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Related papers: Quantum tunneling from paths in complex time

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Classical machine learning theory and theory of quantum computations are among of the most rapidly developing scientific areas in our days. In recent years, researchers investigated if quantum computing can help to improve classical machine…

Quantum Physics · Physics 2019-06-26 D. V. Fastovets , Yu. I. Bogdanov , B. I. Bantysh , V. F. Lukichev

In recent years efficient algorithms have been developed for the numerical computation of relativistic single-particle path integrals in quantum field theory. Here, we adapt this "worldline Monte Carlo" approach to the standard problem of…

A generalization of classical mechanics is obtained from a complex parametrization of the phase space. The formalism supports complex Hamiltonian functions describing non-conservative classical mechanical systems. A quantization scheme that…

Quantum Physics · Physics 2025-03-25 Sergio Giardino

The tunneling wave function of the universe is investigated in a minisuperspace framework of a de Sitter universe with a quantum scalar field, treated as a perturbation. We consider three different approaches to defining the tunneling wave…

General Relativity and Quantum Cosmology · Physics 2018-09-19 Alexander Vilenkin , Masaki Yamada

We investigate in detail the properties of oscillating instanton solutions discussed recently in the literature. We find that the solutions with N nodes contain exactly N homogeneous negative modes in their spectrum of linear perturbations.…

High Energy Physics - Theory · Physics 2013-05-30 Lorenzo Battarra , George Lavrelashvili , Jean-Luc Lehners

We consider a range of unconventional modifications to Quantum Annealing (QA), applied to an artificial trial problem with continuously tunable difficulty. In this problem, inspired by "transverse field chaos" in larger systems, classical…

Quantum Physics · Physics 2021-03-31 Zhijie Tang , Eliot Kapit

Quantum walks, the quantum mechanical counterpart of classical random walks, is an advanced tool for building quantum algorithms that has been recently shown to constitute a universal model of quantum computation. Quantum walks is now a…

Quantum Physics · Physics 2012-10-01 Salvador E. Venegas-Andraca

Following our work [Phys. Rev. Lett. 125, 020401 (2020)], we discuss a semiclassical description of one-dimensional quantum tunneling through multibarrier potentials in terms of complex time. We start by defining a complex-extended…

Quantum Physics · Physics 2021-06-09 Pavel Stránský , Milan Šindelka , Pavel Cejnar

We describe our recent proposal of a path integral formulation of classical Hamiltonian dynamics. Which leads us here to a new attempt at hybrid dynamics, which concerns the direct coupling of classical and quantum mechanical degrees of…

Quantum Physics · Physics 2011-07-11 H-T Elze , G Gambarotta , F Vallone

Tunneling, transport of particles through classically forbidden regions, is a pure quantum phenomenon. It governs numerous phenomena ranging from single-molecule electronics to donor-acceptor transition reactions. The main problem is the…

Quantum Physics · Physics 2017-10-13 Durmus Demir , Tugrul Guner

Tunneling times in atomic ionization are studied theoretically by a virtual detector approach. A virtual detector is a hypothetical device that allows one to monitor the wave function's density with spatial and temporal resolution during…

Quantum Physics · Physics 2016-08-10 Nicolas Teeny , Christoph H. Keitel , Heiko Bauke

The quantum decay of a metastable vacuum is exponentially suppressed by a tunneling action that can be calculated in the semi-classical approximation as the Euclidean action of a bounce that interpolates between the false and true phases.…

High Energy Physics - Theory · Physics 2019-02-13 José Ramón Espinosa , Thomas Konstandin

The coherent manipulation of quantum states is one of the main tasks required in quantum computation. In this paper we demonstrate that it is possible to control coherently the electronic position of a particle in a quantum-dot array. By…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 J. M. Villas-Boas , Sergio E. Ulloa , Nelson Studart

In the absence of gravity, one can prove that tunnelling instantons exhibit exactly one negative mode in their spectrum of fluctuations. It is precisely the existence of this tunnelling negative mode that warrants an interpretation of these…

High Energy Physics - Theory · Physics 2015-07-15 Michael Koehn , George Lavrelashvili , Jean-Luc Lehners

We study the Schwinger effect, in which the external field having a spatiotemporal profile creates electron-positron pairs via multidimensional quantum tunneling. Our treatment is based on the trace formula for the QED effective action,…

High Energy Physics - Theory · Physics 2016-04-13 Cesim K. Dumlu

Tunneling is an important physical process. The observation that particles surmount a high mountain in spite of the fact that they don't have the necessary energy cannot be explained by classical physics. However, this so called tunneling…

Quantum Physics · Physics 2009-11-13 G. Nimtz , A. A. Stahlhofen

Continuously self-similar solution of spherically symmetric gravitational collapse of a scalar field is studied to investigate quantum mechanical black hole formation by tunneling in the subcritical case where, classically, the collapse…

General Relativity and Quantum Cosmology · Physics 2010-11-19 Dongsu Bak , Sang Pyo kim , Sung Ku Kim , Kwang-Sup Soh , Jae Hyung Yee

To solve the quantum-mechanical problem the procedure of mapping onto linear space $W$ of generators of the (sub)group violated by given classical trajectory is formulated. The formalism is illustrated by the plane H-atom model. The problem…

High Energy Physics - Theory · Physics 2007-05-23 J. Manjavidze

We describe in detail a physical situation in which instantons are necessarily complex, not just Wick rotations of classical solutions to Euclidean spacetime. These complex instantons arise in the semiclassical evaluation of vacuum pair…

High Energy Physics - Theory · Physics 2012-05-15 Cesim K. Dumlu , Gerald V. Dunne

We present an analytical solution for the tunneling process in a piecewise linear and quadratic potential which does not make use of the thin-wall approximation. A quadratic potential allows for smooth attachment of various slopes exiting…

High Energy Physics - Theory · Physics 2015-07-24 Koushik Dutta , Pascal M. Vaudrevange , Alexander Westphal
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