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Sharing correlated random variables is a resource for a number of information theoretic tasks such as privacy amplification, simultaneous message passing, secret sharing and many more. In this article, we show that to establish such a…

Quantum Physics · Physics 2021-11-03 Tamal Guha , Mir Alimuddin , Sumit Rout , Amit Mukherjee , Some Sankar Bhattacharya , Manik Banik

The motion of a composite system made of N particles is examined in a space with a canonical noncommutative algebra of coordinates. It is found that the coordinates of the center-of-mass position satisfy noncommutative algebra with…

General Relativity and Quantum Cosmology · Physics 2015-06-19 Kh. P. Gnatenko

Quantum coherence as the fundamental characteristic of quantum physics, provides the valuable resource for quantum computation in exceeding the power of classical algorithms. The exploration of quantum coherence in relativistic systems is…

Quantum Physics · Physics 2016-01-13 Xu Chen , Chunfeng Wu , Hong-Yi Su , Chang-Liang Ren , Jing-Ling Chen

Quantum computing gates are proposed to apply on trapped ions in decoherence-free states. As phase changes due to time evolution of components with different eigenenergies of quantum superposition are completely frozen, quantum computing…

Quantum Physics · Physics 2009-11-07 Mang Feng , Xiaoguang Wang

We review the recent result of Sato, Sekimoto, Hondou, and Takagi (cond-mat/0008393) on the irreversibility inevitably observed in systems consisting of many non-interacting ``small'' pieces. We focus on quantum models, and supply an…

Statistical Mechanics · Physics 2007-05-23 Hal Tasaki

In the context of constrained quantum mechanics, reference systems are used to construct relational observables that are invariant under the action of the symmetry group. Upon measurement of a relational observable, the reference system…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Florian Girelli , David Poulin

We study the dynamics of correlations in a paradigmatic setup to observe $\mathcal{PT}$-symmetric physics: a pair of coupled oscillators, one subject to a gain one to a loss. Starting from a coherent state, quantum correlations (QCs) are…

For years, the quantum/reversible circuit community has been convinced that: a) the addition of auxiliary qubits is instrumental in constructing a smaller quantum circuit; and, b) the introduction of quantum gates inside reversible circuits…

Quantum Physics · Physics 2011-08-01 Dmitri Maslov , Mehdi Saeedi

Many promising quantum algorithms in economics, medical science, and material science rely on circuits that are parameterized by a large number of angles. To ensure that these algorithms are efficient, these parameterized circuits must be…

Quantum Physics · Physics 2025-07-09 Neil J. Ross , Scott Wesley

It is known that one can do quantum error correction without syndrome measurement, which is often done in operator quantum error correction (OQEC). However, the physical realization could be challenging, especially when the recovery process…

Quantum Physics · Physics 2013-04-11 Chi-Kwong Li , Mikio Nakahara , Yiu-Tung Poon , Nung-Sing Sze , Hiroyuki Tomita

A novel interpretation of the quantum mechanical superposition is put forward. Quantum systems scan all possible available states and switch randomly and very rapidly among them. The longer they remain in a given state, the larger the…

General Physics · Physics 2016-05-31 Beatriz Gato-Rivera

We extend integrable systems on quad-graphs, such as the Hirota equation and the cross-ratio equation, to the non-commutative context, when the fields take values in an arbitrary associative algebra. We demonstrate that the…

Exactly Solvable and Integrable Systems · Physics 2007-06-13 A. I. Bobenko , Yu. B. Suris

Quantum systems are by their very nature fragile. The fundamental backaction on a state due to quantum measurement notwithstanding, there is also in practice often a destruction of the system itself due to the means of measurement. This…

Quantum Physics · Physics 2023-09-12 Thomas J. Elliott , Mile Gu , Jayne Thompson , Nana Liu

The aim of this paper is to propose a criterion of spontaneous symmetry breaking that makes reference to the properties of pure phases defined by a translationally invariant state. By avoiding any reference to the ground state, at the basis…

Statistical Mechanics · Physics 2020-07-08 Carlo Heissenberg , Franco Strocchi

The parameter-shift rule is an approach to measuring gradients of quantum circuits with respect to their parameters, which does not require ancilla qubits or controlled operations. Here, I discuss applying this approach to a wider range of…

Quantum Physics · Physics 2019-06-03 Gavin E. Crooks

Quantum addition based on the quantum Fourier transform can be an integral part of a quantum circuit and proved to be more efficient than the existing classical ripple carry adder. Our study includes identifying the quantum resource…

A spontaneous symmetry breaking mechanism is used in quantum gravity to obtain a convergent positive definite density-matrix as the most general quantum state of Euclidean wormholes

General Relativity and Quantum Cosmology · Physics 2011-04-20 Pedro F. Gonzalez-Diaz

Effective state transfer is one of the most important problems in quantum information processing. Typically, a quantum information device is composed of many subsystems with multi-input ports. In this paper, we develop a general theory…

Quantum Physics · Physics 2016-08-23 Naoki Yamamoto , Hendra I. Nurdin , Matthew R. James

Free fall in a uniform gravitational field is revisited in the case of quantum states with and without classical analogue. The interplay between kinematics and dynamics in the evolution of a falling quantum test particle is discussed…

Quantum Physics · Physics 2009-12-30 Lorenza Viola , Roberto Onofrio

The implementation of physical symmetries into problem descriptions allows for the reduction of parameters and computational complexity. We show the integration of the permutation symmetry as the most restrictive discrete symmetry into…