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Related papers: Unlikely Intersections with Bruhat Strata

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Consider all moduli points corresponding with polarized abelian varieties in characteristic p such that the associated quasi-polarized p-divisible group is geometrically isomorphic with a given one. This defines a subset C of the moduli…

Algebraic Geometry · Mathematics 2007-05-23 Frans Oort

In this work, we identify a certain family of higher-dimensional formal groups over the ring of $p$-adic integers such that any two formal groups in that class coincide if they share infinitely many torsion points. As a useful application,…

Number Theory · Mathematics 2025-01-20 Mabud Ali Sarkar , Absos Ali Shaikh

We extend the relative theory of admissible pairs and $p$-adic Hodge structures introduced in Part II to allow variation in the underlying local systems of $\mathbb{Q}_p$-vector spaces and isocrystals. This extension accommodates, in…

Number Theory · Mathematics 2026-03-25 Sean Howe , Christian Klevdal

Let $G$ be a connected semi-simple algebraic group of adjoint type over an algebraically closed field, and let $\overline{G}$ be the wonderful compactification of $G$. For a fixed pair $(B, B^-)$ of opposite Borel subgroups of $G$, we look…

Representation Theory · Mathematics 2009-07-08 Xuhua He , Jiang-Hua Lu

In this paper, we study the basic locus in the fiber at $p$ of a certain unitary Shimura variety with a certain parahoric level structure. The basic locus $\widehat{\mathcal{M}^{ss}}$ is uniformized by a formal scheme $\mathcal{N}$ which is…

Number Theory · Mathematics 2018-07-27 Sungyoon Cho

Real Bruhat cells give an important and well studied stratification of such spaces as $GL_{n+1}$, $Flag_{n+1} = SL_{n+1}/B$, $SO_{n+1}$ and $Spin_{n+1}$. We study the intersections of a top dimensional cell with another cell (for another…

Algebraic Topology · Mathematics 2022-01-19 Emília Alves , Nicolau C. Saldanha

We investigate the viability of defining an intersection product on algebraic cycles on a singular algebraic variety by pushing forward intersection products formed on a resolution of singularities. For varieties with resolutions having a…

Algebraic Geometry · Mathematics 2014-04-09 Joseph Ross

In this paper we study the Bruhat decomposition of not necessarily connected reductive quasi-split groups $G$ with respect to not necessarily connected parabolic subgroups. If $G$ is defined over a finite field, we construct a smooth…

Algebraic Geometry · Mathematics 2013-12-25 Torsten Wedhorn

We define a variant of intersection space theory that applies to many compact complex and real analytic spaces $X$, including all complex projective varieties; this is a significant extension to a theory which has so far only been shown to…

Algebraic Topology · Mathematics 2018-12-06 Christian Geske

We describe the structure of the supersingular locus of a Shimura variety for a quaternionic unitary similitude group of degree $2$ over a ramified odd prime $p$ if the level at $p$ is given by a special maximal compact open subgroup. More…

Number Theory · Mathematics 2021-05-14 Yasuhiro Oki

We prove a general likely intersections theorem, a counterpart to the Zilber-Pink conjectures, under the assumption that the Ax-Schanuel property and some mild additional conditions are known to hold for a given category of complex quotient…

Algebraic Geometry · Mathematics 2026-01-14 Sebastian Eterović , Thomas Scanlon

In this paper, we prove an intersection-theoretic result pertaining to curves in certain Hilbert modular surfaces in positive characteristic. Specifically, we show that given two appropriate curves C,D parameterizing abelian surfaces with…

Algebraic Geometry · Mathematics 2025-03-07 Asvin G. , Qiao He , Ananth N. Shankar

In [GTZ08, GTZ12], the following result was established: given polynomials $f,g\in\mathbb{C}[x]$ of degrees larger than $1$, if there exist $\alpha,\beta\in\mathbb{C}$ such that their corresponding orbits $\mathcal{O}_f(\alpha)$ and…

Number Theory · Mathematics 2024-08-14 Simone Coccia , Dragos Ghioca , Jungin Lee , Gyeonghyeon Nam

Let $G$ be a semiabelian variety defined over an algebraically closed field $K$ of prime characteristic. We describe the intersection of a subvariety $X$ of $G$ with a finitely generated subgroup of $G(K)$.

Number Theory · Mathematics 2023-06-07 Dragos Ghioca , She Yang

Exceptional points play a pivotal role in the topology of non-Hermitian systems, and significant advances have been made in classifying exceptional points and exploring the associated phenomena. Exceptional surfaces, which are hypersurfaces…

Materials Science · Physics 2022-09-08 Hongwei Jia , Ruo-Yang Zhang , Jing Hu , Yixin Xiao , Yifei Zhu , C. T. Chan

For a split reductive group G over a finite field, we show that the intersection (cohomology) motive of the moduli stack of iterated G-shtukas with bounded modification and level structure is defined independently of the standard…

Algebraic Geometry · Mathematics 2020-02-19 Timo Richarz , Jakob Scholbach

In this paper we study the supersingular locus of the reduction modulo p of the Shimura variety for GU(1,s) in the case of an inert prime p. Using Dieudonn\'e theory we define a stratification of the corresponding moduli space of…

Number Theory · Mathematics 2008-10-25 Inken Vollaard

We propose an axiomatic approach towards studying unlikely intersections by introducing the framework of distinguished categories. This includes commutative algebraic groups and mixed Shimura varieties. It allows us to define all basic…

Number Theory · Mathematics 2024-11-26 Fabrizio Barroero , Gabriel Andreas Dill

Let $H$ be an open subgroup of a profinite group that can be expressed as intersection of maximal subgroups of $G.$ Given a positive real number $\eta,$ we say that $H$ is an $\eta$-intersection if there exists a family of maximal subgroups…

Group Theory · Mathematics 2017-03-10 Iker de las Heras , Andrea Lucchini

We prove a $p$-adic analogue of the Andr\'{e}-Oort conjecture for subvarieties of the universal abelian varieties containing a dense set of special points. Let $g$ and $n$ be integers with $n \geq 3$ and $p$ a prime number not dividing $n$.…

Algebraic Geometry · Mathematics 2009-11-10 Thomas Scanlon