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Related papers: Quantum parallelism may be limited

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While quantum architectures are still under development, when available, they will only be able to process quantum data when machine learning algorithms can only process numerical data. Therefore, in the issues of classification or…

Machine Learning · Computer Science 2025-12-16 Rafal Potempa , Sebastian Porebski

In this addendum of our paper [D. Burgarth and V. Giovannetti, Phys. Rev. Lett. 99, 100501 (2007)] we prove that during the transformation that allows one to enforce control by relaxation on a quantum system, the ancillary memory can be…

Quantum Physics · Physics 2010-09-08 Daniel Burgarth , Vittorio Giovannetti

Demonstrating quantum advantage has been a pressing challenge in the field. Most claimed quantum speedups rely on a subroutine in which classical information can be accessed in a coherent quantum manner, which imposes a crucial constraint…

Quantum Physics · Physics 2025-11-04 Nhat A. Nghiem

This paper is devoted to such a fundamental problem of quantum computing as quantum parallelism. It is well known that quantum parallelism is the basis of the ability of quantum computer to perform in polynomial time computations performed…

Quantum Physics · Physics 2008-03-11 Andrei Khrennikov

Quantum theory (QT) has been confirmed by numerous experiments, yet we still cannot fully grasp the meaning of the theory. As a consequence, the quantum world appears to us paradoxical. Here we shed new light on QT by having it follow from…

Quantum Physics · Physics 2019-02-12 Alessio Benavoli , Alessandro Facchini , Marco Zaffalon

The model of open quantum systems is adopted to describe the non-local dynamical behaviour of qubits processed by entangling gates. The analysis gets to the conclusion that a distinction between evaluation steps and task-oriented computing…

Quantum Physics · Physics 2015-12-24 Stefano Bonzio , Paola Verrucchi

Quantum algorithms can deliver asymptotic speedups over their classical counterparts. However, there are few cases where a substantial quantum speedup has been worked out in detail for reasonably-sized problems, when compared with the best…

Quantum Physics · Physics 2019-07-24 Earl Campbell , Ankur Khurana , Ashley Montanaro

The quantum world is fascinating. It presents a description of nature that defies our most rooted concepts about what reality is. For example, quantum objects possess \lq\lq spooky\rq\rq\ properties that allow them to be in multiple places…

Mesoscale and Nanoscale Physics · Physics 2018-01-23 M. Fernando Gonzalez-Zalba

Quantum computers hold promise to improve the efficiency of quantum simulations of materials and to enable the investigation of systems and properties more complex than tractable at present on classical architectures. Here, we discuss…

Quantum Physics · Physics 2022-05-03 Christian Vorwerk , Nan Sheng , Marco Govoni , Benchen Huang , Giulia Galli

In classical computation, a "write-only memory" (WOM) is little more than an oxymoron, and the addition of WOM to a (deterministic or probabilistic) classical computer brings no advantage. We prove that quantum computers that are augmented…

Computational Complexity · Computer Science 2014-01-29 Abuzer Yakaryilmaz , Rusins Freivalds , A. C. Cem Say , Ruben Agadzanyan

In the last few years, theoretical study of quantum systems serving as computational devices has achieved tremendous progress. We now have strong theoretical evidence that quantum computers, if built, might be used as a dramatically…

Quantum Physics · Physics 2016-11-03 Dorit Aharonov

Quantum computers are the promising candidates for simulation of large quantum systems, which is a daunting task to perform in a classical computer. Here, we report the experimental realization of quantum tunneling of a single particle…

Precise rules are developed in order to formalize the reasoning processes involved in standard non-relativistic quantum mechanics, with the help of analogies from classical physics. A classical or quantum description of a mechanical system…

Quantum Physics · Physics 2007-05-23 Robert B. Griffiths

Quantum computing promises exponential speed-ups for important simulation and optimization problems. It also poses new CAD problems that are similar to, but more challenging, than the related problems in classical (non-quantum) CAD, such as…

Quantum Physics · Physics 2011-11-04 George F. Viamontes , Igor L. Markov , John P. Hayes

Quantum simulations consist in the intentional reproduction of physical or unphysical models into another more controllable quantum system. Beyond establishing communication vessels between unconnected fields, they promise to solve complex…

Quantum Physics · Physics 2018-04-24 Lucas Lamata , Adrian Parra-Rodriguez , Mikel Sanz , Enrique Solano

Universal quantum computers are the only general purpose quantum computers known that can be implemented as of today. These computers consist of a classical memory component which controls the quantum memory. In this paper, the space…

Quantum Physics · Physics 2020-11-03 Yanglin Hu , Darya Melnyk , Yuyi Wang , Roger Wattenhofer

As simulations of quantum systems cross the limits of classical computability, both quantum and classical approaches become hard to verify. Scaling predictions are therefore based on local structure and asymptotic assumptions, typically…

Quantum Physics · Physics 2025-08-22 Alberto Nocera , Jack Raymond , William Bernoudy , Mohammad H. Amin , Andrew D. King

Insofar as quantum computation is faster than classical, it appears to be irreversible. In all quantum algorithms found so far the speed-up depends on the extra-dynamical irreversible projection representing quantum measurement. Quantum…

Quantum Physics · Physics 2009-11-06 Giuseppe Castagnoli , David Ritz Finkelstein

Digital quantum computers promise exponential speedups in performing quantum time-evolution, providing an opportunity to simulate quantum dynamics of complex systems in physics and chemistry. However, the task of extracting desired quantum…

Quantum Physics · Physics 2025-03-10 Chong Hian Chee , Daniel Leykam , Adrian M. Mak , Kishor Bharti , Dimitris G. Angelakis

Quantum devices can process data in a fundamentally different way than classical computers. To leverage this potential, many algorithms require the aid of a quantum Random Access Memory (QRAM), i.e. a module capable of efficiently loading…

Quantum Physics · Physics 2025-03-26 Francesco Cesa , Hannes Bernien , Hannes Pichler