This thesis studies the geometry of hyperbolic monopoles using supersymmetry in four and six dimensions. On the one hand, we show that starting with a four dimensional supersymmetric Yang-Mills theory provides the necessary information to study the geometry of the complex moduli space of hyperbolic monopoles. On the other hand, we require to start with a six dimensional supersymmetric Yang-Mills theory to study the geometry of the real moduli space of hyperbolic monopoles. In chapter two, we construct an off-shell supersymmetric Yang-Mills-Higgs theory with complex fields on three-dimensional hyperbolic space starting from an on-shell supersymmetric Yang-Mills theory on four-dimensional Euclidean space. We, then, show that hyperbolic monopoles coincide precisely with the configurations that preserve one half of the supersymmetry. In chapter three, we explore the geometry of the moduli space of hyperbolic monopoles using the low energy linearization of the field equations. We find that the complexified tangent bundle to the hyperbolic moduli space has a 2-sphere worth of integrable structures that act complex linearly and behave like unit imaginary quaternions. Moreover, we show that these complex structures are parallel with respect to the Obata connection, which implies that the geometry of the complexified moduli space of hyperbolic monopoles is hypercomplex. We also show, as a requirement of analysing the geometry, that there is a one-to-one correspondence between the number of solutions of the linearized Bogomol’nyi equation on hyperbolic space and the number of solutions of the Dirac equation in the presence of hyperbolic monopole. In chapter four and five, we shift the focus to supersymmetric Yang-Mills theories in six dimensional Minkowskian spacetime. Via dimensional reduction we construct a supersymmetric Yang-Mills Higgs theory on R3 with real fields which we then promote to H3. Under certain supersymmetric constraints, we show that hyperbolic monopoles configurations of this theory preserve, again, one half of the supersymmetry. Then, through investigating the geometry of the moduli space we showthat the moduli space is described by real coordinate functions (zero modes), and we construct two sets of 2-sphere of real complex structures that act linearly on the tangent bundle of the moduli space, but don’t behave like unit quaternions. This result coincides with the result of Bielawski and Schwachhöfer, who called this new type of geometry pluricomplex geometry. Finally, we show that in the limiting case, when the radius of curvature H3 is set to infinity, the geometry becomes hyperkähler which is the geometry of the moduli space of Euclidian monopoles.

A dissertation submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Master of Science. Johannesburg, 2013. / Continued fractions have been extensively studied in number theoretic ways. These continued fractions are expressed as compositions of M¨obius maps in the Picard group PS L(2;C) that act, by Poincar´e’s extension, as isometries on H3. We investigate the Picard group with its generators and derive the fundamental domain using a direct method. From the fundamental domain, we produce an ideal octahedron, O0, that generates the Farey tessellation of H3. We explore the properties of Farey neighbours, Farey geodesics and Farey triangles that arise from the Farey tessellation and relate these to Ford spheres. We consider the Farey addition of two rationals in R as a subdivision of an interval and hence are able to generalise this notion to a subdivision of a Farey triangle with Gaussian Farey neighbour vertices. This Farey set allows us to revisit the Farey triangle subdivision given by Schmidt [44] and interpret it as a theorem about adjacent octahedra in the Farey tessellation of H3. We consider continued fraction algorithms with Gaussian integer coe cients. We introduce an analogue of Series [45] cutting sequence across H2 in H3. We derive a continued fraction expansion based on this cutting sequence generated by a geodesic in H3 that ends at the point in C that passes through O0.

Thesis advisor: Martin Bridgeman / We begin this dissertation by studying the relationship between the Poincaré metric of a simply connected domain Ω ⊂ ℂ and the geometry of Dome(Ω), the boundary of the convex hull of its complement. Sullivan showed that there is a universal constant K[subscript]eq[subscript] such that one may find a conformally natural K[subscript]eq[subscript]-quasiconformal map from Ω to Dome(Ω) which extends to the identity on ∂Ω. Explicit upper and lower bounds on K[subscript]eq[subscript] have been obtained by Epstein, Marden, Markovic and Bishop. We improve upon these upper bounds by showing that one may choose K[subscript]eq[subscript] ≤ 7.1695. As part of this work, we provide stronger criteria for embeddedness of pleated planes. In addition, for Kleinian groups Γ where N = ℍ³/Γ has incompressible boundary, we give improved bounds for the average bending on the convex core of N and the Lipschitz constant for the homotopy inverse of the nearest point retraction. In the second part of this dissertation, we prove an extension of Basmajian's identity to n-Hitchin representations of compact bordered surfaces. For 3-Hitchin representations, we provide a geometric interpretation of this identity analogous to Basmajian's original result. As part of our proof, we demonstrate that for a closed surface, the Lebesgue measure on the Frenet curve of an n-Hitchin representation is zero on the limit set of any incompressible subsurface. This generalizes a classical result in hyperbolic geometry. In our final chapter, we prove the Bridgeman-Kahn identity for all finite volume hyperbolic n-manifolds with totally geodesic boundary. As part of this work, we correct a commonly referenced expression of the volume form on the unit tangent bundle of ℍⁿ in terms of the geodesic end point parametrization. / Thesis (PhD) — Boston College, 2016. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Mathematics.

Thesis advisor: Robert Meyerhoff / Thurston showed that for all but a finite number of Dehn Surgeries on a cusped hyperbolic 3-manifold, the resulting manifold admits a hyperbolic structure. Global bounds on this number have been set, and gradually improved upon, by a number of Mathematicians until Lackenby and Meyerhoff proved the sharp bound of 10, which is realized by the figure-eight knot exterior. We improve this result by proving a stronger version of Gordon’s conjecture: that excluding the figure-eight knot exterior, cusped hyperbolic 3-manifolds have at most 8 non-hyperbolic Dehn Surgeries. To do so we make use of the work of Gabai et. al. from a forthcoming paper which parameterizes measurements of the cusp, then uses a rigorous computer aided search of the space to classify all hyperbolic 3-manifolds up to a specified cusp size. Their approach hinges on the discreteness of manifold points in the parameter space, an assumption which cannot be made if the manifolds have infinite volume. In this paper we also show that infinite-volume manifolds, which must be Free Bicuspid, can have cusp volume as low as 3.159. As such, these manifolds are a concern for any future expansion of the approach of Gabai et. al. / Thesis (PhD) — Boston College, 2018. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Mathematics.

In this dissertation, we study etale correspondence of hyperbolic curves with unbounded dynamics. Mochizuki proved that over a field of characteristic 0, such curves are always Shimura curves. We explore variants of this question in positive characteristic, using graph theory, l-adic local systems, and Barsotti-Tate groups. Given a correspondence with unbounded dynamics, we construct an infinite graph with a large group of ”algebraic” automorphisms and roughly measures the ”generic dynamics” of the correspondence. We construct a specialization map to a graph representing the actual dynamics. Along the way, we formulate conjectures that etale correspondences with unbounded dynamics behave similarly to Hecke correspondences of Shimura curves. Using graph theory, we show that type (3,3) etale correspondences verify various parts of this philosophy. Key in the second half of this dissertation is a recent p-adic Langlands correspondence, due to Abe, which answers affirmatively the petites camarades conjecture of Deligne in the case of curves. This allows us the build a correspondence between rank 2 l-adic local systems with trivial determinant and Frobenius traces in Q and certain height 2, dimension 1 Barsotti-Tate groups. We formulate a conjecture on the fields of definitions of certain compatible systems of l-adic representations. Relatedly, we conjecture that the Barsotti-Tate groups over complete curves in positive characteristic may be ”algebraized” to abelian schemes.

Wong Tak Kwong. / Thesis submitted in: August 2004. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (leaves 67-72). / Abstracts in English and Chinese. / Chapter 1 --- Introduction --- p.6 / Chapter 1.1 --- Basic Notations --- p.7 / Chapter 1.2 --- Riemann Problems --- p.10 / Chapter 1.3 --- Elementary Waves --- p.10 / Chapter 1.3.1 --- Rarefaction Waves --- p.11 / Chapter 1.3.2 --- Shock Waves --- p.11 / Chapter 1.3.3 --- Composite Waves --- p.13 / Chapter 1.4 --- Remarks --- p.14 / Chapter 2 --- Non-strictly Hyperbolic Conservation Laws --- p.16 / Chapter 2.1 --- Systems with Isolated Umbilic Degeneracy --- p.16 / Chapter 2.1.1 --- Mathematical Motivations --- p.17 / Chapter 2.2 --- Complex Burgers' Equation --- p.21 / Chapter 2.2.1 --- Introduction --- p.21 / Chapter 2.2.2 --- Basic Properties --- p.22 / Chapter 2.2.3 --- Riemann Solutions --- p.24 / Chapter 2.2.4 --- Under-Compressive Shocks --- p.31 / Chapter 3 --- Relaxation Approximation --- p.34 / Chapter 3.1 --- Basic Ideas of the Relaxation Approximation --- p.34 / Chapter 3.1.1 --- General Settings --- p.35 / Chapter 3.1.2 --- Subcharacteristic Condition --- p.36 / Chapter 3.2 --- Relaxation of Scalar Conservation Laws --- p.39 / Chapter 3.2.1 --- Perturbation Problems --- p.39 / Chapter 3.3 --- Jin-Xin Relaxation Systems --- p.42 / Chapter 3.3.1 --- Basic Ideas of the Jin-Xin Systems --- p.42 / Chapter 3.4 --- Zero-Relaxation Limit --- p.45 / Chapter 3.4.1 --- 2x2 Hyperbolic Relaxation Systems --- p.45 / Chapter 3.4.2 --- Jin-Xin Relaxation Systems --- p.48 / Chapter 4 --- Jin-Xin Relaxation Limit for the Complex Burgers' Equations --- p.51 / Chapter 4.1 --- Jin-Xin Relaxation Limit for the UCUI Solutions --- p.52 / Chapter 4.1.1 --- Main Statements --- p.52 / Chapter 4.1.2 --- Analysis on UCUI Solution --- p.53 / Chapter 4.1.3 --- Shock Profiles --- p.56 / Chapter 4.1.4 --- Re-scaled Relaxation System --- p.60 / Chapter 4.1.5 --- Proof of Theorem 4.1.1.3 --- p.63 / Bibliography --- p.67

Xiao, Jingjing. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (p. 46-50). / Abstracts in English and Chinese. / Abstract --- p.i / Acknowledgement --- p.ii / Chapter 1 --- Introduction --- p.1 / Chapter 2 --- Backgrounds and Our Main Results --- p.4 / Chapter 2.1 --- Backgrounds --- p.4 / Chapter 2.1.1 --- The Scalar Case --- p.4 / Chapter 2.1.2 --- 2x2 Systems --- p.5 / Chapter 2.1.3 --- General n x n(n ≥ 3) Systems --- p.9 / Chapter 2.2 --- Our Main Results --- p.18 / Chapter 3 --- Lifespan of Periodic Solutions to Gas Dynamics Systems --- p.21 / Chapter 3.1 --- Riemann Invariant Formulation --- p.21 / Chapter 3.2 --- Calculation along Characteristics --- p.26 / Chapter 3.3 --- Estimate of the Global Wave Interaction --- p.35 / Chapter 3.4 --- Proof of Theorem 2.2.1 --- p.38 / Chapter 4 --- Proof of Theorem 2.2.2 and a Special Case --- p.40 / Chapter 4.1 --- Proof of Theorem 2.2.2 --- p.40 / Chapter 4.2 --- A Special Case --- p.43 / Chapter 5 --- Appendix --- p.45

Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Mathematics, 1981. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE. / Bibliography: leaf 80. / by Mark David Baker. / Ph.D.

Thesis (M.S.)--University of Delaware, 2006. / Principal faculty advisor: A.D. Kirwan, College of Marine and Earth Studies. Includes bibliographical references.

In this paper, we discuss the local and global existence of week solutions for some hyperbolic-parabolic systems modelling chemotaxis.