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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

On Monoids Related to Braid Groups and Transformation Semigroups

East, James Phillip Hinton January 2006 (has links)
PhD / None.
12

Kombinatorische Geometrie der Stokesregionen

Yu, Jianming. January 1990 (has links)
Thesis (doctoral)--Rheinische Friedrich-Wilhelms-Universität Bonn, 1990. / Includes bibliographical references (p. 114.
13

The theory of knots and associated problems

Garside, F. A. January 1965 (has links)
No description available.
14

Quantum Toroidal Superalgebras

Pereira Bezerra, Luan 05 1900 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / We introduce the quantum toroidal superalgebra E(m|n) associated with the Lie superalgebra gl(m|n) and initiate its study. For each choice of parity "s" of gl(m|n), a corresponding quantum toroidal superalgebra E(s) is defined. To show that all such superalgebras are isomorphic, an action of the toroidal braid group is constructed. The superalgebra E(s) contains two distinguished subalgebras, both isomorphic to the quantum affine superalgebra Uq sl̂(m|n) with parity "s", called vertical and horizontal subalgebras. We show the existence of Miki automorphism of E(s), which exchanges the vertical and horizontal subalgebras. If m and n are different and "s" is standard, we give a construction of level 1 E(m|n)-modules through vertex operators. We also construct an evaluation map from E(m|n)(q1,q2,q3) to the quantum affine algebra Uq gl̂(m|n) at level c=q3^(m-n)/2.
15

Composite circular braid mechanics

Hopper, Robert Huston 18 April 2009 (has links)
Braided composites find many diverse applications in modern technology and tailoring the mechanical properties of these structures has become increasingly important. This thesis will examine one class of circular braids encompassing an elastic core. By hypothesizing four modes of operation and incorporating primary influences, the mechanical response of the composite is predicted based on its initial parameters and material properties. The ability to model the yarns that constitute the braid as nonlinear materials enables the simulated response to span finite deformations. A scheme for nondimensionalizing the model parameters and governing equations for each mode of operation is also proposed and implemented. In an effort to validate the assumptions underlying the model's formulation, a series of experimental trials are documented that verify the fundamental braid mechanics. A wide variety of analytical cases are also introduced to investigate the influences of various model parameters. Possible extensions for the existing model are also noted. / Master of Science
16

Matematická teorie žonglování / The mathematical theory of juggling

Zamboj, Michal January 2014 (has links)
Title: The mathematical theory of juggling Author: Bc. Michal Zamboj Department: Department of Mathematics Education Supervisor: RNDr. Antonín Slavík, Ph.D. Abstract: This diploma thesis extends the bachelor thesis of the same name. It deals with the graphic representation of juggling sequences by the cyclic diagram. Using the Burnside theorem and cyclic diagrams, we calculate the number of all genera- tors of juggling sequences. The relation between juggling and the theory of braids is described as well. The mathematical model of inside and outside throws is made from an empirical observation of trajectories of balls. Braids of juggling sequences and their attributes are provided using a real model of ladder. A sketch of the proof of the theorem that any braid is juggleable is given as well.
17

Braids, transverse links and knot Floer homology:

Tovstopyat-Nelip, Lev Igorevich January 2019 (has links)
Thesis advisor: John A. Baldwin / Contact geometry has played a central role in many recent advances in low-dimensional topology; e.g. in showing that knot Floer homology detects the genus of a knot and whether a knot is fibered. It has also been used to show that the unknot, trefoil, and figure eight knot are determined by their Dehn surgeries. An important problem in 3-dimensional contact geometry is the classification of Legendrian and transverse knots. Such knots come equipped with some classical invariants. New invariants from knot Floer homology have been effective in distinguishing Legendrian and transverse knots with identical classical invariants, a notoriously difficult task. The Giroux correspondence allows contact structures to be studied via purely topological constructs called open book decompositions. Transverse links are then braids about these open books, which in turn may be thought of as mapping tori of diffeomorphisms of compact surfaces with boundary having marked points, which we refer to as pointed monodromies. In the first part of this thesis, we investigate properties of the transverse invariant in knot Floer homology, in particular its behavior for transverse closures of pointed monodromies possessing certain dynamical properties. The binding of an open book sits naturally as a transverse link in the supported contact manifold. We prove that the transverse link invariant in knot Floer homology of the binding union any braid about the open book is non-zero. As an application, we show that any pointed monodromy with fractional Dehn twist coefficient greater than one has non-zero transverse invariant, generalizing a result of Plamenevskaya for braids about the unknot. In the second part of this thesis, we define invariants of Legendrian and transverse links in universally tight lens spaces using grid diagrams, generalizing those defined by Ozsvath, Szabo and Thurston. We show that our invariants are equivalent to those defined by Lisca, Ozsvath, Szabo and Stipsicz for Legendrian and transverse links in arbitrary contact 3-manifolds. Our argument involves considering braids about rational open book decompositions and filtrations on knot Floer complexes. / Thesis (PhD) — Boston College, 2019. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Mathematics.
18

Properties and applications of the annular filtration on Khovanov homology

Hubbard, Diana D. January 2016 (has links)
Thesis advisor: Julia E. Grigsby / The first part of this thesis is on properties of annular Khovanov homology. We prove a connection between the Euler characteristic of annular Khovanov homology and the classical Burau representation for closed braids. This yields a straightforward method for distinguishing, in some cases, the annular Khovanov homologies of two closed braids. As a corollary, we obtain the main result of the first project: that annular Khovanov homology is not invariant under a certain type of mutation on closed braids that we call axis-preserving. The second project is joint work with Adam Saltz. Plamenevskaya showed in 2006 that the homology class of a certain distinguished element in Khovanov homology is an invariant of transverse links. In this project we define an annular refinement of this element, kappa, and show that while kappa is not an invariant of transverse links, it is a conjugacy class invariant of braids. We first discuss examples that show that kappa is non-trivial. We then prove applications of kappa relating to braid stabilization and spectral sequences, and we prove that kappa provides a new solution to the word problem in the braid group. Finally, we discuss definitions and properties of kappa in the reduced setting. / Thesis (PhD) — Boston College, 2016. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Mathematics.
19

Representações do grupo de tranças por automorfismos de grupos / Representaciones ddelç grupo de trenzas por automorfismos de grupo

Pizarro, Pavel Jesus Henriquez 16 January 2012 (has links)
A partir de um grupo H e um elemento h em H, nós definimos uma representação : \'B IND. n\' Aut(\'H POT. n\' ), onde \'B IND. n\' denota o grupo de trança de n cordas, e \'H POT. n\' denota o produto livre de n cópias de H. Chamamos a a representação de tipo Artin associada ao par (H, h). Nós também estudamos varios aspectos de tal representação. Primeiramente, associamos a cada trança um grupo \' IND. (H,h)\' () e provamos que o operador \' IND. (H,h)\' determina um grupo invariante de enlaçamentos orientados. Então damos uma construção topológica da representação de tipo Artin e do invariante de enlaçamentos \' IND.(H,h)\' , e provamos que a representação é fiel se, e somente se, h é não trivial / From a group H and a element h H, we define a representation : \' B IND. n\' Aut(\'H POT. n\'), where \'B IND. n\' denotes the braid group on n strands, and \'H POT. n\' denotes the free product of n copies of H. We call the Artin type representation associated to the pair (H, h). Here we study various aspects of such representations. Firstly, we associate to each braid a group \' IND. (H,h)\' () and prove that the operator \' IND. (H,h)\' determines a group invariant of oriented links. We then give a topological construction of the Artin type representations and of the link invariant \' iND. (H,h)\' , and we prove that the Artin type representations are faithful if and only if h is nontrivial
20

A propriedade de Borsuk-Ulam para funções entre superfícies / The Borsuk-Ulam property for functions between surfaces

Laass, Vinicius Casteluber 21 July 2015 (has links)
Sejam $M$ e $N$ superfícies fechadas e $\\tau: M \\to M$ uma involução livre de pontos fixos. Dizemos que uma classe de homotopia $\\beta \\in [M,N]$ tem a propriedade de Borsuk-Ulam se para toda função contínua $g: M \\to N$ que representa $\\beta$, existe $x \\in M$ tal que $g(\\tau(x)) = g(x)$. No caso em que $N$ é diferente de $S^2$ e $RP^2$, mostramos que $\\beta$ não ter a propriedade de Borsuk-Ulam é equivalente a existência de um diagrama algébrico envolvendo $\\pi_1(M)$, $\\pi_1(M_\\tau)$, $P_2(N)$ e $B_2(N)$, sendo $M_\\tau$ o espaço de órbitas de $\\tau$ e sendo $P_2 (N)$ e $B_2(N)$, respectivamente, o grupo de tranças puras e totais de $N$. Para cada caso listado abaixo, nós classificamos todas as classes de homotopia $\\beta \\in [M,N]$ que têm a propriedade de Borsuk-Ulam: $M = T^2$, $M_\\tau = T^2$ e $N = T^2$; $M = T^2$, $M_\\tau = K^2$ e $N = T^2$; $M = K^2$ e $N = T^2$; $M = T^2$, $M_\\tau = T^2$ e $N = K^2$. No caso em que $N = S^2$, para cada superfície $M$ e involução $\\tau: M \\to M$, nós classificamos os elementos $\\beta \\in [M,S^2]$ que têm a propriedade de Borsuk-Ulam. Para fazer tal classificação, nós usamos a teoria de funções equivariantes e a teoria de grau de aplicações. Para classes de homotopia $\\beta \\in [M,RP^2]$, classificamos aquelas que se levantam para $S^2$. No final, nós consideramos a propriedade de Borsuk-Ulam para ações livres de $Z_p$, com $p$ um inteiro primo positivo. Neste caso, mostramos que se $M$ e $N$ são superfícies fechadas e $Z_p$ age livremente em M, com $p$ ímpar, então sempre existe uma função $f: M \\to N$ homotópica a uma função constante e cuja restrição a cada órbita da ação é injetora. / Let $M$ and $N$ be compact surfaces without boundary, and let $\\tau: M \\to M$ be a fixed-point free involution. We say that a homotopy class $\\beta \\in [M,N]$ has the Borsuk-Ulam property if for every continuous fuction $g: M \\to N$ that represents $\\beta$, there exists $x \\in M$ such that $g(\\tau(x)) = g(x)$. In the case where $N$ is different of $S^2$ and $RP^2$, we show that the fact that $\\beta$ does not have the Borsuk-Ulam property is equivalent to the existence of an algebraic diagram involving $\\pi_1(M)$, $\\pi_1(M_\\tau), $P_2(N)$ and $B_2(N)$, where $M_\\tau$ is the orbit space of $\\tau$ and $P_2(N)$ and $B_2(N) $ are the pure and the full braid groups of the surface $N$ respectively. We then go on to consider the cases of the torus $T^2$ and the Klein bottle $K^2$. Let $M$ and $N$ satisfy one of the following: $M = T^2$, $M_\\tau = T^2$ and $N = T^2$; $M = T^2$, $M_\\tau = K^2$ and $N = T^2$; $M = K^2$ and $N = T^2$; $M = T^2$, $M_\\tau = T^2$ and $N = K^2$. In these cases we classify the homotopy classes $\\beta \\in [M,N]$ that possess the Borsuk-Ulam property. If $N= S^2$, for every surface $M$ and an involution $\\tau: M \\to M$, we classify the elements $\\beta \\in [M, S^2] $ that possess the Borsuk-Ulam property. To obtain this classification, we make use of the theory of equivariant functions and degree theory of maps. For homotopy classes $\\beta \\in [M,RP^2]$, we classify the classes that admit a lifting to $S^2$. Finally, we consider the Borsuk-Ulam property for free actions of $Z_p$, where $p$ is a prime number. If $M$ and $N$ are compact surfaces without boundary such that $Z_p$ acts freely on $M$, with $p$ odd, we show that there is always a function $f: M \\to N$ homotopic to the constant function whose restriction to every orbit of $\\tau$ is injective.

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