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Related papers: Wedge operations and torus symmetries II

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Let $P_m(J)$ denote a simplicial complex obtainable from consecutive wedge operations from an $m$-gon. In this paper, we completely classify toric manifolds over $P_m(J)$ and prove that all of them are projective. As a consequence, we…

Algebraic Geometry · Mathematics 2017-05-02 Suyoung Choi , Hanchul Park

We study toric varieties over an arbitrary field with an emphasis on toric surfaces in the Merkurjev-Panin motivic category of "K-motives". We explore the decomposition of certain toric varieties as K-motives into products of central simple…

Algebraic Geometry · Mathematics 2018-09-14 Fei Xie

Given a $G$-toric, folded-symplectic manifold with co-orientable folding hypersurface, we show that its orbit space is naturally a manifold with corners $W$ equipped with a smooth map $\psi: W \to \frak{g}^*$, where $\frak{g}^*$ is the dual…

Symplectic Geometry · Mathematics 2015-11-26 Daniel Hockensmith

In a toric symplectic manifold, regular fibres of the moment map are Lagrangian tori which are called toric fibres. We discuss the question which two toric fibres are equivalent up to a Hamiltonian diffeomorphism of the ambient space. On…

Symplectic Geometry · Mathematics 2025-07-02 Joé Brendel

We show that, for a complete simplicial toric variety $X$, we can determine its homotopy $\KH$-theory entirely in terms of the torus pieces of open sets forming an open cover of $X$. We then construct conditions under which, given two…

K-Theory and Homology · Mathematics 2013-03-12 Adam Massey

Let $K/k$ be a finite Galois extension, $G=\text{Gal}(K/k)$, $\Sigma$ be a fan in a lattice $N$ and $X_{\Sigma}$ be an associated toric variety over $k$. It is well known that the set of $K/k$-forms of $X_{\Sigma}$ is in bijection with…

Algebraic Geometry · Mathematics 2018-04-27 Seungkyun Park

Let $K$ be an $(n-1)$-dimensional piecewise linear sphere on $[m]$, where $m\leq n+4$. There are a canonical action of $m$-dimensional torus $T^m$ on the moment-angle complex $\mathcal{Z}_K$, and a canonical action of $\mathbb{Z}_2^m$ on…

Algebraic Topology · Mathematics 2025-12-19 Suyoung Choi , Hyeontae Jang , Mathieu Vallée

We consider the set of forms of a toric variety over an arbitrary field: those varieties which become isomorphic to a toric variety after base field extension. In contrast to most previous work, we also consider arbitrary isomorphisms…

Algebraic Geometry · Mathematics 2016-10-04 Alexander Duncan

For an action of a compact torus $T$ on a smooth compact manifold~$X$ with isolated fixed points the number $\frac{1}{2}\dim X-\dim T$ is called the complexity of the action. In this paper we study certain examples of torus actions of…

Algebraic Topology · Mathematics 2023-02-20 Anton Ayzenberg

Toric topology emerged in the end of the 1990s on the borders of equivariant topology, algebraic and symplectic geometry, combinatorics and commutative algebra. It has quickly grown up into a very active area with many interdisciplinary…

Algebraic Topology · Mathematics 2015-06-09 Victor Buchstaber , Taras Panov

The paper surveys some new results and open problems connected with such fundamental combinatorial concepts as polytopes, simplicial complexes, cubical complexes, and subspace arrangements. Particular attention is paid to the case of…

Algebraic Topology · Mathematics 2007-05-23 Victor M. Buchstaber , Taras E. Panov

A small cover is a closed smooth manifold of dimension $n$ having a locally standard $\mathbb{Z}_2^n$-action whose orbit space is isomorphic to a simple polytope. A typical example of small covers is a real projective toric manifold (or,…

Algebraic Topology · Mathematics 2017-03-16 Suyoung Choi , Hanchul Park

We consider an effective action of a compact (n-1)-torus on a smooth 2n-manifold with isolated fixed points. We prove that under certain conditions the orbit space is a closed topological manifold. In particular, this holds for certain…

Algebraic Topology · Mathematics 2019-03-11 Anton Ayzenberg

Given a hypersurface in a complex projective space, we prove that the multidegrees of its toric polar map agree, up to sign, with the coefficients of the Chern-Schwartz-MacPherson class of a distinguished open set, namely the complement of…

Algebraic Geometry · Mathematics 2023-05-03 Thiago Fassarella , Nivaldo Medeiros , Rodrigo Salomão

A theory of characteristic classes of vector bundles and smooth manifolds plays an important role in the theory of smooth manifolds. An investigation of reasonable notions of characteristic classes of singular spaces started since a…

Algebraic Geometry · Mathematics 2007-05-23 Joerg Schuermann , Shoji Yokura

Let a $k$-dimensional torus $T^k$ act on a $2n$-dimensional compact connected almost complex manifold $M$ with isolated fixed points. As for circle actions, we show that there exists a (directed labeled) multigraph that encodes weights at…

Differential Geometry · Mathematics 2022-02-23 Donghoon Jang

We construct all possible Hamiltonian torus actions for which all the non-empty reduced spaces are two dimensional (and not single points) and the manifold is connected and compact, or, more generally, the moment map is proper as a map to a…

Symplectic Geometry · Mathematics 2014-11-11 Yael Karshon , Susan Tolman

In this paper, we give a method to describe the numerical class of a torus invariant surface on a projective toric manifold. As applications, we can classify toric 2-Fano manifolds of Picard number 2 or of dimension at most 4.

Algebraic Geometry · Mathematics 2011-06-30 Hiroshi Sato

In this paper we compute the motivic Chern classes and homology Hirzebruch characteristic classes of (possibly singular) toric varieties, which in the complete case fit nicely with a generalized Hirzebruch-Riemann-Roch theorem. As special…

Algebraic Geometry · Mathematics 2016-05-24 Laurentiu Maxim , Joerg Schuermann

This survey may be seen as an introduction to the use of toric and tropical geometry in the analysis of plane curve singularities, which are germs $(C,o)$ of complex analytic curves contained in a smooth complex analytic surface $S$. The…

Algebraic Geometry · Mathematics 2022-07-28 Evelia R. García Barroso , Pedro D. González Pérez , Patrick Popescu-Pampu