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The problem of time in quantum mechanics concerns the fact that in the Schr\"odinger equation time is a parameter, not an operator. Pauli's objection to a time-energy uncertainty relation analogue to the position-momentum one, conjectured…

Quantum Physics · Physics 2017-04-05 M. Bauer

We present a general theory to quantify the uncertainty from imposing structural assumptions on the second-order structure of nonstationary Hilbert space-valued processes, which can be measured via functionals of time-dependent spectral…

Statistics Theory · Mathematics 2023-09-19 Anne van Delft , Holger Dette

Compared with time independent Hamiltonians, the dynamics of generic quantum Hamiltonians $H(t)$ are complicated by the presence of time ordering in the evolution operator. In the context of digital quantum simulation, this difficulty…

Quantum Physics · Physics 2024-04-08 Jacob Watkins , Nathan Wiebe , Alessandro Roggero , Dean Lee

With the aim to solve the time-dependent Schr\"{o}dinger equation associated to a time-dependent non-Hermitian Hamiltonian, we introduce a unitary transformation that maps the Hamiltonian to a time-independent $\mathcal{PT}$-symmetric one.…

Quantum Physics · Physics 2021-12-28 F. Kecita , A. Bounames , M. Maamache

We know that space and time are treated almost equally in classical physics, but we also know that this is not the case for quantum mechanics. A quantum description of both space and time is important to really understand the quantum nature…

Quantum Physics · Physics 2024-02-20 Ngo Phuc Duc Loc

In this work we will advance farther along a line previously developed concerning our proposal of a time interval operator, on finite dimensional spaces. The time interval operator is Hermitian, and its eigenvalues are time values with a…

Quantum Physics · Physics 2007-05-23 M. Ruzzi , D. Galetti

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

Quantum gravity is expected to contain descriptions of semiclassical spacetime geometries in quantum superpositions. To date, no framework for modelling such superpositions has been devised. Here, we provide a new phenomenological…

General Relativity and Quantum Cosmology · Physics 2021-05-11 Joshua Foo , Robert B. Mann , Magdalena Zych

The problem of existence of a self-adjoint time operator conjugate to a Hamiltonian with SU(1,1) dynamical symmetry is investigated. In the space spanned by the eigenstates of the generator $K_3$ of the SU(1,1) group, the time operator for…

Quantum Physics · Physics 2007-05-23 M. Martinis , V. Mikuta

In the quantum theory, it has been shown that one can see if a process has the time reversal symmetry by applying the matrix transposition and examining if it remains physical. However, recent discoveries regarding the indefinite causal…

Quantum Physics · Physics 2023-06-29 Seok Hyung Lie , M. S. Kim

We consider sample to sample fluctuations of the waiting time between the detection of two consecutive electrons in quasi-one-dimensional disordered conductors at zero temperature. We compute the full distribution of the mean waiting time…

Mesoscale and Nanoscale Physics · Physics 2024-07-24 Ferdinand Schulz , Mathias Albert

We study the non equilibrium time evolution of an integrable field theory in 1+1 dimensions after a sudden variation of a global parameter of the Hamiltonian. For a class of quenches defined in the text, we compute the long times limit of…

Statistical Mechanics · Physics 2010-12-02 Davide Fioretto , Giuseppe Mussardo

We describe the time evolution of quantum systems in a classical background space-time by means of a covariant derivative in an infinite dimensional vector bundle. The corresponding parallel transport operator along a timelike curve $\cC$…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Dirk Graudenz

Time of arrival in quantum mechanics is discussed in two versions: the classical axiomatic "time of arrival operator" introduced by J. Kijowski and the EEQT method. It is suggested that for free particles the two methods may lead to the…

Quantum Physics · Physics 2014-07-22 Arkadiusz Jadczyk

Both unitary evolution and the effects of dissipation and decoherence for a general three-level system are of widespread interest in quantum optics, molecular physics, and elsewhere. A previous paper presented a technique for solving the…

Quantum Physics · Physics 2008-11-26 A. R. P. Rau , Weichang Zhao

We consider an isolated autonomous quantum machine, where an explicit quantum clock is responsible for performing all transformations on an arbitrary quantum system (the engine), via a time-independent Hamiltonian. In a general context, we…

Quantum Physics · Physics 2015-06-30 Artur S. L. Malabarba , Anthony J. Short , Philipp Kammerlander

Quantum mechanics rests on the assumption that time is a classical variable. As such, classical time is assumed to be measurable with infinite accuracy. However, all real clocks are subject to quantum fluctuations, which leads to the…

General Relativity and Quantum Cosmology · Physics 2008-11-26 J. M. Isidro , J. L. Gonzalez-Santander , P. Fernandez de Cordoba

In order to resolve the measurement problem of Quantum Mechanics, non-unitary time evolution has been derived from the unitarity of standard quantum formalism. New wave functions of free and non-free quantum systems follow from Schroedinger…

Quantum Physics · Physics 2007-05-23 Pradip Kumar Chatterjee

Ever since Schrodinger, Time in quantum theory is postulated Newtonian for every reference frame. With the help of certain known mathematical results, we show that the concept of the so-called Local Time allows avoiding the postulate. In…

Quantum Physics · Physics 2016-10-26 H. Kitada , J. Jeknic-Dugic , M. Arsenijevic , M. Dugic

The accuracy of quantum dynamics simulation is usually measured by the error of the unitary evolution operator in the operator norm, which in turn depends on certain norm of the Hamiltonian. For unbounded operators, after suitable…

Quantum Physics · Physics 2021-05-26 Dong An , Di Fang , Lin Lin