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Related papers: Equivelar toroids with few flag-orbits

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We describe a class of toric varieties in the $N$-dimensional affine space which are minimally defined by no less than $N-2$ binomial equations.

Algebraic Geometry · Mathematics 2007-05-23 Margherita Barile

We give Leray-Borel-type descriptions for the mod-$2$ and the rational equivariant cohomology rings of the real and the oriented flag manifolds under the canonical torus or 2-torus actions.

Algebraic Topology · Mathematics 2019-01-14 Chen He

We describe a natural geometric relationship between matroids and underlying flag matroids by relating the geometry of the greedy algorithm to monotone path polytopes. This perspective allows us to generalize the construction of underlying…

Combinatorics · Mathematics 2024-06-25 Alexander E. Black , Raman Sanyal

The second part of the paper is devoted to enumeration of $r$-regular toroidal maps up to all homeomorphisms of the torus (unsensed maps). We describe in detail the periodic orientation reversing homeomorphisms of the torus which turn out…

Combinatorics · Mathematics 2017-09-12 Evgeniy Krasko , Alexander Omelchenko

Let G be a compact connected Lie group G and T its maximal torus. The coadjoint orbit O_lambda through lambda in Lie(T)^* is canonically a symplectic manifold. Therefore we can ask the question about its Gromov width. In many known cases…

Symplectic Geometry · Mathematics 2013-03-01 Milena Pabiniak

We compare two formulas for the class of a generic torus orbit closure on the Grassmannian, due to Klyachko and Berget-Fink. The naturally emerging combinatorial objects are semi-standard fillings we call 1-strip-less tableaux.

Combinatorics · Mathematics 2024-01-23 Carl Lian

A quasitoric manifold is a $2n$-dimensional compact smooth manifold with a locally standard action of an $n$-dimensional torus whose orbit space is a simple polytope. In this article, we classify quasitoric manifolds with the second Betti…

Algebraic Topology · Mathematics 2012-09-20 Suyoung Choi , Seonjeong Park , Dong Youp Suh

We describe new arithmetic invariants for pairs of torus orbits on groups isogenous to an inner form of $\mathbf{PGL}_n$ over a number field. These invariants are constructed by studying the double quotient of a linear algebraic group by a…

Number Theory · Mathematics 2019-09-18 Ilya Khayutin

We classify holomorphic as well as algebraic torus equivariant principal $G$-bundles over a nonsingular toric variety $X$, where $G$ is a complex linear algebraic group. It is shown that any such bundle over an affine, nonsingular toric…

Algebraic Geometry · Mathematics 2015-10-15 Indranil Biswas , Arijit Dey , Mainak Poddar

A toric vector bundle $\mathcal{E}$ is a torus equivariant vector bundle on a toric variety. We give a valuation theoretic and tropical point of view on toric vector bundles. We present three (equivalent) classifications of toric vector…

Algebraic Geometry · Mathematics 2023-04-25 Kiumars Kaveh , Christopher Manon

A vertex-transitive map $X$ is a map on a surface on which the automorphism group of $X$ acts transitively on the set of vertices of $X$. If the face-cycles at all the vertices in a map are of same type then the map is called a…

Combinatorics · Mathematics 2021-09-23 Basudeb Datta , Dipendu Maity

In this paper, we study the subvarieties of a complex flag variety that are invariant under the action of a maximal torus. Using combinatorial techniques derived from matroid theory, we introduce a decomposition of this variety into affine,…

One can describe an $n$-dimensional noncommutative torus by means of an antisymmetric $n\times n$-matrix $\theta$. We construct an action of the group $SO(n,n|\bf Z)$ on the space of antisymmetric matrices and show that, generically,…

Quantum Algebra · Mathematics 2007-05-23 Marc Rieffel , Albert Schwarz

We restrict geometric tangential equivariant complex $T^n$-bordism to torus manifolds and provide a complete combinatorial description of the appropriate non-commutative ring. We discover, using equivariant $K$-theory characteristic…

Algebraic Topology · Mathematics 2014-09-10 Alastair Darby

Toric quasifolds are highly singular spaces that were first introduced in order to address, from the symplectic viewpoint, the longstanding open problem of extending the classical constructions of toric geometry to those simple convex…

Symplectic Geometry · Mathematics 2024-04-09 Elisa Prato

We say that a complete nonsingular toric variety (called a toric manifold in this paper) is over $P$ if its quotient by the compact torus is homeomorphic to $P$ as a manifold with corners. Bott manifolds (or Bott towers) are toric manifolds…

Algebraic Topology · Mathematics 2017-05-23 Sho Hasui , Hideya Kuwata , Mikiya Masuda , Seonjeong Park

The K-rings of non-singular complex pro jective varieties as well as quasi- toric manifolds were described in terms of generators and relations in an earlier work of the author with V. Uma. In this paper we obtain a similar description for…

Algebraic Topology · Mathematics 2007-07-12 Parameswaran Sankaran

Inspired by a recent result of Brakensiek et al. that symmetric tensor matroids and rigidity matroids are linked by matroid duality, we define abstract symmetric tensor matroids as a dual concept to abstract rigidity matroids and establish…

Combinatorics · Mathematics 2025-03-20 Bill Jackson , Shin-ichi Tanigawa

Torus orbifolds are topological generalization of symplectic toric orbifolds. We give a construction of smooth orbifolds with torus actions whose boundary is a disjoint union of torus orbifolds using toric topological method. As a result,…

Algebraic Topology · Mathematics 2019-05-21 Soumen Sarkar , Dong Youp Suh

Given integers $n \geq k \geq d$, let $X_{n,k,d}$ be the moduli space of $n$-tuples of lines $(\ell_1, \dots, \ell_n)$ in $\mathbb{C}^k$ such that $\ell_1 + \cdots + \ell_n$ has dimension $d$. We give a quotient presentation of the…

Combinatorics · Mathematics 2024-12-10 Raymond Chou , Tomoo Matsumura , Brendon Rhoades