Generative Complexity in Algebra

Generative Complexity in Algebra PDF Author: Joel Berman
Publisher: American Mathematical Soc.
ISBN: 0821837079
Category : Mathematics
Languages : en
Pages : 176

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Book Description
Considers the behavior of $\mathrm{G}_\mathcal{C}(k)$ when $\mathcal{C}$ is a locally finite equational class (variety) of algebras and $k$ is finite. This title looks at ways that algebraic properties of $\mathcal{C}$ lead to upper or lower bounds on generative complexity.

Generative Complexity in Algebra

Generative Complexity in Algebra PDF Author: Joel Berman
Publisher: American Mathematical Soc.
ISBN: 0821837079
Category : Mathematics
Languages : en
Pages : 176

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Book Description
Considers the behavior of $\mathrm{G}_\mathcal{C}(k)$ when $\mathcal{C}$ is a locally finite equational class (variety) of algebras and $k$ is finite. This title looks at ways that algebraic properties of $\mathcal{C}$ lead to upper or lower bounds on generative complexity.

Generative Complexity in Algebra

Generative Complexity in Algebra PDF Author: Joel Berman
Publisher:
ISBN: 9781470404291
Category : Algebraic varieties
Languages : en
Pages : 159

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Book Description
Introduction Background material Part 1. Introducing Generative Complexity: Definitions and examples Semilattices and lattices Varieties with a large number of models Upper bounds Categorical invariants Part 2. Varieties with Few Models: Types 4 or 5 need not apply Semisimple may apply Permutable may also apply Forcing modular behavior Restricting solvable behavior Varieties with very few models Restricting nilpotent behavior Decomposing finite algebras Restricting affine behavior A characterization theorem Part 3. Conclusions: Application to groups and rings Open problems Tables Bibliography

A Generative Theory of Shape

A Generative Theory of Shape PDF Author: Michael Leyton
Publisher: Springer
ISBN: 3540454888
Category : Computers
Languages : en
Pages : 559

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Book Description
The purpose of this book is to develop a generative theory of shape that has two properties we regard as fundamental to intelligence –(1) maximization of transfer: whenever possible, new structure should be described as the transfer of existing structure; and (2) maximization of recoverability: the generative operations in the theory must allow maximal inferentiability from data sets. We shall show that, if generativity satis?es these two basic criteria of - telligence, then it has a powerful mathematical structure and considerable applicability to the computational disciplines. The requirement of intelligence is particularly important in the gene- tion of complex shape. There are plenty of theories of shape that make the generation of complex shape unintelligible. However, our theory takes the opposite direction: we are concerned with the conversion of complexity into understandability. In this, we will develop a mathematical theory of und- standability. The issue of understandability comes down to the two basic principles of intelligence - maximization of transfer and maximization of recoverability. We shall show how to formulate these conditions group-theoretically. (1) Ma- mization of transfer will be formulated in terms of wreath products. Wreath products are groups in which there is an upper subgroup (which we will call a control group) that transfers a lower subgroup (which we will call a ?ber group) onto copies of itself. (2) maximization of recoverability is insured when the control group is symmetry-breaking with respect to the ?ber group.

Invariant Means and Finite Representation Theory of $C^*$-Algebras

Invariant Means and Finite Representation Theory of $C^*$-Algebras PDF Author: Nathanial Patrick Brown
Publisher: American Mathematical Soc.
ISBN: 0821839160
Category : Mathematics
Languages : en
Pages : 122

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Book Description
Various subsets of the tracial state space of a unital C$*$-algebra are studied. The largest of these subsets has a natural interpretation as the space of invariant means. II$ 1$-factor representations of a class of C$*$-algebras considered by Sorin Popa are also studied. These algebras are shown to have an unexpected variety of II$ 1$-factor representations. In addition to developing some general theory we also show that these ideas are related to numerous other problems inoperator algebras.

Semigroups Underlying First-Order Logic

Semigroups Underlying First-Order Logic PDF Author: William Craig
Publisher: American Mathematical Soc.
ISBN: 0821841491
Category : Mathematics
Languages : en
Pages : 298

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Book Description
Boolean, relation-induced, and other operations for dealing with first-order definability Uniform relations between sequences Diagonal relations Uniform diagonal relations and some kinds of bisections or bisectable relations Presentation of ${\mathbf S}_q$, ${\mathbf S}_p$ and related structures Presentation of ${\mathbf S}_{pq}$, ${\mathbf S}_{pe}$ and related structures Appendix. Presentation of ${\mathbf S}_{pqe}$ and related structures Bibliography Index of symbols Index of phrases and subjects List of relations involved in presentations Synopsis of presentations

Entropy and Multivariable Interpolation

Entropy and Multivariable Interpolation PDF Author: Gelu Popescu
Publisher: American Mathematical Soc.
ISBN: 0821839128
Category : Mathematics
Languages : en
Pages : 98

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Book Description
We define a new notion of entropy for operators on Fock spaces and positive multi-Toeplitz kernels on free semigroups. This is studied in connection with factorization theorems for (e.g., multi-Toeplitz, multi-analytic, etc.) operators on Fock spaces. These results lead to entropy inequalities and entropy formulas for positive multi-Toeplitz kernels on free semigroups (resp. multi-analytic operators) and consequences concerning the extreme points of the unit ball of the noncommutative analytic Toeplitz algebra $F ninfty$. We obtain several geometric characterizations of the central intertwining lifting, a maximal principle, and a permanence principle for the noncommutative commutant lifting theorem. Under certain natural conditions, we find explicit forms for the maximal entropy solution of this multivariable commutant lifting theorem. All these results are used to solve maximal entropy interpolation problems in several variables. We obtain explicit forms for the maximal entropy solution (as well as its entropy) of the Sarason, Caratheodory-Schur, and Nevanlinna-Pick type interpolation problems for the noncommutative (resp. commutative) analytic Toeplitz algebra $F ninfty$ (resp. $W ninfty$) and their tensor products with $B({\mathcal H , {\mathcal K )$. In particular, we provide explicit forms for the maximal entropy solutions of several interpolation problems on the unit ball of $\mathbb{C n$.

On Maps from Loop Suspensions to Loop Spaces and the Shuffle Relations on the Cohen Groups

On Maps from Loop Suspensions to Loop Spaces and the Shuffle Relations on the Cohen Groups PDF Author: Jie Wu
Publisher: American Mathematical Soc.
ISBN: 082183875X
Category : Mathematics
Languages : en
Pages : 78

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Book Description
The maps from loop suspensions to loop spaces are investigated using group representations in this article. The shuffle relations on the Cohen groups are given. By using these relations, a universal ring for functorial self maps of double loop spaces of double suspensions is given. Moreover the obstructions to the classical exponent problem in homotopy theory are displayed in the extension groups of the dual of the important symmetric group modules Lie$(n)$, as well as in the top cohomology of the Artin braid groups with coefficients in the top homology of the Artin pure braid groups.

Weil-Petersson Metric on the Universal Teichmuller Space

Weil-Petersson Metric on the Universal Teichmuller Space PDF Author: Leon Armenovich Takhtadzhi︠a︡n
Publisher: American Mathematical Soc.
ISBN: 0821839365
Category : Mathematics
Languages : en
Pages : 136

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Book Description
In this memoir, we prove that the universal Teichmuller space $T(1)$ carries a new structure of a complex Hilbert manifold and show that the connected component of the identity of $T(1)$ -- the Hilbert submanifold $T {0 (1)$ -- is a topological group. We define a Weil-Petersson metric on $T(1)$ by Hilbert space inner products on tangent spaces, compute its Riemann curvature tensor, and show that $T(1)$ is a Kahler-Einstein manifold with negative Ricci and sectional curvatures. We introduce and compute Mumford-Miller-Morita characteristic forms for the vertical tangent bundle of the universal Teichmuller curve fibration over the universal Teichmuller space. As an application, we derive Wolpert curvature formulas for the finite-dimensional Teichmuller spaces from the formulas for the universal Teichmuller space. We study in detail the Hilbert manifold structure on $T {0 (1)$ and characterize points on $T {0 (1)$ in terms of Bers and pre-Bers embeddings by proving that the Grunsky operators $B {1 $ and The results of this memoir were presented in our e-prints: Weil-Petersson metric on the universal Teichmuller space I. Curvature properties and Chern forms, arXiv:math.CV/0312172 (2003), and Weil-Petersson metric on the universal Teichmuller space II. Kahler potential and period mapping, arXiv:math.CV/0406408 (2004).

The Universal Kobayashi-Hitchin Correspondence on Hermitian Manifolds

The Universal Kobayashi-Hitchin Correspondence on Hermitian Manifolds PDF Author: Martin Lübke
Publisher: American Mathematical Soc.
ISBN: 0821839136
Category : Mathematics
Languages : en
Pages : 112

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Book Description
We prove a very general Kobayashi-Hitchin correspondence on arbitrary compact Hermitian manifolds, and we discuss differential geometric properties of the corresponding moduli spaces. This correspondence refers to moduli spaces of ``universal holomorphic oriented pairs''. Most of the classical moduli problems in complex geometry (e. g. holomorphic bundles with reductive structure groups, holomorphic pairs, holomorphic Higgs pairs, Witten triples, arbitrary quiver moduli problems) are special cases of this universal classification problem. Our Kobayashi-Hitchin correspondence relates the complex geometric concept ``polystable oriented holomorphic pair'' to the existence of a reduction solving a generalized Hermitian-Einstein equation. The proof is based on the Uhlenbeck-Yau continuity method. Using ideas from Donaldson theory, we further introduce and investigate canonical Hermitian metrics on such moduli spaces. We discuss in detail remarkable classes of moduli spaces in the non-Kahlerian framework: Oriented holomorphic structures, Quot-spaces, oriented holomorphic pairs and oriented vortices, non-abelian Seiberg-Witten monopoles.

Fredholm Operators and Einstein Metrics on Conformally Compact Manifolds

Fredholm Operators and Einstein Metrics on Conformally Compact Manifolds PDF Author: John M. Lee
Publisher: American Mathematical Soc.
ISBN: 0821839152
Category : Mathematics
Languages : en
Pages : 98

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Book Description
"Volume 183, number 864 (end of volume)."