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Related papers: A note on Lefschetz spheres and their relatives

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We construct examples of embedded flexible cross-polytopes in the spheres of all dimensions. These examples are interesting from two points of view. First, in dimensions 4 and higher, they are the first examples of embedded flexible…

Metric Geometry · Mathematics 2024-11-20 Alexander A. Gaifullin

This article concludes the comprehensive study started in [Sz5], where the first non-trivial isospectral pairs of metrics are constructed on balls and spheres. These investigations incorporate 4 different cases since these balls and spheres…

Differential Geometry · Mathematics 2007-05-23 Z. I. Szabo

Decomposition classes provide a way of partitioning the Lie algebras of an algebraic group into equivalence classes based on the Jordan decomposition. In this paper, we investigate the decomposition classes of the Lie algebras of connected…

Representation Theory · Mathematics 2025-11-04 Joel Summerfield

The aim of this paper is to get some results about ruled surfaces which configure a projective theory of scrolls and ruled surfaces. Our ideas follow the viewpoint of Corrado Segre, but we employ the contemporaneous language of locally free…

Algebraic Geometry · Mathematics 2007-05-23 Luis Fuentes Garcia , Manuel Pedreira Perez

Motivated by the relationship between numerical Grothendieck groups induced by the embedding of a smooth anticanonical elliptic curve into a del Pezzo surface, we define the notion of a quasi del Pezzo homomorphism between pseudolattices…

Algebraic Geometry · Mathematics 2020-01-06 Andrew Harder , Alan Thompson

In the present paper Mori extremal rays of a smooth projective manifold X are divided into two classes: L-supported and L-negligible (where ``L'' stands for ``Lefschetz'' since the division comes from Hard Lefschetz Theorem). Roughly…

Algebraic Geometry · Mathematics 2007-05-23 Jaroslaw A. Wisniewski

This thesis focuses on algebraic shifting and its applications to f-vector theory of simplicial complexes and more general graded posets. In particular, several approaches and partial results concerning the g-conjecture for simplicial…

Combinatorics · Mathematics 2007-09-21 Eran Nevo

In this article we describe indecomposable objects of the derived categories of a branch class of associative algebras. To this class belong such known classes of algebras as gentle algebras, skew-gentle algebras and certain degenerations…

Representation Theory · Mathematics 2016-09-07 Igor Burban , Yuriy Drozd

We introduce invariants of Hurwitz equivalence classes with respect to arbitrary group $G$. The invariants are constructed from any right $G$-modules $M$ and any $G$-invariant bilinear function on $M$, and are of bilinear forms. For…

Geometric Topology · Mathematics 2017-02-02 Takefumi Nosaka

Collino \cite{colo} discovered indecomposable motivic cycles in the group $H^{2g-1}_{\mathcal M}(J(C),{\mathds Z}(g))$. In an earlier paper we described the construction of some new motivic cycles which can be viewed as a generalization of…

Algebraic Geometry · Mathematics 2023-04-20 Ramesh Sreekantan

The convex feasibility problem consists in finding a point in the intersection of a finite family of closed convex sets. When the intersection is empty, a best compromise is to search for a point that minimizes the sum of the squared…

Optimization and Control · Mathematics 2018-05-08 Roberto Cominetti , Vera Roshchina , Andrew Williamson

We use the integral by parts to get a Liouville type theorem for a class quasilinear $p$-Laplace type equation on the sphere, this $p$-Laplace type equation arises from the study of asymptotic behavior near the origin for the semi-linear…

Analysis of PDEs · Mathematics 2022-11-08 Daowen Lin , Xi-Nan Ma

We show the existence of a family of nontrivial smooth contractible domains on the sphere that admit Neumann eigenfunctions of the Laplacian which are constant on the boundary. These domains are contained on the half-sphere, in stark…

Analysis of PDEs · Mathematics 2025-10-08 Gonzalo Cao-Labora , Antonio J. Fernández

Geometric vertex decomposition and liaison are two frameworks that have been used to produce similar results about similar families of algebraic varieties. In this paper, we establish an explicit connection between these approaches. In…

Commutative Algebra · Mathematics 2023-06-22 Patricia Klein , Jenna Rajchgot

In [1309.1899], Ranestad and Voisin showed, quite surprisingly, that the divisor in the moduli space of cubic fourfolds consisting of cubics "apolar to a Veronese surface" is not a Noether-Lefschetz divisor. We give an independent proof of…

Algebraic Geometry · Mathematics 2018-11-06 Nicolas Addington , Asher Auel

This is a case study of the algebraic boundary of convex hulls of varieties. We focus on surfaces in fourspace to showcase new geometric phenomena that neither curves nor hypersurfaces do. Our method is a detailed analysis of a general…

Algebraic Geometry · Mathematics 2025-06-02 Chiara Meroni , Kristian Ranestad , Rainer Sinn

Motivated by recent studies of superconformal mechanics extended by spin degrees of freedom, we construct minimally superintegrable models of spinning particles on 2-sphere, the spin degrees of freedom of which are represented by a 3-vector…

High Energy Physics - Theory · Physics 2021-03-17 Anton Galajinsky

In this note we extend Voevodsky's nilpotence conjecture from smooth projective schemes to the broader setting of smooth proper dg categories. Making use of this noncommutative generalization, we then address Voevodsky's original conjecture…

Algebraic Geometry · Mathematics 2014-11-05 Marcello Bernardara , Matilde Marcolli , Goncalo Tabuada

The theory of surfaces in Euclidean space can be naturally formulated in the more general context of Legendre surfaces into the space of contact elements. We address the question of deformability of Legendre surfaces with respect to the…

Differential Geometry · Mathematics 2007-12-06 Emilio Musso , Lorenzo Nicolodi

In 2005, building on his own recent work and that of F. Zanello, A. Iarrobino discovered some constructions that, he conjectured, would yield level algebras with non-unimodal Hilbert functions. This thesis provides proofs of non-unimodality…

Commutative Algebra · Mathematics 2007-08-27 Arthur Jay Weiss