English
Related papers

Related papers: Short paths in PU(2)

200 papers

The problem of decomposing an arbitrary Clifford element into a sequence of Clifford gates is known as Clifford synthesis. Drawing inspiration from similarities between this and the famous Rubik's Cube problem, we develop a machine learning…

Quantum Physics · Physics 2024-03-12 Ning Bao , Gavin S. Hartnett

We consider approximations for computing minimum weighted cuts in directed graphs. We consider both rooted and global minimum cuts, and both edge-cuts and vertex-cuts. For these problems we give randomized Monte Carlo algorithms that…

Data Structures and Algorithms · Computer Science 2021-04-15 Kent Quanrud

In this paper, we propose new techniques for solving geometric optimization problems involving interpoint distances of a point set in the plane. Given a set $P$ of $n$ points in the plane and an integer $1 \leq k \leq \binom{n}{2}$, the…

Computational Geometry · Computer Science 2024-03-08 Haitao Wang , Yiming Zhao

By the Gottesman-Knill Theorem, the outcome probabilities of Clifford circuits can be computed efficiently. We present an alternative proof of this result for quopit Clifford circuits (i.e., Clifford circuits on collections of $p$-level…

Quantum Physics · Physics 2021-04-13 Dax Enshan Koh , Mark D. Penney , Robert W. Spekkens

We introduce a new heuristic for the A* algorithm that references a data structure significantly smaller than that of ALT. We characterize the behavior of this new heuristic based on a dual landmark configuration that leverages…

Data Structures and Algorithms · Computer Science 2016-03-04 Newton Campbell

The Clifford group is a finite subgroup of the unitary group generated by the Hadamard, the CNOT, and the Phase gates. This group plays a prominent role in quantum error correction, randomized benchmarking protocols, and the study of…

Quantum Physics · Physics 2021-11-17 Sergey Bravyi , Ruslan Shaydulin , Shaohan Hu , Dmitri Maslov

Using Chebyshev polynomialsof both kinds, we construct rational fractions which are convergents of the smallest root of $x^2-\alpha x+1$ for $\alpha=3,4,5,\dots$.Some of the underlying identities suggest an identity involving…

Combinatorics · Mathematics 2015-10-01 Roland Bacher

We construct uniquely satisfiable $k$-CNF formulas that are hard for the algorithm PPSZ. Firstly, we construct graph-instances on which "weak PPSZ" has savings of at most $(2 + \epsilon) / k$; the saving of an algorithm on an input formula…

Computational Complexity · Computer Science 2017-09-06 Pavel Pudlák , Dominik Scheder , Navid Talebanfard

We investigate the fine-grained complexity of approximating the classical $k$-median / $k$-means clustering problems in general metric spaces. We show how to improve the approximation factors to $(1+2/e+\varepsilon)$ and…

Data Structures and Algorithms · Computer Science 2019-04-30 Vincent Cohen-Addad , Anupam Gupta , Amit Kumar , Euiwoong Lee , Jason Li

Graphs with bounded highway dimension were introduced by Abraham et al. [SODA 2010] as a model of transportation networks. We show that any such graph can be embedded into a distribution over bounded treewidth graphs with arbitrarily small…

Data Structures and Algorithms · Computer Science 2019-06-20 Andreas Emil Feldmann , Wai Shing Fung , Jochen Könemann , Ian Post

The (non-uniform) sparsest cut problem is the following graph-partitioning problem: given a "supply" graph, and demands on pairs of vertices, delete some subset of supply edges to minimize the ratio of the supply edges cut to the total…

Data Structures and Algorithms · Computer Science 2021-06-01 Vincent Cohen-Addad , Anupam Gupta , Philip N. Klein , Jason Li

We propose practical algorithms for entrywise $\ell_p$-norm low-rank approximation, for $p = 1$ or $p = \infty$. The proposed framework, which is non-convex and gradient-based, is easy to implement and typically attains better…

Machine Learning · Computer Science 2018-05-25 Anastasios Kyrillidis

Let $\mathcal{P}$ be a set of $h$ pairwise-disjoint polygonal obstacles with a total of $n$ vertices in the plane. We consider the problem of building a data structure that can quickly compute an $L_1$ shortest obstacle-avoiding path…

Computational Geometry · Computer Science 2014-03-17 Danny Z. Chen , Rajasekhar Inkulu , Haitao Wang

Many quantum information protocols require the implementation of random unitaries. Because it takes exponential resources to produce Haar-random unitaries drawn from the full $n$-qubit group, one often resorts to $t$-designs. Unitary…

We describe a new method for the decomposition of an arbitrary $n$ qubit operator with entries in $\mathbb{Z}[i,\frac{1}{\sqrt{2}}]$, i.e., of the form $(a+b\sqrt{2}+i(c+d\sqrt{2}))/{\sqrt{2}^{k}}$, into Clifford+$T$ operators where $n\le…

Quantum Physics · Physics 2014-08-27 Travis Russell

We present fast algorithms for approximate shortest paths in the massively parallel computation (MPC) model. We provide randomized algorithms that take $poly(\log{\log{n}})$ rounds in the near-linear memory MPC model. Our results are for…

Data Structures and Algorithms · Computer Science 2025-05-20 Michal Dory , Shaked Matar

Computing shortest paths is one of the most fundamental algorithmic graph problems. It is known since decades that this problem can be solved in near-linear time if all weights are nonnegative. A recent break-through by [Bernstein,…

Data Structures and Algorithms · Computer Science 2025-02-18 Alejandro Cassis , Andreas Karrenbauer , André Nusser , Paolo Luigi Rinaldi

Transversal gates play a crucial role in suppressing error propagation in fault-tolerant quantum computation, yet they are intrinsically constrained: any nontrivial code encoding a single logical qubit admits only a finite subgroup of…

Quantum Physics · Physics 2025-04-30 Chao Zhang , Zipeng Wu , Shilin Huang , Bei Zeng

We developed a general framework for synthesizing target gates by using a finite set of basic gates, which is a crucial step in quantum compilation. When approximating a gate in SU($n$), a naive brute-force search requires a computational…

Quantum Physics · Physics 2025-10-10 Soichiro Yamazaki , Seiseki Akibue

We present the first sub-quadratic time algorithm that with high probability correctly reconstructs phylogenetic trees for short sequences generated by a Markov model of evolution. Due to rapid expansion in sequence databases, such very…

Populations and Evolution · Quantitative Biology 2012-06-01 Daniel G. Brown , Jakub Truszkowski