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Related papers: Quantum Approximate Counting, Simplified

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Satisfiability (SAT) is a central problem in computer science, and advances in SAT-solving algorithms have a far-reaching impact across many fields. Recent works have proposed quantum SAT solvers based on Grover's algorithm, a quantum…

Quantum Physics · Physics 2026-04-21 Shang-Wei Lin , Ji-Qing Yan , Yean-Ru Chen , Zhe Hou , David Sanán

Quantum computers provide a super-exponential speedup for performing a Fourier transform over the symmetric group, an ability for which practical use cases have remained elusive so far. In this work, we leverage this ability to unlock…

Quantum Physics · Physics 2026-03-25 Vasilis Belis , Giulio Crognaletti , Matteo Argenton , Michele Grossi , Maria Schuld

In general, a quantum circuit is constructed with elementary gates, such as one-qubit gates and CNOT gates. It is possible, however, to speed up the execution time of a given circuit by merging those elementary gates together into larger…

Quantum Physics · Physics 2009-11-10 Mikio Nakahara , Yasushi Kondo , Kazuya Hata , Shogo Tanimura

We present fast and highly parallelized versions of Shor's algorithm. With a sizable quantum computer it would then be possible to factor numbers with millions of digits. The main algorithm presented here uses FFT-based fast integer…

Quantum Physics · Physics 2007-05-23 Christof Zalka

Quantum Fourier transform (QFT) is a key function to realize quantum computers. A QFT followed by measurement was demonstrated on a simple circuit based on fiber-optics. The QFT was shown to be robust against imperfections in the rotation…

Quantum Physics · Physics 2007-05-23 Akihisa Tomita , Kazuo Nakamura

Given an algorithm that outputs the correct answer with bounded error, say $1/3$, it is sometimes desirable to reduce this error to some arbitrarily small $\varepsilon$ -- e.g., if one wants to call the algorithm many times as a subroutine.…

Quantum Physics · Physics 2026-03-25 Aleksandrs Belovs , Stacey Jeffery

The Quantum Fourier Transform (QFT) is a key component of many important quantum algorithms, most famously as being the essential ingredient in Shor's algorithm for factoring products of primes. Given its remarkable capability, one would…

Quantum Physics · Physics 2023-10-31 Jielun Chen , E. M. Stoudenmire , Steven R. White

The remarkable capability of quantum Fourier transformation (QFT) to extract the periodicity of a given periodic function has been exhibited by using nuclear magnetic resonance (NMR) techniques. Two separate sets of experiments were…

Quantum Physics · Physics 2007-05-23 Xinhua Peng , Xiwen Zhu , Ximing Fang , Mang Feng , Xiaodong Yang , Maili Liu , Kelin Gao

We describe a simple quantum algorithm for preparing $K$ copies of an $N$-dimensional quantum state whose amplitudes are given by a quantum oracle. Our result extends a previous work of Grover, who showed how to prepare one copy in time…

Quantum Physics · Physics 2022-07-25 Yassine Hamoudi

We provide a tight analysis of Grover's recent algorithm for quantum database searching. We give a simple closed-form formula for the probability of success after any given number of iterations of the algorithm. This allows us to determine…

Quantum Physics · Physics 2015-06-26 Michel Boyer , Gilles Brassard , Peter Hoeyer , Alain Tapp

While Quantum phase estimation (QPE) is at the core of many quantum algorithms known to date, its physical implementation (algorithms based on quantum Fourier transform (QFT)) is highly constrained by the requirement of high-precision…

Quantum Physics · Physics 2013-06-12 Hamed Ahmadi , Chen-Fu Chiang

It has previously been established that the logarithmic-depth approximate quantum Fourier transform (AQFT) provides a suitable replacement for the regular QFT in many quantum algorithms. Since the AQFT is less accurate by definition,…

Quantum Physics · Physics 2007-05-23 Donny Cheung

The Quantum Fourier Transformation (QFT) is a well-known subroutine for algorithms on qubit-based universal quantum computers. In this work, the known QFT circuit is used to derive an efficient circuit for the multidimensional QFT. The…

Quantum Physics · Physics 2023-02-01 Philipp Pfeffer

Finding a Hadamard matrix of a specific order using a quantum computer can lead to a demonstration of practical quantum advantage. Earlier efforts using a quantum annealer were impeded by the limitations of the present quantum resource and…

Quantum Physics · Physics 2024-10-15 Andriyan Bayu Suksmono

We propose a quantum analogue of Bluestein's algorithm (QBA) that implements an exact $N$-point Quantum Fourier Transform (QFT) for arbitrary $N$. Our construction factors the $N$-dimensional QFT unitary into three diagonal quadratic-phase…

Quantum Physics · Physics 2025-12-24 Nan-Hong Kuo , Renata Wong

Detecting and counting copies of permutation patterns are fundamental algorithmic problems, with applications in the analysis of rankings, nonparametric statistics, and property testing tasks such as independence and quasirandomness…

Data Structures and Algorithms · Computer Science 2026-05-07 Michal Opler

$k$-Clustering in $\mathbb{R}^d$ (e.g., $k$-median and $k$-means) is a fundamental machine learning problem. While near-linear time approximation algorithms were known in the classical setting for a dataset with cardinality $n$, it remains…

Quantum Physics · Physics 2023-06-06 Yecheng Xue , Xiaoyu Chen , Tongyang Li , Shaofeng H. -C. Jiang

Quantum simulation is a cornerstone application for quantum computing, yet standard methods face a trade-off between circuit depth and accuracy: Trotterization depth scales with the number of Hamiltonian terms $L$, while sampling-based…

Quantum Physics · Physics 2026-05-01 Sangjin Lee , Sangkook Choi

Grover's quantum algorithm for an unstructured search problem and the Count algorithm by Brassard et al. are generalized to the case when the initial state is arbitrarily and maximally entangled. This ansatz might be relevant with quantum…

Quantum Physics · Physics 2007-05-23 A. Carlini , A. Hosoya

We generalize the binary quantum counting algorithm of Lesovik, Suslov, and Blatter [Phys. Rev. A 82, 012316 (2010)] to higher counting bases. The algorithm makes use of qubits, qutrits, and qudits to count numbers in a base 2, base 3, or…

Mesoscale and Nanoscale Physics · Physics 2013-05-29 M. V. Suslov , G. B. Lesovik , G. Blatter