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This review provides a gentle introduction to one-way quantum computing in distributed architectures. One-way quantum computation shows significant promise as a computational model for distributed systems, particularly those architectures…

Quantum Physics · Physics 2010-07-12 Earl T. Campbell , Joseph Fitzsimons

On the basis of the explicit formulae for the action of the unitary group of exponentials corresponding to almost solvable extensions of a given closed symmetric operator with equal deficiency indices, we derive a new representation for the…

Spectral Theory · Mathematics 2018-05-21 Kirill D. Cherednichenko , Alexander V. Kiselev , Luis O. Silva

The purpose of this article is to give a short introduction to the concept of quasi-unitary equivalence of quadratic forms and its consequences. In particular, we improve an estimate concerning the transitivity of quasi-unitary equivalence…

Spectral Theory · Mathematics 2025-03-31 Olaf Post , Jan Simmer

In this work we explore the structure of the branching graph of the unitary group using Schur transitions. We find that these transitions suggest a new combinatorial expression for counting paths in the branching graph. This formula, which…

High Energy Physics - Theory · Physics 2016-09-21 Pablo Diaz , Garreth Kemp , Alvaro Veliz-Osorio

We use functional methods to compute one-loop effects in Heavy Quark Effective Theory. The covariant derivative expansion technique facilitates the efficient extraction of matching coefficients and renormalization group evolution equations.…

High Energy Physics - Phenomenology · Physics 2020-07-15 Timothy Cohen , Marat Freytsis , Xiaochuan Lu

The factorized form of the unitary coupled cluster ansatz is a popular state preparation ansatz for electronic structure calculations of molecules on quantum computers. It often is viewed as an approximation (based on the Trotter product…

Chemical Physics · Physics 2022-02-16 Jia Chen , Hai-Ping Cheng , J. K. Freericks

We develop a comprehensive theory of phase for finite-dimensional quantum systems. The only physical requirement we impose is that phase is complementary to amplitude. To implement this complementarity we use the notion of mutually unbiased…

Quantum Physics · Physics 2009-10-16 A. B. Klimov , L. L. Sanchez-Soto , H. de Guise

We introduce a new technique for solving uni-parametric versions of linear programs, convex quadratic programs, and linear complementarity problems in which a single parameter is permitted to be present in any of the input data. We…

Optimization and Control · Mathematics 2022-03-25 Nathan Adelgren

We consider dual unitary operators and their multi-leg generalizations that have appeared at various places in the literature. These objects can be related to multi-party quantum states with special entanglement patterns: the sites are…

Quantum Physics · Physics 2022-10-25 Márton Mestyán , Balázs Pozsgay , Ian M. Wanless

The availability of a reliable bound on an integral involving the square of the modulus of a form factor on the unitarity cut allows one to constrain the form factor at points inside the analyticity domain and its shape parameters, and also…

High Energy Physics - Phenomenology · Physics 2012-07-25 B. Ananthanarayan , Irinel Caprini

We present a number of quantum computing patterns that build on top of fundamental algorithms, that can be applied to solving concrete, NP-hard problems. In particular, we introduce the concept of a quantum dictionary as a summation of…

The problem of the estimation of multiple phases (or of commuting unitaries) is considered. This is a sub-model of the estimation of a completely unknown unitary operation where it has been shown in recent works that there are considerable…

Quantum Physics · Physics 2007-05-23 Manuel A. Ballester

One-way measurement based quantum computations (1WQC) may describe unitary transformations, via a composition of CPTP maps which are not all unitary themselves. This motivates the following decision problems: Is it possible to determine…

Quantum Physics · Physics 2009-10-22 Niel de Beaudrap

In this paper, we derive the quadratic formula as a consequence of constructively proving the existence of standard and factored forms for general form real quadratic functions. Emphasis is put on connections to graphing of corresponding…

General Mathematics · Mathematics 2020-10-28 Shawn S. Wirts

In this paper we review a proposed geometrical formulation of quantum mechanics. We argue that this geometrization makes available mathematical methods from classical mechanics to the quantum frame work. We apply this formulation to the…

Mathematical Physics · Physics 2014-11-21 G. Marmo , G. F. Volkert

We show how to construct path integrals for quantum mechanical systems where the space of configurations is a general non-compact symmetric space. Associated with this path integral is a perturbation theory which respects the global…

High Energy Physics - Theory · Physics 2015-06-26 Noah Linden , Malcolm Perry

The classical quadratic Gauss sum can be thought of as an exponential sum attached to a quadratic form on a cyclic group. We introduce an equivariant version of Gauss sum for arbitrary finite quadratic forms, which is an exponential sum…

Number Theory · Mathematics 2017-03-23 Shouhei Ma

In these lectures, I describe the techniques used within the QCD sum rule approach. The basic concepts of the approach are introduced using a simple model of quantum-mechanical oscillator in 2+1 dimensions. Then I discuss their…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. V. Radyushkin

The present chapter [submitted for publication in "Fourier Transforms, Theory and Applications", G. Nikolic (Ed.), InTech (Open Access Publisher), Vienna, 2011] is concerned with the introduction and study of a quadratic discrete Fourier…

Quantum Physics · Physics 2011-05-06 Maurice Robert Kibler

In this paper, we present an overview of the recent developments of functional quantization of stochastic processes, with an emphasis on the quadratic case. Functional quantization is a way to approximate a process, viewed as a…

Probability · Mathematics 2013-04-03 Gilles Pagès