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Related papers: On the Quantum Black-Box Complexity of Majority

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This paper initiates the study of quantum computing within the constraints of using a polylogarithmic ($O(\log^k n), k\geq 1$) number of qubits and a polylogarithmic number of computation steps. The current research in the literature has…

Quantum Physics · Physics 2007-05-23 Sanjay Gupta , R. K. P. Zia

In this article we give several new results on the complexity of algorithms that learn Boolean functions from quantum queries and quantum examples. Hunziker et al. conjectured that for any class C of Boolean functions, the number of quantum…

Quantum Physics · Physics 2007-05-23 Alp Atici , Rocco A. Servedio

Digital computers store information in the form of bits that can take on one of two values 0 and 1, while quantum computers are based on qubits that are described by a complex wavefunction, whose squared magnitude gives the probability of…

Emerging Technologies · Computer Science 2021-10-14 Jan Kaiser , Supriyo Datta

The current paper presents a new quantum algorithm for finding multicollisions, often denoted by $\ell$-collisions, where an $\ell$-collision for a function is a set of $\ell$ distinct inputs that are mapped by the function to the same…

Quantum Physics · Physics 2019-11-11 Akinori Hosoyamada , Yu Sasaki , Seiichiro Tani , Keita Xagawa

Parity (XOR) classification requires detecting discrete, high-order feature interactions that smooth classical kernels cannot efficiently capture. We study how quantum kernel advantage depends on parity complexity, the number of features…

Quantum Physics · Physics 2026-05-08 Tushar Pandey

Quantum error mitigation is an important technique to reduce the impact of noise in quantum computers. With more and more qubits being supported on quantum computers, there are two emerging fundamental challenges. First, the number of shots…

Quantum Physics · Physics 2025-01-14 Dror Baron , Hrushikesh Pramod Patil , Huiyang Zhou

Accurate uncertainty quantification is a critical challenge in machine learning. While neural networks are highly versatile and capable of learning complex patterns, they often lack interpretability due to their ``black box'' nature. On the…

Machine Learning · Computer Science 2025-11-18 Pragatheeswaran Vipulananthan , Kamal Premaratne , Dilip Sarkar , Manohar N. Murthi

We propose a new finding $k$-minima algorithm and prove that its query complexity is $\mathcal{O}(\sqrt{kN})$, where $N$ is the number of data indices. Though the complexity is equivalent to that of an existing method, the proposed is…

Quantum Physics · Physics 2019-07-09 Kohei Miyamoto , Masakazu Iwamura , Koichi Kise

In this paper, we will use a quantum operator which performs the inversion about the mean operation only on a subspace of the system ({\it Partial Diffusion Operator}) to propose a quantum search algorithm runs in $O(\sqrt N/M})$ for…

Quantum Physics · Physics 2009-11-10 Ahmed Younes , Jon Rowe , Julian Miller

It has been known for almost three decades that many $\mathrm{NP}$-hard optimization problems can be solved in polynomial time when restricted to structures of constant treewidth. In this work we provide the first extension of such results…

Computational Complexity · Computer Science 2016-02-09 Mateus de Oliveira Oliveira

The Quantum Approximate Optimization Algorithm can be applied to search problems on graphs with a cost function that is a sum of terms corresponding to the edges. When conjugating an edge term, the QAOA unitary at depth p produces an…

Quantum Physics · Physics 2020-05-19 Edward Farhi , David Gamarnik , Sam Gutmann

In this paper, we consider the partial database search problem where given a database on N items, we are required to determine the first k bits of an address x such that f(x)=1. We derive an algorithm and a lower bound for this problem in…

Quantum Physics · Physics 2007-05-23 Lov K. Grover , Jaikumar Radhakrishnan

Coin-flipping is a cryptographic task in which two physically separated, mistrustful parties wish to generate a fair coin-flip by communicating with each other. Chailloux and Kerenidis (2009) designed quantum protocols that guarantee…

Optimization and Control · Mathematics 2018-03-22 Ashwin Nayak , Jamie Sikora , Levent Tunçel

This paper describes a quantum algorithm for finding the maximum among N items. The classical method for the same problem takes O(N) steps because we need to compare two numbers in one step. This algorithm takes O(sqrt(N)) steps by…

Quantum Physics · Physics 2007-05-23 Ashish Ahuja , Sanjiv Kapoor

In an ordinary quantum algorithm the gates are applied in a fixed order on the systems. The introduction of indefinite causal structures allows to relax this constraint and control the order of the gates with an additional quantum state. It…

Quantum Physics · Physics 2022-06-15 Martin J. Renner , Časlav Brukner

We are presented with a graph, $G$, on $n$ vertices with $m$ edges whose edge set is unknown. Our goal is to learn the edges of $G$ with as few queries to an oracle as possible. When we submit a set $S$ of vertices to the oracle, it tells…

Quantum Physics · Physics 2024-03-01 Asaf Ferber , Liam Hardiman

We study the unsorted database search problem with items $N$ from the viewpoint of unitary discrimination. Instead of considering the famous $O(\sqrt{N})$ Grover's the bounded-error algorithm for the original problem, we seek for the…

Quantum Physics · Physics 2009-11-13 Xiaodi Wu , Runyao Duan

We consider online algorithms for the $k$-server problem on trees. Chrobak and Larmore proposed a $k$-competitive algorithm for this problem that has the optimal competitive ratio. However, a naive implementation of their algorithm has…

Data Structures and Algorithms · Computer Science 2021-07-29 Ruslan Kapralov , Kamil Khadiev , Joshua Mokut , Yixin Shen , Maxim Yagafarov

Quantum error-correcting codes protect fragile quantum information by encoding it redundantly, but identifying codes that perform well in practice with minimal overhead remains difficult due to the combinatorial search space and the high…

Quantum Physics · Physics 2026-01-27 Yihua Chengyu , Richard Meister , Conor Carty , Sheng-Ku Lin , Roberto Bondesan

We present several families of total boolean functions which have exact quantum query complexity which is a constant multiple (between 1/2 and 2/3) of their classical query complexity, and show that optimal quantum algorithms for these…

Quantum Physics · Physics 2016-02-24 Ashley Montanaro , Richard Jozsa , Graeme Mitchison