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Related papers: Some Hermitian K-groups via geometric topology

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In this paper we discuss the topology of the symplectomorphism group of a product of two 2-dimensional spheres when the ratio of their areas lies in the interval (1,2]. More precisely we compute the homotopy type of this symplectomorphism…

Symplectic Geometry · Mathematics 2014-11-11 Silvia Anjos

We consider groups G which have a cocompact, 3-manifold model for the classifying space \underline{E}G. We provide an algorithm for computing the rationalized equivariant K-homology of \underline{E}G. Under the additional hypothesis that…

K-Theory and Homology · Mathematics 2013-04-30 Jean-François Lafont , Ivonne J. Ortiz , Rubén J. Sánchez-García

For a finite volume geodesic polyhedron P in hyperbolic 3-space, with the property that all interior angles between incident faces are integral submultiples of Pi, there is a naturally associated Coxeter group generated by reflections in…

K-Theory and Homology · Mathematics 2017-05-24 J. -F. Lafont , B. A. Magurn , I. J. Ortiz

A spectral sequence calculating the homology groups of some spaces of maps equivariant under compact group actions is described. For the main example, we calculate the rational homology groups of spaces of even and odd maps $S^m \to S^M$,…

Algebraic Topology · Mathematics 2021-07-01 Victor Vassiliev

We propose new tools based on basic lattice theory to calculate the integral cohomology of the quotient of a manifold by an automorphism group of prime order. As examples of applications, we provide the Beauville--Bogomolov forms of some…

Algebraic Geometry · Mathematics 2019-09-06 Grégoire Menet

Properties of Hermitian forms are used to investigate several natural questions from CR Geometry. To each Hermitian symmetric polynomial we assign a Hermitian form. We study how the signature pairs of two Hermitian forms behave under the…

Complex Variables · Mathematics 2011-10-20 John P. D'Angelo , Jiri Lebl

We present the concept of the topological symmetry group as a way to analyze the symmetries of non-rigid molecules. Then we characterize all of the groups which can occur as the topological symmetry group of an embedding of the complete…

Geometric Topology · Mathematics 2015-03-13 Dwayne Chambers , Erica Flapan , John D. O'Brien

Consider a pair of symplectic varieties dual with respect to 3D-mirror symmetry. The K-theoretic limit of the elliptic duality interface is an equivariant K-theory class of the product. We show that this class provides correspondences in…

Algebraic Geometry · Mathematics 2020-08-17 Yakov Kononov , Andrey Smirnov

Bivariant (equivariant) K-theory is the standard setting for non-commutative topology. We may carry over various techniques from homotopy theory and homological algebra to this setting. Here we do this for some basic notions from…

K-Theory and Homology · Mathematics 2015-10-23 Ralf Meyer , Ryszard Nest

We prove that the homology groups of a principal ample groupoid vanish in dimensions greater than the dynamic asymptotic dimension of the groupoid (as a side-effect of our methods, we also give a new model of groupoid homology in terms of…

Operator Algebras · Mathematics 2023-12-06 Christian Bönicke , Clément Dell'Aiera , James Gabe , Rufus Willett

This research notes is intended to provide a quick introduction to the subject. We expose a K-theoretic approach to study group C*-algebras: started in the elementary part, with one example of description of the structure of C*-algebras of…

K-Theory and Homology · Mathematics 2014-06-09 Do Ngoc Diep

The main purpose of this paper is to give a topological and symplectic classification of completely integrable Hamiltonian systems in terms of characteristic classes and other local and global invariants.

Differential Geometry · Mathematics 2007-05-23 Nguyen Tien Zung

In this paper we introduce two new methods for constructing harmonic morphisms from solvable Lie groups. The first method yields global solutions from any simply connected nilpotent Lie group and from any Riemannian symmetric space of…

Differential Geometry · Mathematics 2007-09-05 Sigmundur Gudmundsson , Martin Svensson

Let $A$ be a Cartan matrix and $G(A)$ be the Kac-Moody group associated to Cartan matrix $A$. In this paper, we discuss the computation of the rank $i_k$ of homotopy group $\pi_k(G(A))$. For a large class of Kac-Moody groups, we construct…

Algebraic Topology · Mathematics 2015-01-20 Zhao Xu-an , Jin Chunhua

The goal of this paper is to demonstrate the use of techniques from hyperbolic geometry to compute generating sets of certain subgroups of $SL^+(2,\mathbb{C})$; specifically, $SO^+(Q,\mathbb{Z})$ for $Q$ some integral quadratic form of…

Numerical Analysis · Mathematics 2008-06-05 Gregory Muller

We provide a new branching rule from the general linear group $GL_{2n}(\mathbb{C})$ to the symplectic group $Sp_{2n}(\mathbb{C})$ by establishing a simple algorithm which gives rise to a bijection from the set of semistandard tableaux of a…

Representation Theory · Mathematics 2025-05-14 Hideya Watanabe

Using algebraic and topological K-theory together with complex C^*-algebras, we prove that every abelian group may be realized as the centre of a strongly torsion generated group whose integral homology is zero in dimension one and…

Group Theory · Mathematics 2016-07-06 A. J. Berrick , M. Matthey

The article [14] gives a list of 51 symplectic hypergeometric monodromy groups corresponding to primitive pairs of degree four polynomials, which are products of cyclotomic polynomials, and for which, the absolute value of the leading…

Group Theory · Mathematics 2016-10-19 Sandip Singh

A geometric algorithm is introduced for finding a symplectic basis of the first integral homology group of a compact Riemann surface, which is a $p$-cyclic covering of ${\mathbb C} P^1$ branched over 3 points. The algorithm yields a…

Algebraic Geometry · Mathematics 2014-12-12 Yuuki Tadokoro

The 2-primary torsion of the higher algebraic K-theory of the integers has been computed by Rognes and Weibel. In this paper we prove analogous results for the Hermitian K-theory of the integers with 2 inverted (denoted by Z'). We also…

K-Theory and Homology · Mathematics 2007-05-23 A. J. Berrick , M. Karoubi