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The hidden shift problem is a natural place to look for new separations between classical and quantum models of computation. One advantage of this problem is its flexibility, since it can be defined for a whole range of functions and a…

Quantum Physics · Physics 2013-12-05 Dmitry Gavinsky , Martin Roetteler , Jérémie Roland

A quantum computer directly manipulates information stored in the state of quantum mechanical systems. The available operations have many attractive features but also underly severe restrictions, which complicate the design of quantum…

Quantum Physics · Physics 2015-06-26 Sos S. Agaian , Andreas Klappenecker

We introduce a novel quantum programming language featuring higher-order programs and quantum controlflow which ensures that all qubit transformations are unitary. Our language boasts a type system guaranteeingboth unitarity and…

Logic in Computer Science · Computer Science 2024-03-06 Alejandro Díaz-Caro , Emmanuel Hainry , Romain Péchoux , Mário Silva

We investigate quantum algorithms for classification, a fundamental problem in machine learning, with provable guarantees. Given $n$ $d$-dimensional data points, the state-of-the-art (and optimal) classical algorithm for training…

Quantum Physics · Physics 2019-05-28 Tongyang Li , Shouvanik Chakrabarti , Xiaodi Wu

We initiate the study of parallel quantum programming by defining the operational and denotational semantics of parallel quantum programs. The technical contributions of this paper include: (1) find a series of useful proof rules for…

Logic in Computer Science · Computer Science 2019-10-02 Mingsheng Ying , Li Zhou , Yangjia Li

Implementing quantum algorithms on realistic hardware requires translating high-level global operations into sequences of native elementary gates, a process known as quantum compiling. Physical limitations, such as constraints in…

We present an algorithm for approximating semidefinite programs with running time that is sublinear in the number of entries in the semidefinite instance. We also present lower bounds that show our algorithm to have a nearly optimal running…

Optimization and Control · Mathematics 2012-08-28 Dan Garber , Elad Hazan

The subject of this paper is the time complexity of approximating Knapsack, Subset Sum, Partition, and some other related problems. The main result is an $\widetilde{O}(n+1/\varepsilon^{5/3})$ time randomized FPTAS for Partition, which is…

Data Structures and Algorithms · Computer Science 2019-05-07 Marcin Mucha , Karol Węgrzycki , Michał Włodarczyk

Owing to the computational complexity of electronic structure algorithms running on classical digital computers, the range of molecular systems amenable to simulation remains tightly circumscribed even after many decades of work. Quantum…

Quantum Physics · Physics 2022-05-18 Alexis Ralli , Michael I. Williams , Peter V. Coveney

Quantum algorithms require accurate representations of electronic states on a quantum device, yet the approximation of electronic wave functions for strongly correlated systems remains a profound theoretical challenge, with existing methods…

Quantum Physics · Physics 2025-04-29 Dipanjali Halder , Dibyendu Mondal , Rahul Maitra

Quantum algorithms require a universal set of gates that can be implemented in a physical system. For these, an optimal decomposition into a sequence of available operations is desired. Here, we present a method to find such sequences for a…

Quantum Physics · Physics 2016-07-22 Esteban A. Martinez , Thomas Monz , Daniel Nigg , Philipp Schindler , Rainer Blatt

Combinatorial optimization problems are considered to be an application, where quantum computing can have transformative impact. In the industrial context, job shop scheduling problems that aim at finding the optimal schedule for a set of…

Quantum Physics · Physics 2025-02-12 Mathias Schmid , Sarah Braun , Rudolf Sollacher , Michael J. Hartmann

A prominent problem in scheduling theory is the weighted flow time problem on one machine. We are given a machine and a set of jobs, each of them characterized by a processing time, a release time, and a weight. The goal is to find a…

Data Structures and Algorithms · Computer Science 2023-08-14 Alexander Armbruster , Lars Rohwedder , Andreas Wiese

We address the problem of analysing the complexity of concurrent programs written in Pi-calculus. We are interested in parallel complexity, or span, understood as the execution time in a model with maximal parallelism. A type system for…

Computational Complexity · Computer Science 2021-10-20 Patrick Baillot , Alexis Ghyselen , Naoki Kobayashi

Recently, there has been a surge of interest for quantum computation for its ability to exponentially speed up algorithms, including machine learning algorithms. However, Tang suggested that the exponential speed up can also be done on a…

Discrete Mathematics · Computer Science 2020-12-03 Daniel Chen , Yekun Xu , Betis Baheri , Samuel A. Stein , Chuan Bi , Ying Mao , Qiang Quan , Shuai Xu

Quadratic programming is a ubiquitous prototype in convex programming. Many machine learning problems can be formulated as quadratic programming, including the famous Support Vector Machines (SVMs). Linear and kernel SVMs have been among…

Optimization and Control · Mathematics 2025-02-13 Yuzhou Gu , Zhao Song , Lichen Zhang

As quantum computing technology advances, the complexity of quantum algorithms increases, necessitating a shift from low-level circuit descriptions to high-level programming paradigms. This paper addresses the challenges of developing a…

Quantum Physics · Physics 2025-03-04 Israel Reichental , Ravid Alon , Lior Preminger , Matan Vax , Amir Naveh

Gaussian Process Regression is a well-known machine learning technique for which several quantum algorithms have been proposed. We show here that in a wide range of scenarios these algorithms show no exponential speedup. We achieve this by…

Quantum Physics · Physics 2025-07-04 Dominic Lowe , M. S. Kim , Roberto Bondesan

We consider the problem of solving integer programs of the form $\min \{\,c^\intercal x\ \colon\ Ax=b, x\geq 0\}$, where $A$ is a multistage stochastic matrix in the following sense: the primal treedepth of $A$ is bounded by a parameter…

Data Structures and Algorithms · Computer Science 2020-12-23 Jana Cslovjecsek , Friedrich Eisenbrand , Michał Pilipczuk , Moritz Venzin , Robert Weismantel

Feynman's circuit-to-Hamiltonian construction enables the mapping of a quantum circuit to a time-independent Hamiltonian. This model introduces a Hilbert space made from an ancillary clock register tracking the progress of the computation.…

Quantum Physics · Physics 2025-01-23 Ralph Jason Costales , Alex Gunning , Tony Dorlas