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Related papers: Remarks on totally positive flag manifolds

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The totally nonnegative part of a partial flag variety G/P is known to have a decomposition into semi-algebraic cells. We show that the closure of a cell is again a union of cells and give a combinatorial description of the closure…

Algebraic Geometry · Mathematics 2007-05-23 Konstanze Rietsch

We study the antipodal subsets of the full flag manifolds $\mathcal{F}(\mathbb{R}^d)$. As a consequence, for natural numbers $d \ge 2$ such that $d\ne 5$ and $d \not\equiv 0,\pm1 \mod 8$, we show that Borel Anosov subgroups of ${\rm…

Geometric Topology · Mathematics 2025-01-08 Subhadip Dey

This paper is concerned with the study of spaces of naturally defined cycles associated to SL(n,R)-flag domains. These are compact complex submanifolds in open orbits of real semisimple Lie groups in flag domains of their complexification.…

Algebraic Geometry · Mathematics 2014-09-23 Ana-Maria Brecan

We classify completely the intersections of the Hermitian curve with parabolas in the affine plane. To obtain our results we employ well-known algebraic methods for finite fields and geometric properties of the curve automorphisms. In…

Commutative Algebra · Mathematics 2016-04-01 Chiara Marcolla , Marco Pellegrini , Massimiliano Sala

For some partial flag manifolds of semisimple real Lie groups, including many full flag manifolds, transverse circles are known to be locally maximally transverse. We complete the classification of all partial flag manifolds of split real…

Geometric Topology · Mathematics 2025-07-28 Parker Evans , J. Maxwell Riestenberg

We study the isotropy representation of real flag manifolds associated to simple Lie algebras that are split real forms of complex simple Lie algebras. For each Dynkin diagram the invariant irreducible subspaces for the compact part of the…

Differential Geometry · Mathematics 2014-05-27 Mauro Patrão , Luiz A. B. San Martin

The paper concerns the topology of an isospectral real smooth manifold for certain Jacobi element associated with real split semisimple Lie algebra. The manifold is identified as a compact, connected completion of the disconnected Cartan…

Symplectic Geometry · Mathematics 2007-05-23 L. Casian , Y. Kodama

We begin the study of completeness of affine connections, especially those on statistical manifolds as well as on affine hypersurfaces. We collect basic facts, prove new theorems and provide examples with remarkable properties.

Differential Geometry · Mathematics 2020-03-27 Barbara Opozda

We determine the structure of the finite groups with the property that every cyclic subgroup is the intersection of maximal subgroups, comparing this property with the one where all proper subgroups are intersections of maximal subgroups.

Group Theory · Mathematics 2025-08-07 Andrea Lucchini

We prove that any coadjoint orbit with real eigenvalues of a complex semisimple Lie group, equipped with the real part of the canonical holomorphic symplectic form, is symplectomorphic to the cotangent bundle of a (partial) flag manifold.…

Symplectic Geometry · Mathematics 2008-10-22 Hassan Azad , Erik van den Ban , Indranil Biswas

We introduce the separating semigroup of a real algebraic curve of dividing type. The elements of this semigroup record the possible degrees of the covering maps obtained by restricting separating morphisms to the real part of the curve. We…

Algebraic Geometry · Mathematics 2020-08-04 Mario Kummer , Kristin Shaw

We give a positive answer to the Huneke-Wiegand Conjecture for monomial ideals over free numerical semigroup rings, and for two generated monomial ideals over complete intersection numerical semigroup rings.

Commutative Algebra · Mathematics 2012-11-20 Pedro A. Garcia-Sanchez , Micah J. Leamer

We study isometric Lie group actions on symmetric spaces admitting a section, i.e. a submanifold which meets all orbits orthogonally at every intersection point. We classify such actions on the compact symmetric spaces with simple isometry…

Differential Geometry · Mathematics 2011-01-12 Andreas Kollross

We classify the (semi-simple parts of the) Lie algebra of the Zariski closure of a discrete subgroup of a split simple real-algebraic Lie group, whose limit sets are minimal and such that the limit set in the space of full flags contains a…

Representation Theory · Mathematics 2023-08-22 Andrés Sambarino

In this paper, we present a closed, computable formula for the cellular homology coefficients of real flag manifolds associated with split real forms of type A. We demonstrate the process using movements within the code diagram for…

Algebraic Topology · Mathematics 2024-10-10 Jordan Lambert , Lonardo Rabelo

Motivated by intuitive properties of physical quantities, the notion of a non-anomalous semigroup is formulated. These are totally ordered semigroups where there are no `infinitesimally close' elements. The real numbers are then defined as…

History and Overview · Mathematics 2016-07-21 Damon Binder

We survey recent work on the geometry and dynamics of transverse subgroups of semi-simple Lie groups.

Dynamical Systems · Mathematics 2025-02-12 Richard Canary , Tengren Zhang , Andrew Zimmer

We propose a subconjecture that implies the semiampleness conjecture for quasi-numerically positive log canonical divisors and prove the semiampleness in some elementary cases.

Algebraic Geometry · Mathematics 2015-11-11 Shigetaka Fukuda

We investigate whether the group algebra of a finite group over a localisation of the integers is semiperfect. The main result is a necessary and sufficient arithmetic criterion in the ordinary case. In the modular case, we propose a…

Rings and Algebras · Mathematics 2025-10-10 Dylan Johnston , Dmitriy Rumynin

We determine the structure of the semisimple group algebra of certain groups over the rationals and over those finite fields where the Wedderburn decompositions have the least number of simple components. We apply our work to obtain similar…

Representation Theory · Mathematics 2010-09-06 Raul A. Ferraz , Edgar G. Goodaire , Cesar Polcino Milies