Author: L. Gaunce Lewis
Publisher: American Mathematical Soc.
ISBN: 082182046X
Category : Mathematics
Languages : en
Pages : 106
Book Description
This book is intended for graduate students and research mathematicians interested in algebraic topology.
Splitting Theorems for Certain Equivariant Spectra
Author: L. Gaunce Lewis
Publisher: American Mathematical Soc.
ISBN: 082182046X
Category : Mathematics
Languages : en
Pages : 106
Book Description
This book is intended for graduate students and research mathematicians interested in algebraic topology.
Publisher: American Mathematical Soc.
ISBN: 082182046X
Category : Mathematics
Languages : en
Pages : 106
Book Description
This book is intended for graduate students and research mathematicians interested in algebraic topology.
Splitting Theorems for Certain Equivariant Spectra
Author:
Publisher: American Mathematical Soc.
ISBN: 9780821864098
Category : Mathematics
Languages : en
Pages : 108
Book Description
Let $G$ be a compact Lie group, $\Pi$ be a normal subgroup of $G$, $\mathcal G=G/\Pi$, $X$ be a $\mathcal G$-space and $Y$ be a $G$-space. There are a number of results in the literature giving a direct sum decomposition of the group $[\Sigma^\infty X,\Sigma^\infty Y]_G$ of equivariant stable homotopy classes of maps from $X$ to $Y$. Here, these results are extended to a decomposition of the group $[B,C]_G$ of equivariant stable homotopy classes of maps from an arbitrary finite $\mathcal G$-CW sptrum $B$ to any $G$-spectrum $C$ carrying a geometric splitting (a new type of structure introduced here). Any naive $G$-spectrum, and any spectrum derived from such by a change of universe functor, carries a geometric splitting. Our decomposition of $[B,C]_G$ is a consequence of the fact that, if $C$ is geometrically split and $(\mathfrak F',\mathfrak F)$ is any reasonable pair of families of subgroups of $G$, then there is a splitting of the cofibre sequence $(E\mathfrak F_+ \wedge C)^\Pi \longrightarrow (E\mathfrak F'_+ \wedge C)^\Pi \longrightarrow (E(\mathfrak F', \mathfrak F) \wedge C)^\Pi$ constructed from the universal spaces for the families. Both the decomposition of the group $[B,C]_G$ and the splitting of the cofibre sequence are proven here not just for complete $G$-universes, but for arbitrary $G$-universes. Various technical results about incomplete $G$-universes that should be of independent interest are also included in this paper. These include versions of the Adams and Wirthmuller isomorphisms for incomplete universes. Also included is a vanishing theorem for the fixed-point spectrum $(E(\mathfrak F',\mathfrak F) \wedge C)^\Pi$ which gives computational force to the intuition that what really matters about a $G$-universe $U$ is which orbits $G/H$ embed as $G$-spaces in $U$.
Publisher: American Mathematical Soc.
ISBN: 9780821864098
Category : Mathematics
Languages : en
Pages : 108
Book Description
Let $G$ be a compact Lie group, $\Pi$ be a normal subgroup of $G$, $\mathcal G=G/\Pi$, $X$ be a $\mathcal G$-space and $Y$ be a $G$-space. There are a number of results in the literature giving a direct sum decomposition of the group $[\Sigma^\infty X,\Sigma^\infty Y]_G$ of equivariant stable homotopy classes of maps from $X$ to $Y$. Here, these results are extended to a decomposition of the group $[B,C]_G$ of equivariant stable homotopy classes of maps from an arbitrary finite $\mathcal G$-CW sptrum $B$ to any $G$-spectrum $C$ carrying a geometric splitting (a new type of structure introduced here). Any naive $G$-spectrum, and any spectrum derived from such by a change of universe functor, carries a geometric splitting. Our decomposition of $[B,C]_G$ is a consequence of the fact that, if $C$ is geometrically split and $(\mathfrak F',\mathfrak F)$ is any reasonable pair of families of subgroups of $G$, then there is a splitting of the cofibre sequence $(E\mathfrak F_+ \wedge C)^\Pi \longrightarrow (E\mathfrak F'_+ \wedge C)^\Pi \longrightarrow (E(\mathfrak F', \mathfrak F) \wedge C)^\Pi$ constructed from the universal spaces for the families. Both the decomposition of the group $[B,C]_G$ and the splitting of the cofibre sequence are proven here not just for complete $G$-universes, but for arbitrary $G$-universes. Various technical results about incomplete $G$-universes that should be of independent interest are also included in this paper. These include versions of the Adams and Wirthmuller isomorphisms for incomplete universes. Also included is a vanishing theorem for the fixed-point spectrum $(E(\mathfrak F',\mathfrak F) \wedge C)^\Pi$ which gives computational force to the intuition that what really matters about a $G$-universe $U$ is which orbits $G/H$ embed as $G$-spaces in $U$.
On the Connection between Weighted Norm Inequalities, Commutators and Real Interpolation
Author: Jesús Bastero
Publisher: American Mathematical Soc.
ISBN: 0821827340
Category : Mathematics
Languages : en
Pages : 94
Book Description
Introduction Calderon weights Applications to real interpolation: reiteration and extrapolation Other classes of weights Extrapolation of weighted norm inequalities via extrapolation theory Applications to function spaces Commutators defined by the K-method Generalized commutators The quasi Banach case Applications to harmonic analysis BMO type spaces associated to Calderon weights Atomic decompositions and duality References.
Publisher: American Mathematical Soc.
ISBN: 0821827340
Category : Mathematics
Languages : en
Pages : 94
Book Description
Introduction Calderon weights Applications to real interpolation: reiteration and extrapolation Other classes of weights Extrapolation of weighted norm inequalities via extrapolation theory Applications to function spaces Commutators defined by the K-method Generalized commutators The quasi Banach case Applications to harmonic analysis BMO type spaces associated to Calderon weights Atomic decompositions and duality References.
Analytic Quotients
Author: Ilijas Farah
Publisher: American Mathematical Soc.
ISBN: 0821821172
Category : Mathematics
Languages : en
Pages : 201
Book Description
This book is intended for graduate students and research mathematicians interested in set theory.
Publisher: American Mathematical Soc.
ISBN: 0821821172
Category : Mathematics
Languages : en
Pages : 201
Book Description
This book is intended for graduate students and research mathematicians interested in set theory.
Gorenstein Liaison, Complete Intersection Liaison Invariants and Unobstructedness
Author: Jan Oddvar Kleppe
Publisher: American Mathematical Soc.
ISBN: 0821827383
Category : Mathematics
Languages : en
Pages : 130
Book Description
This paper contributes to the liaison and obstruction theory of subschemes in $\mathbb{P}^n$ having codimension at least three. The first part establishes several basic results on Gorenstein liaison. A classical result of Gaeta on liaison classes of projectively normal curves in $\mathbb{P}^3$ is generalized to the statement that every codimension $c$ ``standard determinantal scheme'' (i.e. a scheme defined by the maximal minors of a $t\times (t+c-1)$ homogeneous matrix), is in the Gorenstein liaison class of a complete intersection. Then Gorenstein liaison (G-liaison) theory is developed as a theory of generalized divisors on arithmetically Cohen-Macaulay schemes. In particular, a rather general construction of basic double G-linkage is introduced, which preserves the even G-liaison class. This construction extends the notion of basic double linkage, which plays a fundamental role in the codimension two situation. The second part of the paper studies groups which are invariant under complete intersection linkage, and gives a number of geometric applications of these invariants. Several differences between Gorenstein and complete intersection liaison are highlighted. For example, it turns out that linearly equivalent divisors on a smooth arithmetically Cohen-Macaulay subscheme belong, in general, to different complete intersection liaison classes, but they are always contained in the same even Gorenstein liaison class. The third part develops the interplay between liaison theory and obstruction theory and includes dimension estimates of various Hilbert schemes. For example, it is shown that most standard determinantal subschemes of codimension $3$ are unobstructed, and the dimensions of their components in the corresponding Hilbert schemes are computed.
Publisher: American Mathematical Soc.
ISBN: 0821827383
Category : Mathematics
Languages : en
Pages : 130
Book Description
This paper contributes to the liaison and obstruction theory of subschemes in $\mathbb{P}^n$ having codimension at least three. The first part establishes several basic results on Gorenstein liaison. A classical result of Gaeta on liaison classes of projectively normal curves in $\mathbb{P}^3$ is generalized to the statement that every codimension $c$ ``standard determinantal scheme'' (i.e. a scheme defined by the maximal minors of a $t\times (t+c-1)$ homogeneous matrix), is in the Gorenstein liaison class of a complete intersection. Then Gorenstein liaison (G-liaison) theory is developed as a theory of generalized divisors on arithmetically Cohen-Macaulay schemes. In particular, a rather general construction of basic double G-linkage is introduced, which preserves the even G-liaison class. This construction extends the notion of basic double linkage, which plays a fundamental role in the codimension two situation. The second part of the paper studies groups which are invariant under complete intersection linkage, and gives a number of geometric applications of these invariants. Several differences between Gorenstein and complete intersection liaison are highlighted. For example, it turns out that linearly equivalent divisors on a smooth arithmetically Cohen-Macaulay subscheme belong, in general, to different complete intersection liaison classes, but they are always contained in the same even Gorenstein liaison class. The third part develops the interplay between liaison theory and obstruction theory and includes dimension estimates of various Hilbert schemes. For example, it is shown that most standard determinantal subschemes of codimension $3$ are unobstructed, and the dimensions of their components in the corresponding Hilbert schemes are computed.
Estimating the Error of Numerical Solutions of Systems of Reaction-Diffusion Equations
Author: Donald J. Estep
Publisher: American Mathematical Soc.
ISBN: 0821820729
Category : Mathematics
Languages : en
Pages : 125
Book Description
This paper is concerned with the computational estimation of the error of numerical solutions of potentially degenerate reaction-diffusion equations. The underlying motivation is a desire to compute accurate estimates as opposed to deriving inaccurate analytic upper bounds. In this paper, we outline, analyze, and test an approach to obtain computational error estimates based on the introduction of the residual error of the numerical solution and in which the effects of the accumulation of errors are estimated computationally. We begin by deriving an a posteriori relationship between the error of a numerical solution and its residual error using a variational argument. This leads to the introduction of stability factors, which measure the sensitivity of solutions to various kinds of perturbations. Next, we perform some general analysis on the residual errors and stability factors to determine when they are defined and to bound their size. Then we describe the practical use of the theory to estimate the errors of numerical solutions computationally. Several key issues arise in the implementation that remain unresolved and we present partial results and numerical experiments about these points. We use this approach to estimate the error of numerical solutions of nine standard reaction-diffusion models and make a systematic comparison of the time scale over which accurate numerical solutions can be computed for these problems. We also perform a numerical test of the accuracy and reliability of the computational error estimate using the bistable equation. Finally, we apply the general theory to the class of problems that admit invariant regions for the solutions, which includes seven of the main examples. Under this additional stability assumption, we obtain a convergence result in the form of an upper bound on the error from the a posteriori error estimate. We conclude by discussing the preservation of invariant regions under discretization.
Publisher: American Mathematical Soc.
ISBN: 0821820729
Category : Mathematics
Languages : en
Pages : 125
Book Description
This paper is concerned with the computational estimation of the error of numerical solutions of potentially degenerate reaction-diffusion equations. The underlying motivation is a desire to compute accurate estimates as opposed to deriving inaccurate analytic upper bounds. In this paper, we outline, analyze, and test an approach to obtain computational error estimates based on the introduction of the residual error of the numerical solution and in which the effects of the accumulation of errors are estimated computationally. We begin by deriving an a posteriori relationship between the error of a numerical solution and its residual error using a variational argument. This leads to the introduction of stability factors, which measure the sensitivity of solutions to various kinds of perturbations. Next, we perform some general analysis on the residual errors and stability factors to determine when they are defined and to bound their size. Then we describe the practical use of the theory to estimate the errors of numerical solutions computationally. Several key issues arise in the implementation that remain unresolved and we present partial results and numerical experiments about these points. We use this approach to estimate the error of numerical solutions of nine standard reaction-diffusion models and make a systematic comparison of the time scale over which accurate numerical solutions can be computed for these problems. We also perform a numerical test of the accuracy and reliability of the computational error estimate using the bistable equation. Finally, we apply the general theory to the class of problems that admit invariant regions for the solutions, which includes seven of the main examples. Under this additional stability assumption, we obtain a convergence result in the form of an upper bound on the error from the a posteriori error estimate. We conclude by discussing the preservation of invariant regions under discretization.
Complexes Associated to Two Vectors and a Rectangular Matrix
Author: Andrew R. Kustin
Publisher: American Mathematical Soc.
ISBN: 0821820737
Category : Mathematics
Languages : en
Pages : 97
Book Description
This book is intended for graduate student and research mathematicians interested in commutative rings and algebras.
Publisher: American Mathematical Soc.
ISBN: 0821820737
Category : Mathematics
Languages : en
Pages : 97
Book Description
This book is intended for graduate student and research mathematicians interested in commutative rings and algebras.
Dynamical Zeta Functions, Nielsen Theory and Reidemeister Torsion
Author: Alexander Fel'shtyn
Publisher: American Mathematical Soc.
ISBN: 0821820907
Category : Mathematics
Languages : en
Pages : 165
Book Description
In the paper we study new dynamical zeta functions connected with Nielsen fixed point theory. The study of dynamical zeta functions is part of the theory of dynamical systems, but it is also intimately related to algebraic geometry, number theory, topology and statistical mechanics. The paper consists of four parts. Part I presents a brief account of the Nielsen fixed point theory. Part II deals with dynamical zeta functions connected with Nielsen fixed point theory. Part III is concerned with analog of Dold congruences for the Reidemeister and Nielsen numbers. In Part IV we explain how dynamical zeta functions give rise to the Reidemeister torsion, a very important topological invariant which has useful applications in knots theory,quantum field theory and dynamical systems.
Publisher: American Mathematical Soc.
ISBN: 0821820907
Category : Mathematics
Languages : en
Pages : 165
Book Description
In the paper we study new dynamical zeta functions connected with Nielsen fixed point theory. The study of dynamical zeta functions is part of the theory of dynamical systems, but it is also intimately related to algebraic geometry, number theory, topology and statistical mechanics. The paper consists of four parts. Part I presents a brief account of the Nielsen fixed point theory. Part II deals with dynamical zeta functions connected with Nielsen fixed point theory. Part III is concerned with analog of Dold congruences for the Reidemeister and Nielsen numbers. In Part IV we explain how dynamical zeta functions give rise to the Reidemeister torsion, a very important topological invariant which has useful applications in knots theory,quantum field theory and dynamical systems.
The Decomposition and Classification of Radiant Affine 3-Manifolds
Author: Suhyoung Choi
Publisher: American Mathematical Soc.
ISBN: 0821827049
Category : Mathematics
Languages : en
Pages : 137
Book Description
An affine manifold is a manifold with torsion-free flat affine connection - a geometric topologist would define it as a manifold with an atlas of charts to the affine space with affine transition functions. This title is an in-depth examination of the decomposition and classification of radiant affine 3-manifolds - affine manifolds of the type that have a holonomy group consisting of affine transformations fixing a common fixed point.
Publisher: American Mathematical Soc.
ISBN: 0821827049
Category : Mathematics
Languages : en
Pages : 137
Book Description
An affine manifold is a manifold with torsion-free flat affine connection - a geometric topologist would define it as a manifold with an atlas of charts to the affine space with affine transition functions. This title is an in-depth examination of the decomposition and classification of radiant affine 3-manifolds - affine manifolds of the type that have a holonomy group consisting of affine transformations fixing a common fixed point.
On the Foundations of Nonlinear Generalized Functions I and II
Author: Michael Grosser
Publisher: American Mathematical Soc.
ISBN: 0821827294
Category : Mathematics
Languages : en
Pages : 113
Book Description
In part 1 of this title the authors construct a diffeomorphism invariant (Colombeau-type) differential algebra canonically containing the space of distributions in the sense of L. Schwartz. Employing differential calculus in infinite dimensional (convenient) vector spaces, previous attempts in this direction are unified and completed. Several classification results are achieved and applications to nonlinear differential equations involving singularities are given.
Publisher: American Mathematical Soc.
ISBN: 0821827294
Category : Mathematics
Languages : en
Pages : 113
Book Description
In part 1 of this title the authors construct a diffeomorphism invariant (Colombeau-type) differential algebra canonically containing the space of distributions in the sense of L. Schwartz. Employing differential calculus in infinite dimensional (convenient) vector spaces, previous attempts in this direction are unified and completed. Several classification results are achieved and applications to nonlinear differential equations involving singularities are given.