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Elementary Cycles Theory is a self-consistent, unified formulation of quantum and relativistic physics. Here we introduce its basic quantum aspects. On one hand, Newton's law of inertia states that every isolated particle has persistent…

General Physics · Physics 2021-09-21 Donatello Dolce

An extension of standard quantum mechanics is proposed in which the Newtonian time appearing as a parameter in the unitary evolution operator is replaced with the time shown by a `quantum clock'. Such a clock is defined by the following…

Quantum Physics · Physics 2026-03-17 Dorje C. Brody , Lane P. Hughston

The time evolution of an unstable quantum mechanical system coupled with an external measuring agent is investigated. According to the features of the interaction Hamiltonian, a quantum Zeno effect (hindered decay) or an inverse quantum…

Quantum Physics · Physics 2010-01-31 P. Facchi , S. Pascazio

The interaction between two parts in a compound quantum system may be reconsidered more completely than before and some new understandings and conclusions different from current quantum mechanics are obtained, including the conservation law…

General Physics · Physics 2010-11-03 Tian-Hai Zeng

A realist description of our universe requires a twofold concept of locality. On one hand, there are the strictly Einstein-local interactions which generate the time evolution. On the other hand, the quantum state space calls for a…

Quantum Physics · Physics 2013-08-27 Andreas O. Tell

The evolution of a quantum system undergoing very frequent measurements takes place in a proper subspace of the total Hilbert space (quantum Zeno effect). When the measuring apparatus is included in the quantum description, the Zeno effect…

Quantum Physics · Physics 2017-08-23 P. Facchi

From the time dependence of states of one of them, the dynamics of two interacting qubits is determined to be one of two possibilities that differ only by a change of signs of parameters in the Hamiltonian. The only exception is a simple…

Quantum Physics · Physics 2009-11-13 Thomas F. Jordan , Anil Shaji , E. C. G. Sudarshan

We analize the relational quantum evolution of generally covariant systems in terms of Rovelli's evolving constants of motion and the generalized Heisenberg picture. In order to have a well defined evolution, and a consistent quantum…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Rodolfo Gambini , Rafael A. Porto

We study the behavior of Quantum Darwinism (Zurek, [8]) within the iterative, random unitary operations qubit-model of pure decoherence (Novotny et al, [6]). We conclude that Quantum Darwinism, which describes the quantum mechanical…

Quantum Physics · Physics 2015-10-09 Nenad Balaneskovic

Time evolution generically entangles a quantum state with environmental degrees of freedom. The resulting increase in entropy changes the properties of that quantum system leading to "aging". It is interesting to ask if this familiar…

Quantum Physics · Physics 2022-06-08 Mark G. Raizen , David E. Kaplan , Surjeet Rajendran

If there exists a classical, i.e. deterministic theory underlying quantum mechanics, an explanation must be found of the fact that the Hamiltonian, which is defined to be the operator that generates evolution in time, is bounded from below.…

Quantum Physics · Physics 2009-11-13 Gerard 't Hooft

The Nelson stochastic mechanics is derived as a consequence of the basic physical principles such as the principle of relativity of observations and the invariance of the action quantum. The unitary group of quantum mechanics is represented…

High Energy Physics - Theory · Physics 2012-10-09 Zahid Zakir

In the present work, a new time-dependent exchange theory is presented wherein the symmetry constraints, on a multi-electron wavefunction, are properly accounted for. In so doing, the equations of motion, incorporating the required…

Computational Physics · Physics 2007-05-23 Charles A. Weatherford

The "speed" of unitary quantum evolution was recently shown to be connected to entanglement in multipartite quantum systems. Here, we discuss a tighter version of the Mandelstam-Tamm uncertainty relation that depends on the Fisher…

Quantum Physics · Physics 2012-06-01 Florian Fröwis

The quantum Zeno effect consists in the hindrance of the evolution of a quantum system that is very frequently monitored and found to be in its initial state at every single measurement. On the basis of the correct formula for the survival…

Quantum Physics · Physics 2009-10-30 Hiromichi Nakazato , Mikio Namiki , Saverio Pascazio , Helmut Rauch

We consider a quantum system strongly driven by forces that are periodic in time. The theorem concerns the probability $P(e)$ of observing a given energy change $e$ after a number of cycles. If the system is thermostated by a (quantum)…

Statistical Mechanics · Physics 2016-08-31 Jorge Kurchan

Time evolution of a perturbed thermal state is studied in a quantum-mechanical system with O(N) symmetry. In the limit of large N, time dependence of O(N)-singlet expectation values can be described by classical equations of motion in a…

Quantum Physics · Physics 2009-03-26 P. V. Buividovich

Under broad conditions, we prove that the probability amplitudes in the quantum mechanics are either always constant in time or changing continuously in any interval of time.

Quantum Physics · Physics 2018-05-17 M. A. Rajabpour

The loss of time-translational invariance caused by a time-dependent external agent leads to particle creation effects in quantum field theory. This phenomenon results in ambiguities when selecting the quantum vacuum of the canonical…

High Energy Physics - Theory · Physics 2022-06-24 Álvaro Álvarez-Domínguez , Luis J. Garay , Mercedes Martín-Benito

A modification of the covariant theory is proposed in which the self-energy of the system, corresponding to time-like degrees of freedom in the configuration space, preserves the classical law of change in quantum theory. As a result,…

General Relativity and Quantum Cosmology · Physics 2020-01-27 Natalia Gorobey , Alexander Lukyanenko