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126 full-text articles. Page 1 of 5.

Topological And Hq Equivalence Of Prime Cyclic P-Gonal Actions On Riemann Surfaces, Sean A. Broughton 2016 Rose-Hulman Institute of Technology

Topological And Hq Equivalence Of Prime Cyclic P-Gonal Actions On Riemann Surfaces, Sean A. Broughton

Mathematical Sciences Technical Reports (MSTR)

Two Riemann surfaces S1 and S2 with conformal G-actions have topologically equivalent actions if there is a homeomorphism h : S1 -> S2 which intertwines the actions. A weaker equivalence may be defined by comparing the representations of G on the spaces of holomorphic q-differentials Hq(S1) and Hq(S2). In this note we study the differences between topological equivalence and Hq equivalence of prime cyclic actions, where S1/G and S2/G have genus zero.


The Implicit Function Theorem And Free Algebraic Sets, Jim Agler, John E. McCarthy 2016 Washington University in St Louis

The Implicit Function Theorem And Free Algebraic Sets, Jim Agler, John E. Mccarthy

Mathematics Faculty Publications

We prove an implicit function theorem for non-commutative functions. We use this to show that if p ( X;Y ) is a generic non-commuting polynomial in two variables, and X is a generic matrix, then all solutions Y of p ( X;Y ) = 0 will commute with X


Aspects Of Non-Commutative Function Theory, Jim Agler, John E. McCarthy 2016 Washington University in St Louis

Aspects Of Non-Commutative Function Theory, Jim Agler, John E. Mccarthy

Mathematics Faculty Publications

We discuss non commutative functions, which naturally arise when dealing with functions of more than one matrix variable.


Analytic Geometry And Calculus I (Syllabus), Shaun Ault, Sudhir Goel 2016 Valdosta State University

Analytic Geometry And Calculus I (Syllabus), Shaun Ault, Sudhir Goel

Mathematics Syllabi and Reports

This syllabus was created under a Round Two ALG Textbook Transformation Grant.


Algebraicity Of Rational Hodge Isometries Of K3 Surfaces, Nikolay Buskin 2016 University of Massachusetts Amherst

Algebraicity Of Rational Hodge Isometries Of K3 Surfaces, Nikolay Buskin

Doctoral Dissertations May 2014 - current

Consider any rational Hodge isometry

$\psi:H^2(S_1,\QQ)\rightarrow H^2(S_2,\QQ)$ between any two K\"ahler $K3$

surfaces $S_1$ and $S_2$. We prove that the cohomology class of $\psi$ in $H^{2,2}(S_1\times S_2)$

is a polynomial in Chern classes of coherent analytic sheaves

over $S_1 \times S_2$. Consequently, the cohomology class of $\psi$ is algebraic

whenever $S_1$ and $S_2$ are algebraic.


Topology Of The Affine Springer Fiber In Type A, Tobias Wilson 2016 University of Massachusetts - Amherst

Topology Of The Affine Springer Fiber In Type A, Tobias Wilson

Doctoral Dissertations May 2014 - current

We develop algorithms for describing elements of the affine Springer fiber in type

A for certain 2 g(C[[t]]). For these , which are equivalued, integral, and regular,

it is known that the affine Springer fiber, X, has a paving by affines resulting from

the intersection of Schubert cells with X. Our description of the elements of Xallow

us to understand these affine spaces and write down explicit dimension formulae. We

also explore some closure relations between the affine spaces and begin to describe the

moment map for the both the regular and extended torus action.


Quasi-Platonic Psl2(Q)-Actions On Closed Riemann Surfaces, Sean A. Broughton 2015 Rose-Hulman Institute of Technology

Quasi-Platonic Psl2(Q)-Actions On Closed Riemann Surfaces, Sean A. Broughton

Mathematical Sciences Technical Reports (MSTR)

This paper is the first of two papers whose combined goal is to explore the dessins d'enfant and symmetries of quasi-platonic actions of PSL2(q). A quasi-platonic action of a group G on a closed Riemann S surface is a conformal action for which S/G is a sphere and S->S/G is branched over {0, 1,infinity}. The unit interval in S/G may be lifted to a dessin d'enfant D, an embedded bipartite graph in S. The dessin forms the edges and vertices of a tiling on S by dihedrally symmetric polygons, generalizing the ...


Quasi-Platonic Psl2(Q)-Actions On Closed Riemann Surfaces, Sean Broughton 2015 Rose-Hulman Institute of Technology

Quasi-Platonic Psl2(Q)-Actions On Closed Riemann Surfaces, Sean Broughton

S. Allen Broughton

This paper is the first of two papers whose combined goal is to explore the dessins d'enfant and symmetries of quasi-platonic actions of PSL2(q). A quasi-platonic action of a group G on a closed Riemann S surface is a conformal action for which S/G is a sphere and S->S/G is branched over {0, 1,infinity}. The unit interval in S/G may be lifted to a dessin d'enfant D, an embedded bipartite graph in S. The dessin forms the edges and vertices of a tiling on S by dihedrally symmetric polygons, generalizing the ...


Integrability And Regularity Of Rational Functions, Greg Knese 2015 Washington University in St. Louis

Integrability And Regularity Of Rational Functions, Greg Knese

Mathematics Faculty Publications

Motivated by recent work in the mathematics and engineering literature, we study integrability and non-tangential regularity on the two-torus for rational functions that are holomorphic on the bidisk. One way to study such rational functions is to fix the denominator and look at the ideal of polynomials in the numerator such that the rational function is square integrable. A concrete list of generators is given for this ideal as well as a precise count of the dimension of the subspace of numerators with a specified bound on bidegree. The dimension count is accomplished by constructing a natural pair of commuting ...


Quasi-Platonic Psl(2,Q)-Actions On Closed Riemann Surfaces, Sean Broughton 2015 Rose-Hulman Institute of Technology

Quasi-Platonic Psl(2,Q)-Actions On Closed Riemann Surfaces, Sean Broughton

S. Allen Broughton

This paper is the first of two papers whose combined goal is to explore the dessins d'enfant and symmetries of quasi-platonic actions of PSL(2,q). A quasi-platonic action of a group G on a closed Riemann S surface is a conformal action for which S/G is a sphere and S -> S/G is
branched over {0,1,infinity}. The unit interval in S/G may be lifted to a dessin d'enfant D, an embedded bipartite graph in S.The dessin forms the edges and vertices of a tiling on S by dihedrally symmetric polygons, generalizing the ...


A Study Of Green’S Relations On Algebraic Semigroups, Allen O'Hara 2015 The University of Western Ontario

A Study Of Green’S Relations On Algebraic Semigroups, Allen O'Hara

Electronic Thesis and Dissertation Repository

The purpose of this work is to enhance the understanding regular algebraic semigroups by considering the structural influence of Green's relations. There will be three chief topics of discussion.

  • Green's relations and the Adherence order on reductive monoids
  • Renner’s conjecture on regular irreducible semigroups with zero
  • a Green’s relation inspired construction of regular algebraic semigroups

Primarily, we will explore the combinatorial and geometric nature of reductive monoids with zero. Such monoids have a decomposition in terms of a Borel subgroup, called the Bruhat decomposition, which produces a finite monoid, R, the Renner monoid. We will explore ...


Algorithms To Compute Characteristic Classes, Martin Helmer 2015 The University of Western Ontario

Algorithms To Compute Characteristic Classes, Martin Helmer

Electronic Thesis and Dissertation Repository

In this thesis we develop several new algorithms to compute characteristics classes in a variety of settings. In addition to algorithms for the computation of the Euler characteristic, a classical topological invariant, we also give algorithms to compute the Segre class and Chern-Schwartz-MacPherson (CSM) class. These invariants can in turn be used to compute other common invariants such as the Chern-Fulton class (or the Chern class in smooth cases).

We begin with subschemes of a projective space over an algebraically closed field of characteristic zero. In this setting we give effective algorithms to compute the CSM class, Segre class and ...


Symbolic Powers Of Edge Ideals, Mike Janssen 2015 Dordt College

Symbolic Powers Of Edge Ideals, Mike Janssen

Faculty Work: Comprehensive List

No abstract provided.


Manipulating The Mass Distribution Of A Golf Putter, Paul J. Hessler Jr. 2015 University of Rhode Island

Manipulating The Mass Distribution Of A Golf Putter, Paul J. Hessler Jr.

Senior Honors Projects

Putting may appear to be the easiest but is actually the most technically challenging part of the game of golf. The ideal putting stroke will remain parallel to its desired trajectory both in the reverse and forward direction when the putter head is within six inches of the ball. Deviation from this concept will cause a cut or sidespin on the ball that will affect the path the ball will travel.

Club design plays a large part in how well a player will be able to achieve a straight back and straight through club head path near impact; specifically the ...


Automorphisms Of Graph Curves On K3 Surfaces, Joshua C. Ferrerra 2015 Georgia Southern University

Automorphisms Of Graph Curves On K3 Surfaces, Joshua C. Ferrerra

Electronic Theses & Dissertations

We examine the automorphism group of configurations of rational curves on $K3$ surfaces. We use the properties of finite automorphisms of $\PP^1$ to examine what restrictions a given elliptic fibration imposes on the possible finite order non-symplectic automorphisms of the $K3$ surface. We also examine the fixed loci of these automorphisms, and construct an explicit fibration to demonstrate the process.


Computing Intersection Multiplicity Via Triangular Decomposition, Paul Vrbik 2014 The University of Western Ontario

Computing Intersection Multiplicity Via Triangular Decomposition, Paul Vrbik

Electronic Thesis and Dissertation Repository

Fulton’s algorithm is used to calculate the intersection multiplicity of two plane curves about a rational point. This work extends Fulton’s algorithm first to algebraic points (encoded by triangular sets) and then, with some generic assumptions, to l many hypersurfaces.

Out of necessity, we give a standard-basis free method (i.e. practically efficient method) for calculating tangent cones at points on curves.


A Note On Characters Of Algebraic Groups, Sean Broughton 2014 Rose-Hulman Institute of Technology

A Note On Characters Of Algebraic Groups, Sean Broughton

S. Allen Broughton

It is proven that a nowhere-vanishing polynomial function on a connected algebraic group, over an algebraically closed field, is a multiple of a (one-dimensional) character..


The Homology And Higher Representations Of The Automorphism Group Of A Riemann Surface, Sean Broughton 2014 Rose-Hulman Institute of Technology

The Homology And Higher Representations Of The Automorphism Group Of A Riemann Surface, Sean Broughton

S. Allen Broughton

The representations of the automorphism group of a compact Riemann surface on the first homology group and the spaces of q-differentials are decomposed into irreducibles. As an application it is shown that M24 is not a Hurwitz group.


Symmetries Of Accola-Machlaclan And Kulkarni Surfaces, Sean Broughton, Emilio Bujalance, Antonio Costa, Gregorz Gromadski 2014 Rose-Hulman Institute of Technology

Symmetries Of Accola-Machlaclan And Kulkarni Surfaces, Sean Broughton, Emilio Bujalance, Antonio Costa, Gregorz Gromadski

S. Allen Broughton

For all g > 1 there is a Riemann surface of genus g whose automorphism group has order 8g+8, establishing a lower bound for the possible orders of automorphism groups of Riemann surfaces. Accola and Maclachlan established the existence of such surfaces; we shall call them Accola-Maclachlan surfaces. Later Kulkarni proved that for suffciently large g the Accola-Maclachlan surface was unique for g = 0,1, 2 mod 4 and produced exactly one additional surface (the Kulkarni surface) for g = 3 mod 4. In this paper we determine the symmetries of these special surfaces, computing the number of ovals and the ...


Simple Group Actions On Hyperbolic Surfaces Of Least Area, Sean Broughton 2014 Rose-Hulman Institute of Technology

Simple Group Actions On Hyperbolic Surfaces Of Least Area, Sean Broughton

S. Allen Broughton

It is shown that if a simple group G acts conformally on a hyperbolic surface of least area (or alternatively, on a Riemann surface of least genus σ ≥ 2), then G is normal in Aut(S) and the map Aut(S) → Aut(G) induced by conjugation is injective. For the preponderance of these minimal actions the group Aut(S)/G is isomorphic to a subgroup of Σ3. It is shown how to compute Aut(S) purely in terms of the group–theoretic structure of G, in these cases. As examples and as part of the proof, the minimal actions and ...


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