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Over the past decade, we witness an increasing amount of interest in the design of exact exponential-time and parameterized algorithms for problems in Graph Drawing. Unfortunately, we still lack knowledge of general methods to develop such…

Data Structures and Algorithms · Computer Science 2023-10-10 Siddharth Gupta , Guy Sa'ar , Meirav Zehavi

Algorithmic meta-theorems, stating that graph properties expressible in some particular logic can be decided efficiently in graph classes having some specific structural properties, are now standard in sequential graph algorithms. One of…

Data Structures and Algorithms · Computer Science 2025-07-16 Benjamin Jauregui , Jason Li , Pedro Montealegre , Ioan Todinca

We describe derivations of the Clifford algebra of a nondegenerate quadratic form on a countable dimensional vector space over an algebraically closed field of characteristic not equal to $2$. We also construct an algebraic automorphism of…

Rings and Algebras · Mathematics 2024-08-15 Oksana Bezushchak

This thesis discusses the young fields of quantum pseudo-randomness and quantum learning algorithms. We present techniques for derandomising algorithms to decrease randomness resource requirements and improve efficiency. One key object in…

Quantum Physics · Physics 2010-06-29 Richard A. Low

In this review, an overview is given of several recent generalizations of the Fourier transform, related to either the Lie algebra sl_2 or the Lie superalgebra osp(1|2). In the former case, one obtains scalar generalizations of the Fourier…

Mathematical Physics · Physics 2015-06-11 Hendrik De Bie

We propose to represent both $n$--qubits and quantum gates acting on them as elements in the complex Clifford algebra defined on a complex vector space of dimension $2n.$ In this framework, the Dirac formalism can be realized in…

Quantum Physics · Physics 2022-03-04 Jaroslav Hrdina , Ales Navrat , Petr Vasik

We consider network design problems with deadline or delay. All previous results for these models are based on randomized embedding of the graph into a tree (HST) and then solving the problem on this tree. We show that this is not…

Data Structures and Algorithms · Computer Science 2020-04-20 Yossi Azar , Noam Touitou

We present a new approximation algorithm for the treewidth problem which finds an upper bound on the treewidth and constructs a corresponding tree decomposition as well. Our algorithm is a faster variation of Reed's classical algorithm. For…

Data Structures and Algorithms · Computer Science 2022-06-24 Mahdi Belbasi , Martin Fürer

We present simple deterministic algorithms for subgraph finding and enumeration in the broadcast CONGEST model of distributed computation: -- For any constant $k$, detecting $k$-paths and trees on $k$ nodes can be done in $O(1)$ rounds. --…

Distributed, Parallel, and Cluster Computing · Computer Science 2017-09-22 Janne H. Korhonen , Joel Rybicki

We show that the eccentricities, diameter, radius, and Wiener index of an undirected $n$-vertex graph with nonnegative edge lengths can be computed in time $O(n\cdot \binom{k+\lceil\log n\rceil}{k} \cdot 2^k k^2 \log n)$, where $k$ is the…

Data Structures and Algorithms · Computer Science 2018-05-21 Karl Bringmann , Thore Husfeldt , Måns Magnusson

The stabiliser formalism plays a central role in quantum computing, error correction, and fault tolerance. Conversions between and verifications of different specifications of stabiliser states and Clifford gates are important components of…

Quantum Physics · Physics 2025-01-09 Nadish de Silva , Wilfred Salmon , Ming Yin

Clifford geometric algebras of multivectors are treated in detail. These algebras are build over a graded space and exhibit a grading or multivector structure. The careful study of the endomorphisms of this space makes it clear, that…

High Energy Physics - Theory · Physics 2015-06-26 Bertfried Fauser

These are lecture notes for a course on the theory of Clifford algebras, with special emphasis on their wide range of applications in mathematics and physics. Clifford algebra is introduced both through a conventional tensor algebra…

Mathematical Physics · Physics 2009-07-31 Douglas Lundholm , Lars Svensson

Clifford gates play a role in the optimisation of Clifford+T circuits. Reducing the count and the depth of Clifford gates, as well as the optimal scheduling of T gates, influence the hardware and the time costs of executing quantum…

Quantum Physics · Physics 2019-06-18 Alexandru Paler , Robert Basmadjian

Fixed parameter tractable algorithms for bounded treewidth are known to exist for a wide class of graph optimization problems. While most research in this area has been focused on exact algorithms, it is hard to find decompositions of…

Data Structures and Algorithms · Computer Science 2016-10-05 Thomas Bosman

We give an algorithm that for an input n-vertex graph G and integer k>0, in time 2^[O(k)]n either outputs that the treewidth of G is larger than k, or gives a tree decomposition of G of width at most 5k+4. This is the first algorithm…

Data Structures and Algorithms · Computer Science 2013-04-24 Hans Bodlaender , Pål G. Drange , Markus S. Dregi , Fedor V. Fomin , Daniel Lokshtanov , Michał Pilipczuk

We consider global problems, i.e. problems that take at least diameter time, even when the bandwidth is not restricted. We show that all problems considered admit efficient solutions in low-treewidth graphs. By ``efficient'' we mean that…

Distributed, Parallel, and Cluster Computing · Computer Science 2022-05-31 Taisuke Izumi , Naoki Kitamura , Takamasa Naruse , Gregory Schwartzman

In this paper, we present a Branch and Bound algorithm called QuickBB for computing the treewidth of an undirected graph. This algorithm performs a search in the space of perfect elimination ordering of vertices of the graph. The algorithm…

Data Structures and Algorithms · Computer Science 2012-07-19 Vibhav Gogate , Rina Dechter

The kernel method is a potential approach to analyzing structured data such as sequences, trees, and graphs; however, unordered trees have not been investigated extensively. Kimura et al. (2011) proposed a kernel function for unordered…

Data Structures and Algorithms · Computer Science 2012-06-22 Daisuke Kimura , Hisashi Kashima

We develop a framework for applying treewidth-based dynamic programming on graphs with "hybrid structure", i.e., with parts that may not have small treewidth but instead possess other structural properties. Informally, this is achieved by…

Data Structures and Algorithms · Computer Science 2019-08-28 Eduard Eiben , Robert Ganian , Thekla Hamm , O-joung Kwon