Download or read book Regular b Groups Degenerating Riemann Surfaces and Spectral Theory written by Dennis A. Hejhal and published by American Mathematical Soc.. This book was released on 1990 with total page 146 pages. Available in PDF, EPUB and Kindle. Book excerpt: This paper is concerned with the spectral theory of the Laplacian as the underlying Riemann surface is "pinched down" to a surface with nodes. The problem is attacked from the (general) standpoint of regular b-groups and the Selberg trace formula.

Download or read book Spectral Asymptotics on Degenerating Hyperbolic 3 Manifolds written by Józef Dodziuk and published by American Mathematical Soc.. This book was released on 1998 with total page 90 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this volume, the authors study asymptotics of the geometry and spectral theory of degenerating sequences of finite volume hyperbolic manifolds of three dimensions. Thurston's hyperbolic surgery theorem assets the existence of non-trivial sequences of finite volume hyperbolic three manifolds which converge to a three manifold with additional cusps. In the geometric aspect of their study, the authors use the convergence of hyperbolic metrics on the thick parts of the manifolds under consideration to investigate convergentce of tubes in the manifolds of the sequence to cusps of the limiting manifold. In the specral theory aspect of the work, they prove convergence of heat kernels. They then define a regualrized heat race associated to any finite volume, complete, hyperbolic three manifold, and study its asymptotic behaviour through degeneration. As an application of the analysis of the regularized heat trace, they study asymptotic behaviours of the spectral zeta function, determinant of the Laplacian, Selberg zeta function, and spectral counting functions through degeneration. The authors' methods are an adaptation to three dimensions of the earlier work of Jorgenson and Lundelius who investigated the asymptotic behaviour of spectral functions on degenerating families of finite area hyperbolic Riemann surfaces.

Download or read book Dynamical Spectral and Arithmetic Zeta Functions written by Michel Laurent Lapidus and published by American Mathematical Soc.. This book was released on 2001 with total page 210 pages. Available in PDF, EPUB and Kindle. Book excerpt: The original zeta function was studied by Riemann as part of his investigation of the distribution of prime numbers. Other sorts of zeta functions were defined for number-theoretic purposes, such as the study of primes in arithmetic progressions. This led to the development of $L$-functions, which now have several guises. It eventually became clear that the basic construction used for number-theoretic zeta functions can also be used in other settings, such as dynamics, geometry, and spectral theory, with remarkable results. This volume grew out of the special session on dynamical, spectral, and arithmetic zeta functions held at the annual meeting of the American Mathematical Society in San Antonio, but also includes four articles that were invited to be part of the collection. The purpose of the meeting was to bring together leading researchers, to find links and analogies between their fields, and to explore new methods. The papers discuss dynamical systems, spectral geometry on hyperbolic manifolds, trace formulas in geometry and in arithmetic, as well as computational work on the Riemann zeta function. Each article employs techniques of zeta functions. The book unifies the application of these techniques in spectral geometry, fractal geometry, and number theory. It is a comprehensive volume, offering up-to-date research. It should be useful to both graduate students and confirmed researchers.

Download or read book Kernel Functions Analytic Torsion and Moduli Spaces written by John David Fay and published by American Mathematical Soc.. This book was released on 1992 with total page 137 pages. Available in PDF, EPUB and Kindle. Book excerpt: This memoir is a study of Ray-Singer analytic torsion for hermitian vector bundles on a compact Riemann surface [italic]C. The torsion is expressed through the trace of a modified resolvent. Thus, one can develop perturbation-curvature formulae for the Green-Szegö kernel and also for the torsion in terms of the Ahlfors-Bers complex structure of the Teichmuller space and Mumford complex structure of the moduli space of stable bundles of degree zero on [italic]C.

Download or read book Minimal Surfaces in Riemannian Manifolds written by Min Ji and published by American Mathematical Soc.. This book was released on 1993 with total page 63 pages. Available in PDF, EPUB and Kindle. Book excerpt: A multiple solution theory to the Plateau problem in a Riemannian manifold is established. In [italic capital]S[superscript italic]n, the existence of two solutions to this problem is obtained. The Morse-Tompkins-Shiffman Theorem is extended to the case when the ambient space admits no minimal sphere.

Download or read book Coarse Cohomology and Index Theory on Complete Riemannian Manifolds written by John Roe and published by American Mathematical Soc.. This book was released on 1993 with total page 106 pages. Available in PDF, EPUB and Kindle. Book excerpt: "July 1993, volume 104, number 497 (fourth of 6 numbers)."

Download or read book Orientation and the Leray Schauder Theory for Fully Nonlinear Elliptic Boundary Value Problems written by Patrick Fitzpatrick and published by American Mathematical Soc.. This book was released on 1993-01-01 with total page 145 pages. Available in PDF, EPUB and Kindle. Book excerpt: The aim of this work is to develop an additive, integer-valued degree theory for the class of quasilinear Fredholm mappings. This class is sufficiently large that, within its framework, one can study general fully nonlinear elliptic boundary value problems. A degree for the whole class of quasilinear Fredholm mappings must necessarily accommodate sign-switching of the degree along admissible homotopies. The authors introduce ''parity'', a homotopy invariant of paths of linear Fredholm operators having invertible endpoints. The parity provides a complete description of the possible changes in sign of the degree and thereby permits use of the degree to prove multiplicity and bifurcation theorems for quasilinear Fredholm mappings. Applications are given to the study of fully nonlinear elliptic boundary value problems.

Download or read book Enright Shelton Theory and Vogan s Problem for Generalized Principal Series written by Brian D. Boe and published by American Mathematical Soc.. This book was released on 1993 with total page 122 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book investigates the composition series of generalized principal series representations induced from a maximal cuspidal parabolic subgroup of a real reductive Lie group. Boe and Collingwood study when such representations are multiplicity-free (Vogan's Problem #3) and the problem of describing their composition factors in closed form. The results obtained are strikingly similar to those of Enright and Shelton for highest weight modules. Connections with two different flag variety decompositions are discussed.

Download or read book On the Existence of Feller Semigroups with Boundary Conditions written by Kazuaki Taira and published by American Mathematical Soc.. This book was released on 1992 with total page 81 pages. Available in PDF, EPUB and Kindle. Book excerpt: This paper is devoted to the functional analytic approach to the problem of construction of Feller semigroups with Ventcel' (Wentzell) boundary conditions. This paper considers the non-transversal case and solves from the viewpoint of functional analysis the problem of construction of Feller semigroups for elliptic Waldenfels operators. Intuitively, our result may be stated as follows: One can construct a Feller semigroup corresponding to such a diffusion phenomenon that a Markovian particle moves both by jumps and continuously in the state space until it "dies" at which time it reaches the set where the absorption phenomenon occurs.

Download or read book Invariant Subsemigroups of Lie Groups written by Karl-Hermann Neeb and published by American Mathematical Soc.. This book was released on 1993 with total page 209 pages. Available in PDF, EPUB and Kindle. Book excerpt: First we investigate the structure of Lie algebras with invariant cones and give a characterization of those Lie algebras containing pointed and generating invariant cones. Then we study the global structure of invariant Lie semigroups, and how far Lie's third theorem remains true for invariant cones and Lie semigroups.

Download or read book Eigenvalues of the Laplacian for Hecke Triangle Groups written by Dennis A. Hejhal and published by American Mathematical Soc.. This book was released on 1992 with total page 177 pages. Available in PDF, EPUB and Kindle. Book excerpt: Paper I is concerned with computational aspects of the Selberg trace formalism, considering the usual type of eigenfunction and including an analysis of pseudo cusp forms and their residual effects. Paper II examines the modular group PSL (2, [bold]Z), as such groups have both a discrete and continuous spectrum. This paper only examines the discrete side of the spectrum.

Download or read book The Subregular Germ of Orbital Integrals written by Thomas Callister Hales and published by American Mathematical Soc.. This book was released on 1992 with total page 161 pages. Available in PDF, EPUB and Kindle. Book excerpt: An integral formula for the subregular germ of a [italic small capital]K-orbital integral is developed. The formula holds for any reductive group over a [italic]p-adic field of characteristic zero. This expression of the subregular germ is obtained by applying Igusa's theory of asymptotic expansions. The integral formula is applied to the question of the transfer of a [italic small capital]K-orbital integral to an endoscopic group. It is shown that the quadratic characters arising in the subregular germs are compatible with the transfer. Details of the transfer are given for the subregular germ of unitary groups.

Download or read book Constant Mean Curvature Immersions of Enneper Type written by Henry C. Wente and published by American Mathematical Soc.. This book was released on 1992 with total page 90 pages. Available in PDF, EPUB and Kindle. Book excerpt: This memoir is devoted to the case of constant mean curvature surfaces immersed in [bold]R3. We reduce this geometrical problem to finding certain integrable solutions to the Gauss equation. Many new and interesting examples are presented, including immersed cylinders in [bold]R3 with embedded Delaunay ends and [italic]n-lobes in the middle, and one-parameter families of immersed constant mean curvature tori in [bold]R3. We examine minimal surfaces in hyperbolic three-space, which is in some ways the most complicated case.

Download or read book Selberg Trace Formulae and Equidistribution Theorems for Closed Geodesics and Laplace written by Steven Zelditch and published by American Mathematical Soc.. This book was released on 1992 with total page 113 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work is concerned with a pair of dual asymptotics problems on a finite-area hyperbolic surface. The first problem is to determine the distribution of closed geodesics in the unit tangent bundle. The second problem is to determine the distribution of eigenfunctions (in microlocal sense) in the unit tangent bundle.

Download or read book Vertex Algebras and Integral Bases for the Enveloping Algebras of Affine Lie Algebras written by Shari A. Prevost and published by American Mathematical Soc.. This book was released on 1992 with total page 113 pages. Available in PDF, EPUB and Kindle. Book excerpt: We present a new proof of the identities needed to exhibit an explicit [bold]Z-basis for the universal enveloping algebra associated to an affine Lie algebra. We then use the explicit [bold]Z-bases to extend Borcherds' description, via vertex operator representations, of a [bold]Z-form of the enveloping algebras for the simply-laced affine Lie algebras to the enveloping algebras associated to the unequal root length affine Lie algebras.

Download or read book Semistability of Amalgamated Products and HNN Extensions written by Michael L. Mihalik and published by American Mathematical Soc.. This book was released on 1992 with total page 98 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this work, the authors show that amalgamated products and HNN-extensions of finitely presented semistable at infinity groups are also semistable at infinity. A major step toward determining whether all finitely presented groups are semistable at infinity, this result easily generalizes to finite graphs of groups. The theory of group actions on trees and techniques derived from the proof of Dunwoody's accessibility theorem are key ingredients in this work.

Download or read book Extension of Positive Definite Distributions and Maximum Entropy written by Jean-Pierre Gabardo and published by American Mathematical Soc.. This book was released on 1993 with total page 111 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this work, the maximum entropy method is used to solve the extension problem associated with a positive-definite function, or distribution, defined on an interval of the real line. Garbardo computes explicitly the entropy maximizers corresponding to various logarithmic integrals depending on a complex parameter and investigates the relation to the problem of uniqueness of the extension. These results are based on a generalization, in both the discrete and continuous cases, of Burg's maximum entropy theorem.