On Some Aspects of Oscillation Theory and Geometry

On Some Aspects of Oscillation Theory and Geometry PDF Author: Bruno Bianchini
Publisher: American Mathematical Soc.
ISBN: 0821887998
Category : Mathematics
Languages : en
Pages : 208

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Book Description
The aim of this paper is to analyze some of the relationships between oscillation theory for linear ordinary differential equations on the real line (shortly, ODE) and the geometry of complete Riemannian manifolds. With this motivation the authors prove some new results in both directions, ranging from oscillation and nonoscillation conditions for ODE's that improve on classical criteria, to estimates in the spectral theory of some geometric differential operator on Riemannian manifolds with related topological and geometric applications. To keep their investigation basically self-contained, the authors also collect some, more or less known, material which often appears in the literature in various forms and for which they give, in some instances, new proofs according to their specific point of view.

On Some Aspects of Oscillation Theory and Geometry

On Some Aspects of Oscillation Theory and Geometry PDF Author: Bruno Bianchini
Publisher: American Mathematical Soc.
ISBN: 0821887998
Category : Mathematics
Languages : en
Pages : 208

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Book Description
The aim of this paper is to analyze some of the relationships between oscillation theory for linear ordinary differential equations on the real line (shortly, ODE) and the geometry of complete Riemannian manifolds. With this motivation the authors prove some new results in both directions, ranging from oscillation and nonoscillation conditions for ODE's that improve on classical criteria, to estimates in the spectral theory of some geometric differential operator on Riemannian manifolds with related topological and geometric applications. To keep their investigation basically self-contained, the authors also collect some, more or less known, material which often appears in the literature in various forms and for which they give, in some instances, new proofs according to their specific point of view.

Geometric Analysis of Quasilinear Inequalities on Complete Manifolds

Geometric Analysis of Quasilinear Inequalities on Complete Manifolds PDF Author: Bruno Bianchini
Publisher: Springer Nature
ISBN: 3030627047
Category : Mathematics
Languages : en
Pages : 291

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Book Description
This book demonstrates the influence of geometry on the qualitative behaviour of solutions of quasilinear PDEs on Riemannian manifolds. Motivated by examples arising, among others, from the theory of submanifolds, the authors study classes of coercive elliptic differential inequalities on domains of a manifold M with very general nonlinearities depending on the variable x, on the solution u and on its gradient. The book highlights the mean curvature operator and its variants, and investigates the validity of strong maximum principles, compact support principles and Liouville type theorems. In particular, it identifies sharp thresholds involving curvatures or volume growth of geodesic balls in M to guarantee the above properties under appropriate Keller-Osserman type conditions, which are investigated in detail throughout the book, and discusses the geometric reasons behind the existence of such thresholds. Further, the book also provides a unified review of recent results in the literature, and creates a bridge with geometry by studying the validity of weak and strong maximum principles at infinity, in the spirit of Omori-Yau’s Hessian and Laplacian principles and subsequent improvements.

Cohomology for Quantum Groups via the Geometry of the Nullcone

Cohomology for Quantum Groups via the Geometry of the Nullcone PDF Author: Christopher P. Bendel
Publisher: American Mathematical Soc.
ISBN: 0821891758
Category : Mathematics
Languages : en
Pages : 110

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Book Description
In general, little is known about the representation theory of quantum groups (resp., algebraic groups) when l (resp., p ) is smaller than the Coxeter number h of the underlying root system. For example, Lusztig's conjecture concerning the characters of the rational irreducible G -modules stipulates that p=h. The main result in this paper provides a surprisingly uniform answer for the cohomology algebra H (u ? ,C) of the small quantum group.

Combinatorial Floer Homology

Combinatorial Floer Homology PDF Author: Vin de Silva
Publisher: American Mathematical Soc.
ISBN: 0821898868
Category : Mathematics
Languages : en
Pages : 126

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Book Description
The authors define combinatorial Floer homology of a transverse pair of noncontractible nonisotopic embedded loops in an oriented -manifold without boundary, prove that it is invariant under isotopy, and prove that it is isomorphic to the original Lagrangian Floer homology. Their proof uses a formula for the Viterbo-Maslov index for a smooth lune in a -manifold.

Near Soliton Evolution for Equivariant Schrodinger Maps in Two Spatial Dimensions

Near Soliton Evolution for Equivariant Schrodinger Maps in Two Spatial Dimensions PDF Author: Ioan Bejenaru
Publisher: American Mathematical Soc.
ISBN: 0821892150
Category : Mathematics
Languages : en
Pages : 120

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Book Description
The authors consider the Schrödinger Map equation in 2+1 dimensions, with values into \mathbb{S}^2. This admits a lowest energy steady state Q, namely the stereographic projection, which extends to a two dimensional family of steady states by scaling and rotation. The authors prove that Q is unstable in the energy space \dot H^1. However, in the process of proving this they also show that within the equivariant class Q is stable in a stronger topology X \subset \dot H^1.

On the Spectra of Quantum Groups

On the Spectra of Quantum Groups PDF Author: Milen Yakimov
Publisher: American Mathematical Soc.
ISBN: 082189174X
Category : Mathematics
Languages : en
Pages : 104

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Book Description
Joseph and Hodges-Levasseur (in the A case) described the spectra of all quantum function algebras on simple algebraic groups in terms of the centers of certain localizations of quotients of by torus invariant prime ideals, or equivalently in terms of orbits of finite groups. These centers were only known up to finite extensions. The author determines the centers explicitly under the general conditions that the deformation parameter is not a root of unity and without any restriction on the characteristic of the ground field. From it he deduces a more explicit description of all prime ideals of than the previously known ones and an explicit parametrization of .

Nonlinear Stability of Ekman Boundary Layers in Rotating Stratified Fluids

Nonlinear Stability of Ekman Boundary Layers in Rotating Stratified Fluids PDF Author: Hajime Koba
Publisher: American Mathematical Soc.
ISBN: 0821891332
Category : Mathematics
Languages : en
Pages : 142

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Book Description
A stationary solution of the rotating Navier-Stokes equations with a boundary condition is called an Ekman boundary layer. This book constructs stationary solutions of the rotating Navier-Stokes-Boussinesq equations with stratification effects in the case when the rotating axis is not necessarily perpendicular to the horizon. The author calls such stationary solutions Ekman layers. This book shows the existence of a weak solution to an Ekman perturbed system, which satisfies the strong energy inequality. Moreover, the author discusses the uniqueness of weak solutions and computes the decay rate of weak solutions with respect to time under some assumptions on the Ekman layers and the physical parameters. The author also shows that there exists a unique global-in-time strong solution of the perturbed system when the initial datum is sufficiently small. Comparing a weak solution satisfying the strong energy inequality with the strong solution implies that the weak solution is smooth with respect to time when time is sufficiently large.

A Complete Classification of the Isolated Singularities for Nonlinear Elliptic Equations with Inverse Square Potentials

A Complete Classification of the Isolated Singularities for Nonlinear Elliptic Equations with Inverse Square Potentials PDF Author: Florica C. Cîrstea
Publisher: American Mathematical Soc.
ISBN: 0821890220
Category : Mathematics
Languages : en
Pages : 97

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Book Description
In particular, for b = 1 and λ = 0, we find a sharp condition on h such that the origin is a removable singularity for all non-negative solutions of [[eqref]]one, thus addressing an open question of Vázquez and Véron.

Spectra of Symmetrized Shuffling Operators

Spectra of Symmetrized Shuffling Operators PDF Author: Victor Reiner
Publisher: American Mathematical Soc.
ISBN: 0821890956
Category : Mathematics
Languages : en
Pages : 121

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Book Description
For a finite real reflection group W and a W -orbit O of flats in its reflection arrangement - or equivalently a conjugacy class of its parabolic subgroups - the authors introduce a statistic noninv O (w) on w in W that counts the number of O -noninversions of w . This generalises the classical (non-)inversion statistic for permutations w in the symmetric group S n. The authors then study the operator ? O of right-multiplication within the group algebra CW by the element that has noninv O (w) as its coefficient on w.

Topics in Modern Differential Geometry

Topics in Modern Differential Geometry PDF Author: Stefan Haesen
Publisher: Springer
ISBN: 9462392404
Category : Mathematics
Languages : en
Pages : 284

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Book Description
A variety of introductory articles is provided on a wide range of topics, including variational problems on curves and surfaces with anisotropic curvature. Experts in the fields of Riemannian, Lorentzian and contact geometry present state-of-the-art reviews of their topics. The contributions are written on a graduate level and contain extended bibliographies. The ten chapters are the result of various doctoral courses which were held in 2009 and 2010 at universities in Leuven, Serbia, Romania and Spain.