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Embeddings of graphs into distributions of trees that preserve distances in expectation are a cornerstone of many optimization algorithms. Unfortunately, online or dynamic algorithms which use these embeddings seem inherently randomized and…

Data Structures and Algorithms · Computer Science 2021-02-11 Bernhard Haeupler , D Ellis Hershkowitz , Goran Zuzic

CLIFFORD performs various computations in Grassmann and Clifford algebras. It can compute with quaternions, octonions, and matrices with entries in Cl(B) - the Clifford algebra of a vector space V endowed with an arbitrary bilinear form B.…

Mathematical Physics · Physics 2013-01-14 Rafal Ablamowicz , Bertfried Fauser

In this paper, we consider tree decompositions, branch decompositions, and clique decompositions. We improve the running time of dynamic programming algorithms on these graph decompositions for a large number of problems as a function of…

Data Structures and Algorithms · Computer Science 2018-06-06 Johan M. M. van Rooij , Hans L. Bodlaender , Erik Jan van Leeuwen , Peter Rossmanith , Martin Vatshelle

In this paper, we study quantum algorithms for computing the exact value of the treewidth of a graph. Our algorithms are based on the classical algorithm by Fomin and Villanger (Combinatorica 32, 2012) that uses $O(2.616^n)$ time and…

Quantum Physics · Physics 2022-02-17 Vladislavs Kļevickis , Krišjānis Prūsis , Jevgēnijs Vihrovs

The \emph{Steiner tree} problem is one of the fundamental and classical problems in combinatorial optimization. In this paper, we study this problem in the $\mathcal{CONGESTED}$ $\mathcal{CLIQUE}$ model of distributed computing and present…

Distributed, Parallel, and Cluster Computing · Computer Science 2019-07-31 Parikshit Saikia , Sushanta Karmakar

The Cut & Count technique and the rank-based approach have lead to single-exponential FPT algorithms parameterized by treewidth, that is, running in time $2^{O(tw)}n^{O(1)}$, for Feedback Vertex Set and connected versions of the classical…

Data Structures and Algorithms · Computer Science 2020-07-29 Benjamin Bergougnoux , Édouard Bonnet , Nick Brettell , O-joung Kwon

Some connections between quadratic forms over the field of two elements, Clifford algebras of quadratic forms over the real numbers, real graded division algebras, and twisted group algebras will be highlighted. This allows to revisit real…

Rings and Algebras · Mathematics 2020-02-28 Alberto Elduque , Adrián Rodrigo-Escudero

A large number of NP-hard graph problems can be solved in $f(w)n^{O(1)}$ time and space when the input graph is provided together with a tree decomposition of width $w$, in many cases with a modest exponential dependence $f(w)$ on $w$.…

Data Structures and Algorithms · Computer Science 2026-03-26 Stefan Kratsch

We revisit the classical problem of computing the \emph{contour tree} of a scalar field $f:\mathbb{M} \to \mathbb{R}$, where $\mathbb{M}$ is a triangulated simplicial mesh in $\mathbb{R}^d$. The contour tree is a fundamental topological…

Computational Geometry · Computer Science 2015-12-11 Benjamin Raichel , C. Seshadhri

In this paper is shown an application of Clifford algebras to the construction of computationally universal sets of quantum gates for $n$-qubit systems. It is based on the well-known application of Lie algebras together with the especially…

Quantum Physics · Physics 2009-11-06 Alexander Yu. Vlasov

Recently author suggested [quant-ph/0010071] an application of Clifford algebras for construction of a "compiler" for universal binary quantum computer together with later development [quant-ph/0012009] of the similar idea for a non-binary…

Quantum Physics · Physics 2007-05-23 Alexander Yu. Vlasov

Graph polynomials encode fundamental combinatorial invariants of graphs. Their computation is investigated using tree and path decomposition frameworks, with formal definitions of treewidth, k-trees, and pathwidth establishing the…

Discrete Mathematics · Computer Science 2025-09-29 Mehul Bafna , Shaghik Amirian

Within the growing interest in the physical sciences in developing networks with equivariance properties, Clifford neural layers shine as one approach that delivers $E(n)$ and $O(n)$ equivariances given specific group actions. In this…

Machine Learning · Computer Science 2025-10-07 X. Angelo Huang , Ruben Ciranni , Giovanni Spadaccini , Carla J. López Zurita

In this paper we further develop the method of quaternion typification of Clifford algebra elements suggested by the author in the previous paper. On the basis of new classification of Clifford algebra elements it is possible to reveal and…

Mathematical Physics · Physics 2017-08-22 Dmitry Shirokov

The Path Contraction and Cycle Contraction problems take as input an undirected graph $G$ with $n$ vertices, $m$ edges and an integer $k$ and determine whether one can obtain a path or a cycle, respectively, by performing at most $k$ edge…

Data Structures and Algorithms · Computer Science 2024-03-12 R. Krithika , V. K. Kutty Malu , Prafullkumar Tale

We suggest Clifford algebra as a useful simplifying language for present quantum dynamics. Clifford algebras arise from representations of the permutation groups as they arise from representations of the rotation groups. Aggregates using…

High Energy Physics - Theory · Physics 2009-10-31 James Baugh , David Ritz Finkelstein , Andrei Galiautdinov , Heinrich Saller

We study connectivity problems from a fine-grained parameterized perspective. Cygan et al. (TALG 2022) obtained algorithms with single-exponential running time $\alpha^{tw} n^{O(1)}$ for connectivity problems parameterized by treewidth…

Data Structures and Algorithms · Computer Science 2023-03-01 Falko Hegerfeld , Stefan Kratsch

The cost-distance Steiner tree problem seeks a Steiner tree that minimizes the total congestion cost plus the weighted sum of source-sink delays. This problem arises as a subroutine in timing-constrained global routing with a linear delay…

Data Structures and Algorithms · Computer Science 2025-03-07 Stephan Held , Edgar Perner

We give an algorithm which produces a unique element of the Clifford group $\mathcal{C}_n$ on $n$ qubits from an integer $0\le i < |\mathcal{C}_n|$ (the number of elements in the group). The algorithm involves $O(n^3)$ operations. It is a…

Quantum Physics · Physics 2022-12-11 Robert Koenig , John A. Smolin

In this work we explore the structure of Clifford algebras and the representations of the algebraic spinors in quantum information theory. Initially we present an general formulation through elements of left minimal ideals in tensor…

Mathematical Physics · Physics 2021-02-03 Marco A. S. Trindade , Sergio Floquet , J. D. M. Vianna