English
Related papers

Related papers: Comment on ``Time-dependent quasi-Hermitian Hamilt…

200 papers

We show that quantum circuit complexity for the unitary time evolution operator of any time-independent Hamiltonian is bounded by linear growth at early times, independent of any choices of the fundamental gates or cost metric. Deviations…

High Energy Physics - Theory · Physics 2024-10-15 S. Shajidul Haque , Ghadir Jafari , Bret Underwood

A free hermitian conformal field theory is considered in Minkowski, de Sitter and anti-de Sitter spacetimes. The first part of the paper studies spacetime inversion and conformal inversion, wherein their role in the field quantization is…

General Relativity and Quantum Cosmology · Physics 2015-01-16 Slava Emelyanov

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

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

For a large class of time-dependent non-Hermitain Hamiltonians expressed in terms linear and bilinear combinations of the generators for an Euclidean Lie-algebra respecting different types of PT-symmetries, we find explicit solutions to the…

Quantum Physics · Physics 2019-01-17 Andreas Fring , Thomas Frith

The existence of a hermitian time operator is proposed in the framework of non-relativistic quantum mechanics.The Heisenberg equation of motion is shown to yield constant rate of flow of time.It is shown to yield results consistent with…

Quantum Physics · Physics 2015-07-21 Carringtone Kinyanjui , Dismas Simiyu Wamalwa

In this work we construct an approximate time evolution operator for a system composed by two coupled Jaynes-Cummings Hamiltonians. We express the full time evolution operator as a product of exponentials and we analyze the validity of our…

Quantum Physics · Physics 2022-06-20 I. Ramos-Prieto , A. Paredes , J. Récamier , H. Moya-Cessa

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

Evolutions under non-Hermitian Hamiltonians with unbroken $\mathcal{PT}$ symmetry can be considered unitary under appropriate choices of inner products, facilitated by the so-called metric operator. While it is understood that the choice of…

Quantum Physics · Physics 2025-12-04 Himanshu Badhani , C. M. Chandrashekar

This paper is the third part concluding the introduction of the powerful algebra of the pseudo-observables. In this article will be dealt how to treat the time evolution, and, more in general, the transformations, in the framework of the…

Quantum Physics · Physics 2017-08-18 Edoardo Piparo

All covariant time operators with normalized probability distribution are derived. Symmetry criteria are invoked to arrive at a unique expression for a given Hamiltonian. As an application, a well known result for the arrival time…

Quantum Physics · Physics 2015-05-19 G. C. Hegerfeldt , J. G. Muga

Given a quantum Hamiltonian and its evolution time, the corresponding unitary evolution operator can be constructed in many different ways, corresponding to different trajectories between the desired end-points and different series…

Quantum Physics · Physics 2017-03-14 Apoorva Patel , Anjani Priyadarsini

Many-mode Floquet theory [T.-S. Ho, S.-I. Chu, and J. V. Tietz, Chem. Phys. Lett., v. 96, 464 (1983)] is a technique for solving the time-dependent Schr\"odinger equation in the special case of multiple periodic fields, but its limitations…

Quantum Physics · Physics 2020-04-01 A. N. Poertner , J. D. D. Martin

Given a quantum Hamiltonian and its evolution time, the corresponding unitary evolution operator can be constructed in many different ways, corresponding to different trajectories between the desired end-points. A choice among these…

Quantum Physics · Physics 2015-03-05 Apoorva Patel

We put forth the idea that Hamilton's equations coincide with deterministic and reversible evolution. We explore the idea from five different perspectives (mathematics, measurements, thermodynamics, information theory and state mapping) and…

Classical Physics · Physics 2013-08-05 Gabriele Carcassi

The Chebyshev expansion method is a well-established technique for computing the time evolution of quantum states, particularly in Hermitian systems with a bounded spectrum. Here, we show that the applicability of the Chebyshev expansion…

Mesoscale and Nanoscale Physics · Physics 2025-10-14 Áron Holló , Dániel Varjas , Cosma Fulga , László Oroszlány , Viktor Könye

We present efficient quantum algorithms for simulating time-dependent Hamiltonian evolution of general input states using an oracular model of a quantum computer. Our algorithms use either constant or adaptively chosen time steps and are…

Quantum Physics · Physics 2011-11-03 Nathan Wiebe , Dominic W. Berry , Peter Hoyer , Barry C. Sanders

Phenomenological studies of quantum gravity have proposed a modification of the commutator between position and momentum in quantum mechanics so to introduce a minimal uncertainty in position in quantum mechanics. Such a minimal uncertainty…

General Relativity and Quantum Cosmology · Physics 2023-02-10 Pasquale Bosso

We continue the study of time-dependent Hamiltonians with an isolated singularity in their time dependence, describing propagation on singular space-times. In previous work, two of us have proposed a "minimal subtraction" prescription for…

High Energy Physics - Theory · Physics 2014-11-18 Ben Craps , Frederik De Roo , Oleg Evnin

We analyze the issue of dynamical evolution and time in quantum cosmology. We emphasize the problem of choice of phase space variables that can play the role of a time parameter in such a way that for expectation values of quantum operators…

General Relativity and Quantum Cosmology · Physics 2021-07-05 Alexander Yu. Kamenshchik , Jeinny Nallely Perez Rodriguez , Tereza Vardanyan