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The standard P. A. Smith theory of p-group actions on spheres, disks, and euclidean spaces is extended to the case of p-group actions on tori (i.e., products of circles) and coupled with topological surgery theory to give a complete…

Geometric Topology · Mathematics 2007-11-20 Allan L. Edmonds

By an additive action on an algebraic variety $X$ we mean a regular effective action $\mathbb{G}_a^n\times X\to X$ with an open orbit of the commutative unipotent group $\mathbb{G}_a^n$. In this paper, we give a classification of additive…

Algebraic Geometry · Mathematics 2019-08-12 Sergey Dzhunusov

We study holomorphic foliations of aribitrary codimension in smooth complete toric varieties. We show that split foliations are stable if some good behaviour of their singular set is provided. As an application of these results, we exhibit…

Algebraic Geometry · Mathematics 2022-01-25 Sebastián Velazquez

This paper has two main parts. First, we construct certain differential operators, which generalize operators studied by G. Shimura. Then, as an application of some of these differential operators, we construct certain p-adic families of…

Number Theory · Mathematics 2016-08-16 Ellen Eischen

We introduce a simplified (coarse) version of pseudo-differential calculus for operators of order zero on complete Riemannian manifolds. This calculus works for the usual Hormander (1,0) class of operators, as well as for…

Differential Geometry · Mathematics 2025-06-19 Gennadi Kasparov

This paper constructs cospecialization homomorphisms between the (p') versions of the tempered fundamental group of the fibers of a smooth morphism with polystable reduction (the tempered fundamental group is a sort of analog of the…

Algebraic Geometry · Mathematics 2019-02-20 Emmanuel Lepage

Given a finite p-group G acting on a smooth projective curve X over an algebraically closed field k of characteristic p, the dimension of the tangent space of the associated equivariant deformation functor is equal to the dimension of the…

Algebraic Geometry · Mathematics 2011-04-19 Bernhard Köck , Aristides Kontogeorgis

It is known that a finite group G can only act freely on affine n-space if K has positive characteristic p and G is a p-group. In that case the group action is "non-linear" and the ring of regular functions must be a trace-surjective…

Commutative Algebra · Mathematics 2014-03-25 Peter Fleischmann , Christopher Woodcock

We study the equivariant cobordism rings for the action of a torus $T$ on smooth varieties over an algebraically closed field of characteristic zero. We prove a theorem describing the rational $T$-equivariant cobordism rings of smooth…

Algebraic Geometry · Mathematics 2022-11-01 Henry July

We consider deformations of a pair $(X,\partial X)$, where $X$ is an affine toric Gorenstein variety and $\partial X$ is its boundary. We compute the tangent and obstruction space for the corresponding deformation functor and for an…

Algebraic Geometry · Mathematics 2025-09-16 Matej Filip

We construct a differential graded Lie algebra $\fg$ controlling the Poisson deformations of an affine Poisson variety. We analyse $\fg$ in the case of affine Gorenstein toric Poisson varieties. Moreover, explicit description of the second…

Algebraic Geometry · Mathematics 2018-12-13 Matej Filip

We construct Fourier transforms relating functions and distributions on finite height $p$-divisible rigid analytic groups and objects in a dual category of $\mathbb{Z}_p$-local systems with analyticity conditions. Our Fourier transforms are…

Number Theory · Mathematics 2025-07-09 Andrew Graham , Pol van Hoften , Sean Howe

We introduce and develop the theory of Newton nondegenerate local Weil divisors $(X,0)$ in toric affine varieties. We characterize in terms of the toric combinatorics of the Newton diagram different properties of such singular germs:…

Algebraic Geometry · Mathematics 2021-02-08 András Némethi , Baldur Sigurðsson

Let $D$ be a reduced divisor in $\mathbb P^n_k$ for an algebraically closed field $k$ of positive characteristic $p > 0$. We prove that if $(\mathbb P^n_k, D)$ is Frobenius liftable modulo $p^2$, then $D$ is a toric divisor. As a corollary,…

Algebraic Geometry · Mathematics 2025-07-17 Tatsuro Kawakami , Supravat Sarkar , Jakub Witaszek

In "Frobenius Categories versus Brauer Blocks", Progress in Math. 274, we introduce the Frobenius P-categories giving two quite different definitions of them. In this paper, we exhibit a third equivalent definition based on the form of the…

Group Theory · Mathematics 2010-04-12 Lluis Puig

A polynomial assignment for a continuous action of a compact torus $T$ on a topological space $X$ assigns to each $p\in X$ a polynomial function on the Lie algebra of the isotropy group at $p$ in such a way that a certain compatibility…

Algebraic Topology · Mathematics 2018-03-16 Oliver Goertsches , Augustin-Liviu Mare

Let X be a normal affine T-variety, where T stands for the algebraic torus. We classify Ga-actions on X arising from homogeneous locally nilpotent derivations of fiber type. We deduce that any variety with trivial Makar-Limanov (ML)…

Algebraic Geometry · Mathematics 2011-02-08 Alvaro Liendo

Let $\mathcal A$ be a Hom-finite abelian category with enough projectives. In this note, we show that any covariantly finite $\tau$-rigid subcategory is contained in a support $\tau$-tilting subcategory. We also show that support…

Representation Theory · Mathematics 2023-02-07 Yu Liu , Panyue Zhou

Let X be a complete toric variety with homogeneous coordinate ring S. In this article, we compute upper and lower bounds for the codimension in the critical degree of ideals of S generated by dim(X)+1 homogeneous polynomials that don't…

Algebraic Geometry · Mathematics 2007-05-23 David Cox , Alicia Dickenstein

We introduce a division formula on a possibly singular projective subvariety $X$ of complex projective space $\Pk^N$, which, e.g., provides explicit representations of solutions to various polynomial division problems on the affine part of…

Complex Variables · Mathematics 2016-03-16 Mats Andersson , Lisa Nilsson