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Related papers: Time in Quantum Mechanics and Quantum Field Theory

200 papers

In the early 2000s, the study of time operators advanced as one of the methods to understand the problem of time as mathematical science. However, the starting point for the time operator is to understand time as a problem of observation…

Quantum Physics · Physics 2020-01-10 Tadashi Fujimoto

We construct concrete examples of time operators for both continuous and discrete-time homogeneous quantum walks, and we determine their deficiency indices and spectra. For a discrete-time quantum walk, the time operator can be self-adjoint…

Mathematical Physics · Physics 2020-06-23 Daiju Funakawa , Yasumichi Matsuzawa , Akito Suzuki , Itaru Sasaki , Noriaki Teranishi

Attempts to treat time on an equivalent footing with space in quantum mechanics have been apparently dominated by `timeless' approaches, such as the one of Page and Wootters, which allow meaningful discussion of a `time operator'. However,…

Quantum Physics · Physics 2025-09-29 Michael Ridley , Eliahu Cohen

The problem of time in the quantization of gravity arises from the fact that time in Schroedinger's equation is a parameter. This sets time apart from the spatial coordinates, represented by operators in quantum mechanics (QM). Thus "time"…

General Relativity and Quantum Cosmology · Physics 2016-05-06 M. Bauer

Within the framework of self-adjoint operator of time in non-relativistic quantum mechanics some properties of solutions of Schroedinger equation, related to Hilbert space formalism, are investigated for two types of time dependent…

Quantum Physics · Physics 2017-01-26 Slobodan Prvanovic , Dusan Arsenovic

We consider the classical concept of time of permanence and observe that its quantum equivalent is described by a bona fide self-adjoint operator. Its interpretation, by means of the spectral theorem, reveals that we have to abandon not…

General Physics · Physics 2012-07-13 Massimiliano Sassoli de Bianchi

A self-adjoint operator with dimensions of time is explicitly constructed, and it is shown that its complete and orthonormal set of eigenstates can be used to define consistently a probability distribution of the time of arrival at a…

Quantum Physics · Physics 2008-02-03 V. Delgado , J. G. Muga

Time in relativity theory has a status different from that adopted by standard quantum mechanics, where time is considered as a parameter measured with reference to an external absolute Newtonian frame. This status strongly restricts its…

Quantum Physics · Physics 2023-10-26 M. Basil Altaie

There is no self adjoint time operator defined in quantum mechanics. However, time intervals can be defined in several ways and can also be probed experimentally. Our interest in this work is traversal time and signal propagation time.…

Quantum Physics · Physics 2018-06-19 P. Singha Deo , Urbashi Satpathi

Canonical quantization applied to closed systems leads to static equations, the Wheeler-deWitt equation in Quantum Gravity and the time independent Schr\"odinger equation in Quantum Mechanics. How to restore time is the Problem of Time(s).…

Quantum Physics · Physics 2022-01-21 M. Bauer , C. A. Aguillón

We introduce a self-adjoint time operator $T_w = i\hbar\bigl(\partial_E + \tfrac12\,\partial_E\ln w(E)\bigr)$ on the weighted energy space $L^2(\mathbb R,\,w(E)\,dE)$. Under mild conditions on the weight $w$ (positivity, local absolute…

Quantum Physics · Physics 2025-04-28 Radmir Kokoulin

Textbook quantum mechanics treats time as a classical parameter, and not as a quantum observable with an associated Hermitian operator. For this reason, to make sense of usual time-energy uncertainty relations such as $\Delta {t}\Delta…

Quantum Physics · Physics 2021-12-08 Matteo Fadel , Lorenzo Maccone

The operational formulations of quantum theory are drastically time oriented. However, to the best of our knowledge, microscopic physics is time-symmetric. We address this tension by showing that the asymmetry of the operational…

Quantum Physics · Physics 2021-08-11 Andrea Di Biagio , Pietro Donà , Carlo Rovelli

A quantum mechanical theory is proposed which abandons an external parameter ``time'' in favor of a self-adjoint operator on a Hilbert space whose elements represent measurement events rather than system states. The standard quantum…

Quantum Physics · Physics 2009-09-29 Kim Bostroem

As time is not an observable, we use Fisher information (FI) to address the problem of time. We show that the Hamiltonian constraint operator cannot be used to analyze any quantum process for quantum geometries that are associated with…

General Relativity and Quantum Cosmology · Physics 2022-09-27 Salman Sajad Wani , James Q. Quach , Mir Faizal

Time reversal symmetry occupies a distinctive role in quantum mechanics, fundamentally requiring an anti-unitary operator to ensure a physically consistent representation. As such, the time reversal operator combines a unitary…

General Relativity and Quantum Cosmology · Physics 2026-03-27 Ovidiu Racorean

We address the multiplicity of solutions to the time-energy canonical commutation relation for a given Hamiltonian. Specifically, we consider a particle spatially confined in a potential free interval, where it is known that two distinct…

Quantum Physics · Physics 2015-05-19 Roland Cristopher F. Caballar , Eric A. Galapon

A time operator is a Hermitian operator that is canonically conjugate to a given Hamiltonian. For a particle in 1-dimension, a Hamiltonian conjugate operator in position representation can be obtained by solving a hyperbolic second-order…

Quantum Physics · Physics 2024-09-06 Ralph Adrian E. Farrales , Herbert B. Domingo , Eric A. Galapon

We consider one-dimensional Pauli Hamiltonians in a bounded interval with possibly non-self-adjoint Robin-type boundary conditions. We study the influence of the spin-magnetic interaction on the interplay between the type of boundary…

Quantum Physics · Physics 2015-06-04 D. Kochan , D. Krejcirik , R. Novak , P. Siegl

I point out that if one defines the operator $U_R(t)$ as done by M. Znojil in his reply [arXiv:0711.0514v1] to my comment [arXiv:0711.0137v1] and also accepts the validity of the defining relation of $U_R(t)$ as given in his paper…

Quantum Physics · Physics 2007-11-08 Ali Mostafazadeh