English
Related papers

Related papers: Equivariant geometry of low-dimensional quadrics

200 papers

We construct normal forms for Levi degenerate hypersurfaces of finite type in $\mathbb C^2$. As one consequence, an explicit solution to the problem of local biholomorphic equivalence is obtained. Another consequence determines the…

Complex Variables · Mathematics 2007-05-23 Martin Kolar

Characterizations of all continuous, additive and $\mathrm{GL}(n)$-equivariant endomorphisms of the space of convex functions on a Euclidean space $\mathbb{R}^n$, of the subspace of convex functions that are finite in a neighborhood of the…

Metric Geometry · Mathematics 2023-03-29 Georg C. Hofstätter , Jonas Knoerr

We develop an equivariant version of Seiberg-Witten-Floer cohomology for finite group actions on rational homology $3$-spheres. Our construction is based on an equivariant version of the Seiberg-Witten-Floer stable homotopy type, as…

Geometric Topology · Mathematics 2024-03-27 David Baraglia , Pedram Hekmati

We study the most elementary aspects of harmonic analysis on a homogeneous space of a deformation of the two-dimensional Euclidean group, admitting generalizations to dimensions three and four, whose quantum parameter has the physical…

q-alg · Mathematics 2008-02-03 F. Bonechi , R. Giachetti , M. A. del Olmo , E. Sorace , M. Tarlini

We classify the possible behaviour of Poincar\'e-Dulac normal forms for dynamical systems in $R^n$ with nonvanishing linear part and which are equivariant under (the fundamental representation of) all the simple compact Lie algebras and…

Mathematical Physics · Physics 2009-11-07 Giuseppe Gaeta

In this work the equivariant signature of a manifold with proper action of a discrete group is defined as an invariant of equivariant bordisms. It is shown that the computation of this signature can be reduced to its computation on fixed…

Algebraic Topology · Mathematics 2011-12-12 A. S. Mishchenko , Quitzeh Morales Meléndez

In this paper we discuss various aspects of the problem of determining the minimal dimension of an injective linear representation of a finite semigroup over a field. We outline some general techniques and results, and apply them to…

Group Theory · Mathematics 2012-07-27 Volodymyr Mazorchuk , Benjamin Steinberg

All finite sets of equiangular lines spanning finite-dimensional unitary spaces are determined for which the action on the lines of the set-stabilizer in the unitary group is 2-transitive with a regular normal subgroup.

Metric Geometry · Mathematics 2022-04-05 Ulrich Dempwolff , William M. Kantor

In this paper, we examine Lie group actions on moduli spaces (sets themselves built as quotients by group actions) and their fixed points. We show that when the Lie group is compact and connected, we obtain a linear constraint. This…

Representation Theory · Mathematics 2025-01-15 C. J. Lang

We show that Euclidean geometry in suitably high dimension can be expressed as a theory of orthogonality of subspaces with fixed dimensions and fixed dimension of their meet.

Metric Geometry · Mathematics 2012-03-14 J. Konarzewski , M. Żynel

We construct an equivariant microlocal lift for locally symmetric spaces. In other words, we demonstrate how to lift, in a ``semi-canonical'' fashion, limits of eigenfunction measures on locally symmetric spaces to Cartan-invariant measures…

Representation Theory · Mathematics 2013-07-25 Lior Silberman , Akshay Venkatesh

We study linearization models for continuous one-parameter semigroups of parabolic type. In particular, we introduce new limit schemes to obtain solutions of Abel's functional equation and to study asymptotic behavior of such semigroups.…

Complex Variables · Mathematics 2009-07-16 Mark Elin , Dmitry Khavinson , Simeon Reich , David Shoikhet

We consider the following problem: for which classes of finite groups, and in particular finite simple groups, does the minimal dimension of a faithful, smooth action on a homology sphere coincide with the minimal dimension of a faithful,…

Geometric Topology · Mathematics 2010-09-06 Bruno P. Zimmermann

We consider periodic and quasi-periodic solutions of the three-body problem with homogeneous potential from the point of view of the equivariant calculus of variations. First, we show that symmetry groups of the Lagrangian action functional…

Dynamical Systems · Mathematics 2008-06-11 Vivina Barutello , Davide L. Ferrario , Susanna Terracini

The main result of this paper is a construction of fundamental domains for certain group actions on Lorentz manifolds of constant curvature. We consider the simply connected Lie group G~, the universal cover of the group SU(1,1) of…

Differential Geometry · Mathematics 2013-04-12 Anna Pratoussevitch

The main result of this article is to construct infinite families of non-equivalent equivariant real forms of linear C*-actions on affine four-space. We consider the real form of C* whose fixed point is a circle. In [F-MJ] one example of a…

Algebraic Geometry · Mathematics 2018-07-03 Lucy Moser-Jauslin

We construct a series of homogeneous spaces G/H of reductive type which admit proper actions of discrete subgroups of G isomorphic to cocompact lattices of O(n,1) (n=2,3,4) but do not admit proper actions of non-compact semisimple subgroups…

Group Theory · Mathematics 2025-06-04 Maciej Bochenski , Yosuke Morita

Let G be a compact Lie-group, X a compact G-CW-complex. We define equivariant geometric K-homology groups K^G_*(X), using an obvious equivariant version of the (M,E,f)-picture of Baum-Douglas for K-homology. We define explicit natural…

K-Theory and Homology · Mathematics 2012-10-12 Paul Baum , Herve Oyono-Oyono , Thomas Schick , Michael Walter

We use the theory of cubic structures to give a fixed point Riemann-Roch formula for the equivariant Euler characteristics of coherent sheaves on projective flat schemes over Z with a tame action of a finite abelian group. This formula…

Number Theory · Mathematics 2007-05-23 T. Chinburg , G. Pappas , M. Taylor

In these notes we present a corrected version of the algorithm for abelianization of stabilizers of finite group actions on smooth manifolds using equivariant blow ups.

Algebraic Geometry · Mathematics 2007-05-23 Victor V. Batyrev