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Related papers: Some Remarks on Quantum Brachistochrone

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In this paper, we study quantitative properties of quantum programs. Properties of interest include (positive) almost-sure termination, expected runtime or expected cost, that is, for example, the expected number of applications of a given…

Logic in Computer Science · Computer Science 2023-12-22 Martin Avanzini , Georg Moser , Romain Péchoux , Simon Perdrix

The discussion of the foundations of quantum mechanics is complicated by the fact that a number of different issues are closely entangled. Three of these issues are i) the interpretation of probability, ii) the choice between realist and…

Quantum Physics · Physics 2017-08-23 Willem M. de Muynck

The efficient certification of classically intractable quantum devices has been a central research question for some time. However, to observe a "quantum advantage", it is believed that one does not need to build a large scale universal…

Quantum Physics · Physics 2018-03-05 Daniel Mills , Anna Pappa , Theodoros Kapourniotis , Elham Kashefi

A practical way to deal with the problem of time in quantum cosmology and quantum gravity is proposed. The main tool is effective equations, which mainly restrict explicit considerations to semiclassical regimes but have the crucial…

General Relativity and Quantum Cosmology · Physics 2011-07-20 Martin Bojowald , Philipp A Hoehn , Artur Tsobanjan

In the context of the current lack of compatibility of the classical and quantum approaches to gravity, exactly solvable elementary pseudo-Hermitian quantum models are analyzed supporting the acceptability of a point-like form of Big Bang.…

General Relativity and Quantum Cosmology · Physics 2025-06-23 Miloslav Znojil

While seemingly undesirable, it is not a surprising fact that there are certain problems for which quantum computers offer no computational advantage over their respective classical counterparts. Moreover, there are problems for which there…

Quantum Physics · Physics 2025-07-16 Yanlin Chen , Yilei Chen , Rajendra Kumar , Subhasree Patro , Florian Speelman

Quantum computer algorithms can exploit the structure of random satisfiability problems. This paper extends a previous empirical evaluation of such an algorithm and gives an approximate asymptotic analysis accounting for both the average…

Quantum Physics · Physics 2007-05-23 Tad Hogg

We analyze some features of alternative Hermitian and quasi-Hermitian quantum descriptions of simple and bipartite compound systems. We show that alternative descriptions of two interacting subsystems are possible if and only if the metric…

Quantum Physics · Physics 2011-06-24 G. Scolarici , L. Solombrino

We introduce generalized versions of complex Scarf and Morse-type potentials that con- tain energy-dependent parameters. PT -symmetry and pseudo-hermiticity of the associated quantum systems are discussed, and a modified orthogonality…

Mathematical Physics · Physics 2017-04-26 Axel Schulze-Halberg , Pinaki Roy

We give a condition for an almost constant-type manifold to be a constant-type manifold, and holomorphic and $R$-invariant submanifolds of almost Hermitian manifolds are studied. Generalizations of some results in [5] are given.

Differential Geometry · Mathematics 2013-11-12 Hakan Mete Taştan

Quantum logic gates provide fundamental examples of conditional quantum dynamics. They could form the building blocks of general quantum information processing systems which have recently been shown to have many interesting non--classical…

Quantum Physics · Physics 2009-10-28 A. Barenco , D. Deutsch , A. Ekert , R. Jozsa

The non-Hermitian Schr\"odinger equation is re-expressed generally in the form of Hamilton's canonical equation without any approximation. Its quantization called non-Hermitian quantum field theory is discussed. By virtue of the canonical…

Quantum Physics · Physics 2020-05-22 Qi Zhang

To date, quantum mechanics has proven to be our most successful theoretical model. However, it is still surrounded by a "mysterious halo" that can be summarized in a simple but challenging question: Why quantum phenomena are not understood…

History and Philosophy of Physics · Physics 2015-08-18 A. S. Sanz

We investigate the idea that different interpretations of quantum mechanics can be seen as restrictions of the consistent (or decoherent) histories quantum mechanics of closed systems to particular classes of histories,together with the…

Quantum Physics · Physics 2014-11-18 James B. Hartle

A series of recent papers ``Faster than Hermitian Quantum Mechanics'' and related articles made a point of the possibility of a non-Hermitian, but PT-symmetric, operator to play the role of a Hamiltonian. In particular, they show that with…

Quantum Physics · Physics 2008-04-15 Mark J. Everitt , Shaaban Khalil , Alexandre M. Zagoskin

Quantum computers hold great promise, but it remains a challenge to find efficient quantum circuits that solve interesting computational problems. We show that finding optimal quantum circuits is essentially equivalent to finding the…

Quantum Physics · Physics 2009-11-13 Michael A. Nielsen , Mark R. Dowling , Mile Gu , Andrew C. Doherty

We present a quantum solution to coordination problems that can be implemented with present technologies. It provides an alternative to existing approaches, which rely on explicit communication, prior commitment or trusted third parties.…

Quantum Physics · Physics 2015-01-23 Bernardo A. Huberman , Tad Hogg

Variational quantum circuits (VQCs) are a central component of many quantum machine learning algorithms, offering a hybrid quantum-classical framework that, under certain aspects, can be considered similar to classical deep neural networks.…

Quantum Physics · Physics 2025-07-16 Nicola Assolini , Luca Marzari , Isabella Mastroeni , Alessandra di Pierro

Quantum brachistochrone method has recently emerged as a technique allowing one to implement the desired unitary evolution operator in a physical system within the minimal time. Here, we apply this approach to the problem of time-optimal…

Mesoscale and Nanoscale Physics · Physics 2025-06-10 Kseniia S. Chernova , Andrei A. Stepanenko , Maxim A. Gorlach

We revise the problem of the quantization of relativistic particle, presenting a modified consistent canonical scheme, which allows one not only to include arbitrary backgrounds in the consideration but to get in course of the quantization…

High Energy Physics - Theory · Physics 2010-04-06 S. P. Gavrilov , D. M. Gitman