English
Related papers

Related papers: Causal evolution of wave packets

200 papers

For autonomous systems it is well known how to extract tunneling probabilities from wavepacket calculations. Here we present a corresponding approach for periodically time-dependent Hamiltonians, valid at all frequencies, field strengths,…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 Frank Grossmann

We prove that the classical Dirac equation in the presence of an external (nondynamical) electromagnetic field is a relativistically causal theory. As a corollary, we show that it is impossible to use quantum tunneling to transmit particles…

Quantum Physics · Physics 2023-03-14 Lorenzo Gavassino , Marcelo M. Disconzi

We construct a model of cooperative superradiant emission from a highly relativistic multi-particle source. We revise an existing model of the literature for a relativistic two-level particle, and construct from it a Hamiltonian describing…

Quantum Physics · Physics 2023-01-18 Christopher Wyenberg , Fereshteh Rajabi , Martin Houde

In this article we present an exact and unified description of wave-packet dynamics in various 2D systems in presence of a transverse magnetic field. We consider an initial minimum-uncertainty Gaussian wave-packet, and find that its long…

Mesoscale and Nanoscale Physics · Physics 2015-03-19 Ashutosh Singh , Tutul Biswas , Tarun Kanti Ghosh , Amit Agarwal

A solution of the Dirac equation in a strong laser field presenting a nonspreading wave packet in the rest frame of the electron is derived. It consists of a generalization of the self-accelerating free electron wave packet [Kaminer et al.…

Quantum Physics · Physics 2023-10-16 Andre G. Campos , Karen Z. Hatsagortsyan , Christoph H. Keitel

We present a new causal quantum mechanics in one and two dimensions developed recently at TIFR by this author and V. Singh. In this theory both position and momentum for a system point have Hamiltonian evolution in such a way that the…

Quantum Physics · Physics 2009-10-31 S. M. Roy

This article investigates some solutions of the time-dependent free Dirac equation. Visualizations of these solutions immediately reveal strange phenomena that are caused by the interference of positive- and negative-energy waves. The…

Quantum Physics · Physics 2007-05-23 Bernd Thaller

An explanation for superluminal phenomena based on wave-particle duality of photons is suggested. A single photon may be regarded as a wave packet, whose spatial extension is its coherence volume. As a photon propagates as a wave train in…

Quantum Physics · Physics 2024-03-15 Hai-Long Zhao

The central limit theorem has been found to apply to random vectors in complex Hilbert space. This amounts to sufficient reason to study the complex valued Gaussian, looking for relevance to quantum mechanics. Here we show that the…

Quantum Physics · Physics 2020-03-13 P. M. Grinwald

By introducing the concepts of "superclassicality" and "relational causality", it is shown here that the velocity field emerging from an n-slit system can be calculated as an average classical velocity field with suitable weightings per…

Quantum Physics · Physics 2014-09-30 Gerhard Groessing , Siegfried Fussy , Johannes Mesa Pascasio , Herbert Schwabl

We develop relativistic causality theory in the setting of point-free topology by introducing a notion of causal coverage in ordered locales, generalising their canonical coverage relation to incorporate causal structure. This improves…

Mathematical Physics · Physics 2025-10-21 Chris Heunen , Nesta van der Schaaf

In the context of nonrelativistic quantum mechanics, Gaussian wavepacket solutions of the time-dependent Schr\"odinger equation provide useful physical insight. This is not the case for relativistic quantum mechanics, however, for which…

Quantum Physics · Physics 2016-05-06 Hung-Ming Tsai , Bill Poirier

The motion of a particle is studied in a random space-time. It is assumed that the velocity is small enough for the non-relativistic approximation to be valid. The randomness of the metric induces a diffusion in coordinate space. Hence it…

Quantum Physics · Physics 2009-11-11 Emilio Santos

We study the anomalous transport in systems of random walks (RW's) on comb-like lattices with fractal sidebranches, showing subdiffusion, and in a system of Brownian particles driven by a random shear along the x-direction, showing a…

Statistical Mechanics · Physics 2022-06-15 Fabio Cecconi , Giulio Costantini , Alessandro Taloni , Angelo Vulpiani

We study propagation of high-frequency wave packets along a large-scale background wave which evolves according to dispersionless hydrodynamic equations for two variables (fluid density and flow velocity). Influence of the wave packet on…

Pattern Formation and Solitons · Physics 2023-06-08 D. V. Shaykin , A. M. Kamchatnov

We study numerically the evolution of wavepackets in quasi one-dimensional random systems described by a tight-binding Hamiltonian with long-range random interactions. Results are presented for the scaling properties of the width of packets…

Condensed Matter · Physics 2009-10-28 F. M. Izrailev , T. Kottos , A. Politi , G. P. Tsironis

Time evolution of radial wave packets built from the eigenstates of Dirac equation for a hydrogenic systems is considered. Radial wave packets are constructed from the states of different $n$ quantum number and the same lowest angular…

Quantum Physics · Physics 2007-05-23 M. Turek , P. Rozmej

We investigate relativistic wavepacket dynamics for an electron tunneling through a potential barrier employing space-time resolved solutions to relativistic quantum field theory (QFT) equations. We prove by linking the QFT property of…

Quantum Physics · Physics 2026-03-17 M. Alkhateeb , X. Gutierrez de la Cal , M. Pons , D. Sokolovski , A. Matzkin

The evolution of both quantum and classical ensembles may be described via the probability density P on configuration space, its canonical conjugate S, and an_ensemble_ Hamiltonian H[P,S]. For quantum ensembles this evolution is, of course,…

Quantum Physics · Physics 2009-11-10 Michael J. W. Hall

Collapse of the wave function appears to violate the quantum superposition principle as well as deterministic evolution. Objective collapse models propose a dynamical explanation for this phenomenon, by making a stochastic non-unitary and…

Quantum Physics · Physics 2023-10-27 Kartik Kakade , Avnish Singh , Tejinder P. Singh