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A previously developed quantum search algorithm for solving 1-SAT problems in a single step is generalized to apply to a range of highly constrained k-SAT problems. We identify a bound on the number of clauses in satisfiability problems for…

Artificial Intelligence · Computer Science 2011-05-30 T. Hogg

We present an idealized quantum continuous variable analog of the Deutsch-Jozsa algorithm which can be implemented on a perfect continuous variable quantum computer. Using the Fourier transformation and XOR gate appropriate for continuous…

Quantum Physics · Physics 2007-05-23 Arun K. Pati , Samuel L. Braunstein

Ordinary approach to quantum algorithm is based on quantum Turing machine or quantum circuits. It is known that this approach is not powerful enough to solve NP-complete problems. In this paper we study a new approach to quantum algorithm…

Quantum Physics · Physics 2015-06-26 Masanori Ohya , Igor V. Volovich

We show that quantum oracles provide an advantage over classical oracles for answering classical counterfactual questions in causal models, or equivalently, for identifying unknown causal parameters such as distributions over functional…

Quantum Physics · Physics 2025-12-16 Ciarán M. Gilligan-Lee , Yìlè Yīng , Jonathan Richens , David Schmid

This work revisits quantum algorithms for the well-known welded tree problem, proposing a very succinct quantum algorithm based on the simplest coined quantum walks. It simply iterates the naturally defined coined quantum walk operator for…

Quantum Physics · Physics 2023-10-24 Guanzhong Li , Lvzhou Li , Jingquan Luo

Indefinite causal order has found numerous applications in quantum computation, quantum communication, and quantum metrology. Before its usage, the quality of the indefinite causal order needs to be first certified, and the certification…

Quantum Physics · Physics 2023-07-26 Zhu Cao

We propose an implementation of a quantum computer to solve Deutsch's problem, which requires exponential time on a classical computer but only linear time with quantum parallelism. By using a dual-rail qubit representation as a simple form…

Quantum Physics · Physics 2009-10-28 I. L. Chuang , Y. Yamamoto

Many quantum algorithms can be represented in a form of a classical circuit positioned between quantum Fourier transformations. Motivated by the search for new quantum algorithms, we turn to circuits where the latter transformation is…

Quantum Physics · Physics 2019-07-03 Vojtěch Havlíček , Sergii Strelchuk , Kristan Temme

Indefinite causal orders have been shown to enable a precision of inverse square N in quantum parameter estimation, where N is the number of independent processes probed in an experiment. This surpasses the widely accepted ultimate quantum…

Quantum Physics · Physics 2025-05-07 Yu Guo , Yuehan Chen , Geng Chen , Xiao-Min Hu , Yun-Feng Huang , Chuan-Feng Li , Guang-Can Guo , Bi-Heng Liu

Quantum computers can efficiently solve problems which are widely believed to lie beyond the reach of classical computers. In the near-term, hybrid quantum-classical algorithms, which efficiently embed quantum hardware in classical…

Quantum Physics · Physics 2026-05-07 Ananda Roy , Robert M. Konik , David Rogerson

The Deustch-Jozsa problem is one of the most basic ways to demonstrate the power of quantum computation. Consider a Boolean function f : {0,1}^n to {0,1} and suppose we have a black-box to compute f. The Deutsch-Jozsa problem is to…

Quantum Physics · Physics 2022-01-05 Alastair A. Abbott

We present an original model of paraconsistent Turing machines (PTMs), a generalization of the classical Turing machines model of computation using a paraconsistent logic. Next, we briefl y describe the standard models of quantum…

Quantum Physics · Physics 2007-05-23 Juan C. Agudelo , Walter Carnielli

We investigate the power of quantum computers when they are required to return an answer that is guaranteed to be correct after a time that is upper-bounded by a polynomial in the worst case. We show that a natural generalization of Simon's…

Quantum Physics · Physics 2017-01-04 Gilles Brassard , Peter Hoyer

Simulating nonlinear classical dynamics on a quantum computer is an inherently challenging task due to the linear operator formulation of quantum mechanics. In this work, we provide a systematic approach to alleviate this difficulty by…

Attempts to find new quantum algorithms that outperform classical computation have focused primarily on the nonabelian hidden subgroup problem, which generalizes the central problem solved by Shor's factoring algorithm. We suggest an…

Quantum Physics · Physics 2008-07-10 Andrew M. Childs , Leonard J. Schulman , Umesh V. Vazirani

An astonishing feature of higher-order quantum theory is that it can accommodate indefinite causal order. In the simplest bipartite setting, there exist signaling correlations for which it is fundamentally impossible to ascribe a definite…

Quantum Physics · Physics 2024-11-05 Jessica Bavaresco , Ämin Baumeler , Yelena Guryanova , Costantino Budroni

Deutsch's algorithm is the simplest quantum algorithm which shows the acceleration of quantum computer. In this paper, we theoretically advance a scheme to implement quantum Deutsch's algorithm in spin-orbital angular momentum space. Our…

Quantum Physics · Physics 2012-07-25 Pei Zhang , Yan Jiang , Rui-Feng Liu , Hong Gao , Hong-Rong Li , Fu-Li Li

Entanglement is widely believed to lie at the heart of the advantages offered by a quantum computer. This belief is supported by the discovery that a noiseless (pure) state quantum computer must generate a large amount of entanglement in…

Quantum Physics · Physics 2008-11-16 B. P. Lanyon , M. Barbieri , M. P. Almeida , A. G. White

Many interesting computational problems can be reformulated in terms of decision trees. A natural classical algorithm is to then run a random walk on the tree, starting at the root, to see if the tree contains a node n levels from the root.…

Quantum Physics · Physics 2009-10-30 Edward Farhi , Sam Gutmann

Quantum algorithms are typically understood in terms of the evolution of a multi-qubit quantum system under a prescribed sequence of unitary transformations. The input to the algorithm prescribes some of the unitary transformations in the…

Quantum Physics · Physics 2015-05-13 David Collins