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Related papers: Closed timelike curves in measurement-based quantu…

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We consider causality respecting (CR) quantum systems interacting with closed timelike curves (CTCs), within the Deutsch model. We introduce the concepts of popping up and elimination of quantum information and use them to show that…

Quantum Physics · Physics 2018-07-17 Asutosh Kumar , Indranil Chakrabarty , Arun Kumar Pati , Aditi Sen De , Ujjwal Sen

We prove that one-way quantum computations have the same computational power as quantum circuits with unbounded fan-out. It demonstrates that the one-way model is not only one of the most promising models of physical realisation, but also a…

Quantum Physics · Physics 2010-08-12 Dan E. Browne , Elham Kashefi , Simon Perdrix

We consider the region of closed timelike curves (CTC's) in three-dimensional flat Lorentz spacetimes. The interest in this global geometrical feature goes beyond the purely mathematical. Such spacetimes may be considered lower-dimensional…

Differential Geometry · Mathematics 2009-11-07 Virginie Charette , Todd A. Drumm , Dieter Brill

We present a cyclic symmetric space-time, admitting closed time-like curves (CTCs) which appear after a certain instant of time, i. e., a time-machine space-time. These closed time-like curves evolve from an initial spacelike hypersurface…

General Relativity and Quantum Cosmology · Physics 2021-05-19 Faizuddin Ahmed

We discuss the concept of proper and improper density matrixes and we argue that this issue is of fundamental importance for the understanding of the quantum-mechanical CTC model proposed by Deutsch. We arrive at the conclusion that under a…

Quantum Physics · Physics 2012-03-14 A. C. Lobo , I. L. Paiva , P. R. Dieguez

One of the fundamental conditions for one-way quantum computation (1WQC) is the ability to make sequential measurements on isolated qubits that comprise the highly entangled resource for 1WQC, the cluster state. This has been a significant…

Quantum Physics · Physics 2009-11-13 Timothy P. Friesen , David L. Feder

We study the nature of entanglement in presence of Deutschian closed timelike curves (D-CTCs) and we observe that qubits traveling along a D-CTC allow unambiguous discrimination of Bell states with Local Operations and Classical…

Quantum Physics · Physics 2022-10-20 Subhayan Roy Moulick , Prasanta K. Panigrahi

Quantum measurement is universal for quantum computation. Two models for performing measurement-based quantum computation exist: the one-way quantum computer was introduced by Briegel and Raussendorf, and quantum computation via projective…

Quantum Physics · Physics 2008-12-08 Philippe Jorrand , Simon Perdrix

Measurement-based quantum computation (MBQC) represents a powerful and flexible framework for quantum information processing, based on the notion of entangled quantum states as computational resources. The most prominent application is the…

Quantum Physics · Physics 2014-05-26 B. P. Lanyon , P. Jurcevic , M. Zwerger , C. Hempel , E. A. Martinez , W. Dür , H. J. Briegel , R. Blatt , C. F. Roos

Measurement-based quantum computation is a framework of quantum computation, where entanglement is used as a resource and local measurements on qubits are used to drive the computation. It originates from the one-way quantum computer of…

Quantum Physics · Physics 2021-09-22 Tzu-Chieh Wei

It is known that a party with access to a Deutschian closed timelike curve (D-CTC) can perfectly distinguish multiple non-orthogonal quantum states. In this paper, we propose a practical method for discriminating multiple non-orthogonal…

Quantum Physics · Physics 2022-05-25 Christopher Vairogs , Vishal Katariya , Mark M. Wilde

In this paper we argue that one-way quantum computation can be seen as a form of phase transition with the available information about the solution of the computation being the order parameter. We draw a number of striking analogies between…

Quantum Physics · Physics 2009-11-13 Janet Anders , Damian Markham , Vlatko Vedral , Michal Hajdušek

We construct a metrology experiment in which the metrologist can sometimes amend her input state by simulating a closed timelike curve, a worldline that travels backward in time. The existence of closed timelike curves is hypothetical.…

Quantum Physics · Physics 2023-11-07 David R. M. Arvidsson-Shukur , Aidan G. McConnell , Nicole Yunger Halpern

We investigate the relationship between computation and spacetime structure, focussing on the role of closed timelike curves (CTCs) in promoting computational speedup. We note first that CTC traversal can be interpreted in two distinct…

General Relativity and Quantum Cosmology · Physics 2011-03-08 Mike Stannett

We examine mixedness and entanglement of the chronology-respecting (CR) system with assuming that quantum mechanical closed timelike curves (CTCs) exist in nature and by introducing the qubit system and applying the general controlled…

High Energy Physics - Theory · Physics 2016-07-04 Eylee Jung , DaeKil Park

This is the first in a series of papers aiming to develop a relativistic quantum information theory in terms of unequal-time correlation functions in quantum field theory. In this work, we highlight two formalisms which together can provide…

Quantum Physics · Physics 2023-02-15 Charis Anastopoulos , Bei-Lok Hu , Konstantina Savvidou

One-way quantum computing is experimentally appealing because it requires only local measurements on an entangled resource called a cluster state. Record-size, but non-universal, continuous-variable cluster states were recently demonstrated…

Einstein's field equations of gravitation are known to admit closed timelike curve (CTC) solutions. Deutsch approached the problem from the quantum information point of view and proposed a self-consistency condition. In this work, the…

Quantum Physics · Physics 2012-01-25 Z. Gedik

A one-way quantum computer works by only performing a sequence of one-qubit measurements on a particular entangled multi-qubit state, the cluster state. No non-local operations are required in the process of computation. Any quantum logic…

Quantum Physics · Physics 2023-11-11 Robert Raussendorf , Daniel E. Browne , Hans J. Briegel

In this paper we present the computational model underlying the one-way quantum computer which we introduced recently [Phys. Rev. Lett. 86, 5188 (2001)]. The one-way quantum computer has the property that any quantum logic network can be…

Quantum Physics · Physics 2007-05-23 Robert Raussendorf , Hans Briegel