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Related papers: Quantum Evoluton and Space-time Structure

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A slight modification of one axiom of quantum theory changes a reversible theory into a time asymmetric theory. Whereas the standard Hilbert space axiom does not distinguish mathematically between the space of states (in-states of…

Quantum Physics · Physics 2014-11-18 A. Bohm , Mark Loewe , Bryan Van de Ven

Quantum mechanics is formulated on a Hilbert space that is assumed to be separable. However, there seems to be no clear reason justifying this assumption. Does it have physical implications? We answer in the positive by proposing a test…

Quantum Physics · Physics 2024-12-04 Miguel Gallego

It is expected that a quantum theory of gravity will radically alter our current notion of spacetime geometry. However, contrary to what was commonly assumed for many decades, quantum gravity effects could manifest in scales much larger…

General Relativity and Quantum Cosmology · Physics 2026-05-14 Eduardo A. B. Oliveira , Andre G. S. Landulfo

It is shown that, with some reasonable assumptions, the theory of general relativity can be made compatible with quantum mechanics by using the field equations of general relativity to construct a Robertson-Walker metric for a quantum…

High Energy Physics - Theory · Physics 2007-05-23 Vu B Ho

It is argued that while quantum mechanics contains nonlocal or entangled states, the instantaneous or nonlocal influences sometimes thought to be present due to violations of Bell inequalities in fact arise from mistaken attempts to apply…

Quantum Physics · Physics 2012-02-22 Robert B. Griffiths

In quantum logic, i.e., within the structure of the Hilbert lattice imposed on all closed linear subspaces of a Hilbert space, the assignment of truth values to quantum propositions (i.e., experimentally verifiable propositions relating to…

Quantum Physics · Physics 2019-01-25 Arkady Bolotin

Quantum gravitational effects may induce stochastic fluctuations in the structure of space-time, to produce a characteristic foamy structure. It has been known for some time now that these fluctuations may have observable consequences for…

General Relativity and Quantum Cosmology · Physics 2016-11-09 R. Aloisio , P. Blasi , A. Galante , A. F. Grillo

Understanding the emergence of a tangible 4-dimensional space-time from a quantum theory of gravity promises to be a tremendously difficult task. This article makes the case that this task may not have to be carried. Space-time as we know…

History and Philosophy of Physics · Physics 2018-11-14 Antoine Tilloy

Recent developments in gravitational path integrals indicate that the nonperturbative physical Hilbert space of a closed universe is one-dimensional within each superselection sector. This raises a basic puzzle: how can a unique…

High Energy Physics - Theory · Physics 2026-03-03 Yasunori Nomura , Tomonori Ugajin

In fundamental theories that accounts for quantum gravitational effects, the spacetime causal structure is expected to be quantum uncertain. Previous studies of quantum causal structure focused on finite-dimensional systems. Here we present…

Quantum Physics · Physics 2019-02-18 Ding Jia

We conjecture that the relative rate of time evolution depends on the amount of quantum correlations in a system. This is motivated by the experimental work [1] which showed that quantum tunneling is not instantaneous. The non-zero…

Quantum Physics · Physics 2019-03-06 Vahid H. Ranjbar

The space time that is used in relativistic Quantum Mechanics and Quantum Field Theory is the Minkowski space time. Yet, as pointed out by several scholars this classical space time is incompatible with the Heisenberg Uncertainity…

General Physics · Physics 2007-05-23 B. G. Sidharth

It is seen that issues of unitarity raised by the evolution of the wave function in curved spacetime can be resolved by describing the evolution of quantum states in Minkowski tangent space. The treatment adheres closely to the orthodox…

General Relativity and Quantum Cosmology · Physics 2016-03-15 Charles Francis

The use of a relational time in quantum mechanics is a framework in which one promotes to quantum operators all variables in a system, and later chooses one of the variables to operate like a ``clock''. Conditional probabilities are…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Rodolfo Gambini , Rafael Porto , Jorge Pullin

In quantum physics, disturbance due to a measurement is not negligible. This requires the time parameter $t$ in the Schr\"odinger or Heisenberg equation to be considered differently from a time continuum of experimenter's clock $T$ on which…

Quantum Physics · Physics 2010-11-24 Yoshihiro Sato , Arno R. Bohm

A system of quantum reasoning for a closed system is developed by treating non-relativistic quantum mechanics as a stochastic theory. The sample space corresponds to a decomposition, as a sum of orthogonal projectors, of the identity…

Quantum Physics · Physics 2009-10-30 Robert B. Griffiths

A new dynamical paradigm merging quantum dynamics with cosmology is discussed. Time evolution involves a genuine passage of time, which distinguishes the formalism from those where dynamics in space is equivalent to statics in space-time.…

General Physics · Physics 2024-02-01 Marek Czachor

In the framework of quasi-Hermitian quantum mechanics it is shown that a weakening of the isotropy of the Hilbert-space geometry can help us to enlarge the domain of the parameters at which the evolution is unitary. The idea is tested using…

Quantum Physics · Physics 2024-08-15 Miloslav Znojil

The causal set approach to quantum gravity is based on the hypothesis that the underlying structure of spacetime is that of a random partial order. We survey some of the interesting mathematics that has arisen in connection with the causal…

Combinatorics · Mathematics 2015-10-20 Graham Brightwell , Malwina Luczak

In this paper we study the Hilbert space structure underlying the Koopman-von Neumann (KvN) operatorial formulation of classical mechanics. KvN limited themselves to study the Hilbert space of zero-forms that are the square integrable…

Quantum Physics · Physics 2009-11-07 E. Deotto , E. Gozzi , D. Mauro