English
Related papers

Related papers: Inverting a permutation is as hard as unordered se…

200 papers

Quantum span program algorithms for function evaluation sometimes have reduced query complexity when promised that the input has a certain structure. We design a modified span program algorithm to show these improvements persist even…

Quantum Physics · Physics 2024-04-10 Noel T. Anderson , Jay-U Chung , Shelby Kimmel , Da-Yeon Koh , Xiaohan Ye

We prove lower bounds on the error probability of a quantum algorithm for searching through an unordered list of N items, as a function of the number T of queries it makes. In particular, if T=O(sqrt{N}) then the error is lower bounded by a…

Quantum Physics · Physics 2007-05-23 Harry Buhrman , Ronald de Wolf

In this paper we continue to study so called ``inverse Born's rule problem'': to construct representation of probabilistic data of any origin by a complex probability amplitude which matches Born's rule. The corresponding algorithm --…

Mathematical Physics · Physics 2015-05-13 Peter Nyman

We present a simple $O(n^4)$-time algorithm for computing optimal search trees with two-way comparisons. The only previous solution to this problem, by Anderson et al., has the same running time, but is significantly more complicated and is…

Data Structures and Algorithms · Computer Science 2022-02-14 Marek Chrobak , Mordecai Golin , J. Ian Munro , Neal E. Young

In 1973, L.A. Levin published an algorithm that solves any inversion problem $\pi$ as quickly as the fastest algorithm $p^*$ computing a solution for $\pi$ in time bounded by $2^{l(p^*)}.t^*$, where $l(p^*)$ is the length of the binary…

Computational Complexity · Computer Science 2017-02-13 Fouad B. Chedid

Using evaluation at appropriately chosen points, we propose a Gr\"obner basis free approach for calculating the secondary invariants of a finite permutation group. This approach allows for exploiting the symmetries to confine the…

Combinatorics · Mathematics 2011-10-19 Nicolas Borie , Nicolas M. Thiéry

We introduce a structured quantum search algorithm that leverages entanglement maps and a fixed-point method to minimize oracle query complexity in unsorted datasets. By partitioning qubits into rows based on their entanglement order, the…

Quantum Physics · Physics 2025-07-22 Yash Prabhat , Snigdha Thakur , Ankur Raina

Recent efforts on solving inverse problems in imaging via deep neural networks use architectures inspired by a fixed number of iterations of an optimization method. The number of iterations is typically quite small due to difficulties in…

Image and Video Processing · Electrical Eng. & Systems 2021-06-04 Davis Gilton , Gregory Ongie , Rebecca Willett

We consider counterfactual explanations, the problem of minimally adjusting features in a source input instance so that it is classified as a target class under a given classifier. This has become a topic of recent interest as a way to…

Machine Learning · Computer Science 2021-03-02 Miguel Á. Carreira-Perpiñán , Suryabhan Singh Hada

The problem of demand inversion - a crucial step in the estimation of random utility discrete-choice models - is equivalent to the determination of stable outcomes in two-sided matching models. This equivalence applies to random utility…

Econometrics · Economics 2021-11-30 Odran Bonnet , Alfred Galichon , Yu-Wei Hsieh , Keith O'Hara , Matt Shum

It is always possible to decide, with one-sided error, whether two quantum states are the same under a specific unitary transformation. However we show here that it is {\em impossible} to do so if the transformation is anti-linear and…

Quantum Physics · Physics 2007-05-23 Chiu Fan Lee , Neil F. Johnson

We provide a simple approach for the evaluation of inverse integral transforms that does not require any knowledge of complex analysis. The central idea behind the method is to reduce the inverse transform to the solution of an ordinary…

Physics Education · Physics 2015-05-30 Aaron Farrell , Brandon P. van Zyl , Zachary MacDonald

Compression of inverted lists with methods that support fast intersection operations is an active research topic. Most compression schemes rely on encoding differences between consecutive positions with techniques that favor small numbers.…

Information Retrieval · Computer Science 2009-11-18 Francisco Claude , Antonio Farina , Gonzalo Navarro

We investigate a hybrid quantum-classical solution method to the mean-variance portfolio optimization problems. Starting from real financial data statistics and following the principles of the Modern Portfolio Theory, we generate…

Quantum Physics · Physics 2019-07-01 Davide Venturelli , Alexei Kondratyev

Inverted indexes allow to query large databases without needing to search in the database at each query. An important line of research is to construct the most efficient inverted indexes, both in terms of compression ratio and time…

Databases · Computer Science 2025-05-06 Yann Barsamian , André Chailloux

The notion of the Drazin inverse of an even-order tensor with the Einstein product was introduced, very recently [J. Ji and Y. Wei. Comput. Math. Appl., 75(9), (2018), pp. 3402-3413]. In this article, we further elaborate this theory by…

Numerical Analysis · Mathematics 2021-03-09 Ratikanta Behera , Ashish Kumar Nandi , Jajati Keshari Sahoo

In this paper we present an algorithm to find the discrete Lagrangian for an autonomous recurrence relation of arbitrary even order $2k$ with $k>1$. The method is based on the existence of a set of differential operators called annihilation…

Mathematical Physics · Physics 2019-10-28 G. Gubbiotti

We study the query complexity of quantum learning problems in which the oracles form a group $G$ of unitary matrices. In the simplest case, one wishes to identify the oracle, and we find a description of the optimal success probability of a…

Computational Complexity · Computer Science 2021-03-10 Daniel Copeland , Jamie Pommersheim

There are thousands of papers on rootfinding for nonlinear scalar equations. Here is one more, to talk about an apparently new method, which I call ``Inverse Cubic Iteration'' (ICI) in analogy to the Inverse Quadratic Iteration in Richard…

Numerical Analysis · Mathematics 2020-07-15 Robert M. Corless

In a remarkable development Bender and coworkers have shown that it is possible to formulate quantum mechanics consistently even if the Hamiltonian and other observables are not Hermitian. Their formulation, dubbed PT quantum mechanics,…

High Energy Physics - Theory · Physics 2010-11-02 Katherine Jones-Smith , Harsh Mathur