, finite state processes. This paper considers these processes as constructions…

Probability · Mathematics 2010-07-12 Samuel N. Cohen , Robert J. Elliott

The basic concept of the two-state vector formalism, which is the time symmetric approach to quantum mechanics, is the backward evolving quantum state. However, due to the time asymmetry of the memory's arrow of time, the possible ways to…

Quantum Physics · Physics 2015-06-26 Lev Vaidman

We analyze the estimation of a time dependent perturbation acting on a continuously monitored quantum system. We describe the temporal fluctuations of the perturbation by a Hidden Markov Model, and we combine quantum measurement theory and…

Quantum Physics · Physics 2021-06-08 Claus Normann Madsen , Lia Valdetaro , Klaus Mølmer

A model quantum cosmology is used to illustrate how arrows of time emerge in a universe governed by a time-neutral dynamical theory constrained by time asymmetric initial and final boundary conditions represented by initial and final…

General Relativity and Quantum Cosmology · Physics 2020-02-18 James B. Hartle

This relativistic, time-travel spacetime is everywhere metrically flat, excepting a conical singularity. Observers following timelike geodesics can eventually encounter their past selves, aging in the opposite time sense. The spacetime is…

General Relativity and Quantum Cosmology · Physics 2024-12-24 John D. Norton

Computing the distribution of trajectories from a Gaussian Process model of a dynamical system is an important challenge in utilizing such models. Motivated by the computational cost of sampling-based approaches, we consider approximations…

Machine Learning · Statistics 2023-05-16 Steffen Ridderbusch , Sina Ober-Blöbaum , Paul Goulart

Frauchiger and Renner recently cast doubt on the universal applicability of Quantum Mechanics [1]. In the following, it is pointed out that their conclusion of one of three common-sense conditions, demanded for Quantum Mechanics, being…

General Physics · Physics 2020-04-23 Knud Thomsen

Recent analysis of classical algorithms resulted in their axiomatization as transition systems satisfying some simple postulates, and in the formulation of the Abstract State Machine Theorem, which assures us that any classical algorithm…

Logic in Computer Science · Computer Science 2024-10-15 Andreas Blass , Nachum Dershowitz , Yuri Gurevich

Within the context of quantum teleportation, a proposed intuitive model to explain bipartite entanglement describes the scheme as being the same qubit of information evolving along and against the flow of time of an external observer. We…

Quantum Physics · Physics 2009-11-11 M. Laforest , J. Baugh , R. Laflamme

Suppose that you're going to school and arrive at a bus stop. How long do you have to wait before the next bus arrives? Surprisingly, it is longer - possibly much longer - than what the bus schedule suggests intuitively. This phenomenon,…

History and Overview · Mathematics 2020-09-24 Naoki Masuda , Mason A. Porter