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Related papers: The Algebra of the Pseudo-Observables III: Transfo…

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Starting from a generalized Hamilton-Jacobi formalism, we develop a new framework for constructing observables and their evolution in theories invariant under global time reparametrizations. Our proposal relaxes the usual Dirac prescription…

General Relativity and Quantum Cosmology · Physics 2017-11-15 Sean Gryb , Karim Thebault

The discussion is limited to first-class parametrized systems, where the definition of time evolution and observables is not trivial, and to finite dimensional systems in order that technicalities do not obscure the conceptual framework.…

General Relativity and Quantum Cosmology · Physics 2009-10-28 Petr Hajicek

In this second paper, we develop the full mathematical structure of the algebra of the pseudo-observables, in order to solve the quantum measurement problem. Quantum state vectors are recovered but as auxiliary pseudo-observables storing…

Quantum Physics · Physics 2025-08-21 Edoardo Piparo

A commonly adopted relational account of time evolution in generally-covariant systems, and more specifically in quantum cosmology, is argued to be unsatisfactory, insofar as it describes evolution relative to observed readings of a clock…

General Relativity and Quantum Cosmology · Physics 2011-03-10 Ian D. Lawrie

One solution to the so-called problem of time is to construct certain Dirac observables, sometimes called evolving constants of motion. There has been some discussion in the literature about the interpretation of such observables, and in…

General Relativity and Quantum Cosmology · Physics 2009-11-19 Donald Marolf

In this paper, it is shown why Lorentz Transformation implies the general case where observed events are not necessarily in the inertia frame of any observer but assumes a special scenario when determining the length contraction and time…

General Physics · Physics 2012-09-24 Ibrahim M. Alabdulmohsin

The classical and quantum dynamics of simple time-reparametrization- invariant models containing two degrees of freedom are studied in detail. Elimination of one ``clock'' variable through the Hamiltonian constraint leads to a description…

General Relativity and Quantum Cosmology · Physics 2009-10-28 Ian D. Lawrie , Richard J. Epp

We propose to use the effect of measurements instead of their number to study the time evolution of quantum systems under monitoring. This time redefinition acts like a microscope which blows up the inner details of seemingly instantaneous…

Quantum Physics · Physics 2016-02-02 Michel Bauer , Denis Bernard , Antoine Tilloy

We present an outline of a technique to associate certain methods from time optimal quantum control with various transforms on SU(3). Unitary operators are taken from certain time dependent Hamiltonians and transformation laws are derived.…

Quantum Physics · Physics 2019-07-31 P. G. Morrison

(abridged)The achievements of the present work include: a) A clarification of the multiple definition given by Bergmann of the concept of {\it (Bergmann) observable. This clarification leads to the proposal of a {\it main conjecture}…

General Relativity and Quantum Cosmology · Physics 2015-06-25 Luca Lusanna , Massimo Pauri

The algebra of observables associated with a quantum field theory is invariant under the connected component of the Lorentz group and under parity reversal, but it is not invariant under time reversal. If we take general covariance…

Quantum Physics · Physics 2008-10-28 Peter Morgan

In this paper, we will first clarify the physical meaning of having a minimum measurable time. Then we will combine the deformation of the Dirac equation due to the existence of minimum measurable length and time scales with its deformation…

General Physics · Physics 2016-02-04 Mir Faizal , Sergey I. Kruglov

The time evolution of the universe is usually mathematically described under a continuous time and thus time reversible. Here, the consequences of studying the evolution of a homogenous isotropic universe by time continuous reversible…

General Physics · Physics 2019-10-23 Roland Riek

Assuming the existence of a preferred aether frame and the anisotropy of the one-way speed of light in platforms different from the aether frame, we derive the space and time transformations relative to bodies moving in any direction of…

General Physics · Physics 2010-11-19 Joseph Levy

The long-standing problem of time in canonical quantum gravity is the source of several conceptual and technical issues. Here, recent mathematical results are used to provide a consistent algebraic formulation of dynamical symplectic…

General Relativity and Quantum Cosmology · Physics 2023-01-04 Martin Bojowald , Artur Tsobanjan

This paper considers a new and deeply challenging face of the problem of time in the context of cosmology drawing on the work of Thiemann (2006, 2007). Thiemann argues for a radical response to the cosmic problem of time that requires us to…

General Relativity and Quantum Cosmology · Physics 2025-05-09 Nicola Bamonti , Karim P. Y. Thébault

"The last remnant of physical objectivity of space-time" is disclosed, beyond the Leibniz equivalence, in the case of a continuous family of spatially non-compact models of general relativity. The {\it physical individuation} of…

General Relativity and Quantum Cosmology · Physics 2007-05-23 L. Lusanna , M. Pauri

"It is utterly beyond our power to measure the changes of things by time. Quite the contrary, time is an abstraction at which we arrive through the changes of things." Ernst Mach [1]. What change? Three answers to this are `any change'…

General Relativity and Quantum Cosmology · Physics 2013-04-22 Edward Anderson

Evolution of systems in which Hamiltonians are generators of gauge transformations is a notion that requires more structure than the canonical theory provides. We identify and study this additional structure in the framework of relational…

General Relativity and Quantum Cosmology · Physics 2013-10-30 Andrea Dapor , Wojciech Kamiński , Jerzy Lewandowski , Jedrzej Świeżewski

A cosmological time variable is emerged from the Hamiltonian formulation of Friedmann model to measure the evolution of dynamical observables in the theory. A set of observables has been identified for the theory on the null hypersurfaces…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Hossein Farajollahi
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