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Related papers: Quantum Computing Spacetime

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Spacetime manifolds that are not time orientable play a key role in a gravitational explanation of quantum theory. Such manifolds allow topology change, but also have fascinating additional properties such as net charge from source-free…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Mark J Hadley

Quantum reservoir computing (QRC) is a hardware-implementation-friendly quantum neural network scheme with minimal physical system requirements and a proven advantage over classical counterparts. We use an extension of the positive-P phase…

Quantum Physics · Physics 2026-03-19 S. Świerczewski , W. Verstraelen , P. Deuar , T. C. H. Liew , A. Opala , M. Matuszewski

We introduce a model of computation based on quaternions, which is inspired on the quantum computing model. Pure states are vectors of a suitable linear space over the quaternions. Other aspects of the theory are the same as in quantum…

Quantum Physics · Physics 2007-05-23 Jose M. Fernandez , William A. Schneeberger

The standard formulation of quantum theory relies on a fixed space-time metric determining the localisation and causal order of events. In general relativity, the metric is influenced by matter, and is expected to become indefinite when…

Quantum Physics · Physics 2020-06-08 Esteban Castro-Ruiz , Flaminia Giacomini , Alessio Belenchia , Časlav Brukner

Quantum operations are the most widely used tool in the theory of quantum information processing, representing elementary transformations of quantum states that are composed to form complex quantum circuits. The class of quantum…

Quantum Physics · Physics 2018-07-25 Paolo Perinotti

Quantum cognition often explains order effects, contextuality, and violations of the law of total probability by replacing classical probability with quantum probability on a fixed event structure. This paper proposes a different…

Artificial Intelligence · Computer Science 2026-05-26 Song-Ju Kim

We describe the time evolution of quantum systems in a classical background space-time by means of a covariant derivative in an infinite dimensional vector bundle. The corresponding parallel transport operator along a timelike curve $\cC$…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Dirk Graudenz

Spacetime must be foliable by spacelike surfaces for the quantum mechanics of matter fields to be formulated in terms of a unitarily evolving state vector defined on spacelike surfaces. When a spacetime cannot be foliated by spacelike…

General Relativity and Quantum Cosmology · Physics 2009-10-22 James B. Hartle

Quantum computing exploits quantum phenomena such as superposition and entanglement to realize a form of parallelism that is not available to traditional computing. It offers the potential of significant computational speed-ups in quantum…

A quantum computer is a hypothetical device in which the laws of quantum mechanics are used to introduce a degree of parallelism into computations and which could therefore significantly improve on the computational speed of a classical…

Quantum Physics · Physics 2007-05-23 P. Blythe , B. Varcoe

We present an architecture of QCPU(Quantum Central Processing Unit), based on the discrete quantum gate set, that can be programmed to approximate any n-qubit computation in a deterministic fashion. It can be built efficiently to implement…

Quantum Physics · Physics 2009-11-07 Fei Xue , Zeng-Bing Chen , Mingjun Shi , Xianyi Zhou , Jiangfeng Du , Rongdian Han

The quantum computer is supposed to process information by applying unitary transformations to the complex amplitudes defining the state of N qubits. A useful machine needing N=1000 or more, the number of continuous parameters describing…

Quantum Physics · Physics 2014-09-23 M. I. Dyakonov

We propose the quantum mechanical description of complex systems should be performed using two types of causality relation: the ordering relation ($x\prec y$) and the subset relation ($A\subseteq B$). The structures with two ordering…

Quantum Physics · Physics 2016-07-26 M. V. Altaisky

In this paper is presented an abstract theory of quantum processors and controllers, special kind of quantum computational network defined on a composite quantum system with two parts: the controlling and controlled subsystems. Such…

Quantum Physics · Physics 2010-05-12 Alexander Yu. Vlasov

Treating the time of an event as a quantum variable, we derive a scheme in which superpositions in time are used to perform operations in an indefinite causal order. We use some aspects of a recently developed space-time-symmetric formalism…

Quantum Physics · Physics 2022-07-13 David Felce , Nicetu Tibau Vidal , Vlatko Vedral , Eduardo O. Dias

Research in quantum gravity strongly suggests that our world in not fundamentally spatiotemporal, but that spacetime may only emerge in some sense from a non-spatiotemporal structure, as this paper illustrates in the case of causal set…

History and Philosophy of Physics · Physics 2018-04-09 Christian Wuthrich

While the standard formulation of quantum theory assumes a fixed background causal structure, one can relax this assumption within the so-called process matrix framework. Remarkably, some processes, termed causally nonseparable, are…

Quantum Physics · Physics 2022-08-29 Hippolyte Dourdent , Alastair A. Abbott , Nicolas Brunner , Ivan Šupić , Cyril Branciard

We provide a model independent construction of a net of C*-algebras satisfying the Haag-Kastler axioms over any spacetime manifold. Such a net, called the net of causal loops, is constructed by selecting a suitable base K encoding causal…

Mathematical Physics · Physics 2021-11-04 Fabio Ciolli , Giuseppe Ruzzi , Ezio Vasselli

Quantum computers require quantum logic, something fundamentally different to classical Boolean logic. This difference leads to a greater efficiency of quantum computation over its classical counter-part. In this review we explain the basic…

Quantum Physics · Physics 2011-08-04 Vlatko Vedral , Martin B. Plenio

The quantum mechanical formalism doesn't support our intuition, nor does it elucidate the key concepts that govern the behaviour of the entities that are subject to the laws of quantum physics. The arrays of complex numbers are kin to the…

Quantum Physics · Physics 2015-05-13 Bob Coecke