English
Related papers

Related papers: Invariance of the parametric Oka property

200 papers

Let $\mathrm{k}_{0}$ be a field and $W$ a finite orthogonal reflection group over $\mathrm{k}_{0}$. We prove Serre's splitting principle for cohomological invariants of $W$ with values in Rost's cycle modules (over $\mathrm{k}_{0}$) if the…

Algebraic Geometry · Mathematics 2019-09-19 Stefan Gille , Christian Hirsch

Let $\pi: X \longrightarrow C$ be a fibration with reduced fibers over a curve $C$ and consider a polarization $H$ on the surface $X$. Let $E$ be a stable vector bundle of rank $2$ on $C$. We prove that the pullback $\pi^*E$ is a $H-$stable…

Algebraic Geometry · Mathematics 2021-08-17 Graciela Reyes-Ahumada , L. Roa-Leguizamón , H. Torres-López

Let $k$ be an infinite finitely generated field of characteristic $p>0$. Fix a separated scheme $X$ smooth, geometrically connected, and of finite type over $k$ and a smooth proper morphism $f:Y\rightarrow X$. The main result of this paper…

Algebraic Geometry · Mathematics 2025-10-31 Emiliano Ambrosi

Let E be a toric fibration arising from symplectic reduction of a direct sum of line bundles over (almost-) K\"ahler base B. Then each torus-fixed point of the toric manifold fiber defines a section of the fibration. Let L_a be convex line…

Algebraic Geometry · Mathematics 2015-10-06 Jeff Brown

We study deformation theory of elliptic fibre bundles over curves in positive characteristics. As applications, we give examples of non-liftable elliptic surfaces in charactertic two and three, which answers a question of Katsura and Ueno.…

Algebraic Geometry · Mathematics 2015-01-14 Holger Partsch

Topological insulators are insulating in the bulk but feature conducting states on their surfaces. Standard methods for probing their topological properties largely involve probing the surface, even though topological invariants are defined…

Roughly speaking, holonomic measures are parametric varifolds without boundary. They provide a setting appropriate for the analysis of many variational problems. In this paper, we characterize the space of variations for these objects, and…

Optimization and Control · Mathematics 2015-04-09 Rodolfo Rios-Zertuche

Let $A$ be an integral $k$-algebra of finite type over an algebraically closed field $k$ of characteristic $p>0$. Given a collection ${\cal{D}}$ of $k$-derivations on $A$, that we interpret as algebraic vector fields on $X=Spec(A)$, we…

Algebraic Geometry · Mathematics 2007-05-23 Philippe Bonnet

Let $\pi\cln X\to \Delta^m$ be a proper smooth K\"ahler morphism from a complex manifold $X$ to the unit polydisc $\Delta^m$. Suppose the fibers over the complement of a proper analytic subset are biholomorphic to a fixed projective…

Algebraic Geometry · Mathematics 2026-05-11 Mu-Lin Li , Xiao-Lei Liu

We prove that a set of finite perimeter is indecomposable if and only if it is, up to a choice of suitable representative, connected in the 1-fine topology. This gives a topological characterization of indecomposability which is new even in…

Metric Geometry · Mathematics 2025-12-23 Paolo Bonicatto , Panu Lahti , Enrico Pasqualetto

For a complex polynomial in two variables we study the morphism induced in homology by the embedding of an irregular fiber in a regular neighborhood of it. We give necessary and sufficient conditions for this morphism to be injective,…

Algebraic Geometry · Mathematics 2007-05-23 Arnaud Bodin

In this paper, we first show that for a countable family of random elements taking values in a partially ordered Polish space (POP), association (both positive and negative) of all finite dimensional marginals implies that of the infinite…

Probability · Mathematics 2019-12-04 Guenter Last , Ryszard Szekli , D. Yogeshwaran

Given a closed orientable surface (\Sigma) of genus at least two, we establish an affine isomorphism between the convex compact set of isotopy-invariant topological measures on (\Sigma) and the convex compact set of additive functions on…

General Topology · Mathematics 2009-03-17 Frol Zapolsky

In this paper we study the question of when does a closed, simply connected, integral symplectic manifold (W,omega) have the stability property for its spaces of based holomorphic spheres? This property states that in a stable limit under…

Symplectic Geometry · Mathematics 2016-09-07 Ralph L. Cohen , John D. S. Jones , Graeme B. Segal

We give an explicit example of a fibration $f \colon X \to Y$ between smooth projective varieties whose "orbifold base" $\Delta_f$ in the sense of Campana has the property that the induced morphism $X \to (Y, \Delta_f)$ is not a morphism of…

Algebraic Geometry · Mathematics 2026-03-09 Finn Bartsch

In this thesis, we develop the theory of bifibrations of polycategories. We start by studying how to express certain categorical structures as universal properties by generalising the shape of morphism. We call this phenomenon…

Category Theory · Mathematics 2023-05-25 Nicolas Blanco

Taking an elementary and straightforward approach, we develop the concept of a regular value for a smooth map f: O -> P between smooth orbifolds O and P. We show that Sard's theorem holds and that the inverse image of a regular value is a…

Differential Geometry · Mathematics 2013-07-11 Joseph E. Borzellino , Victor Brunsden

We introduce a notion of characteristic for connective $p$-local $E_\infty$ ring spectra and study some basic properties. Apart from examples already pointed out by Markus Szymik, we investigate some examples built from Hopf invariant $1$…

Algebraic Topology · Mathematics 2017-06-02 Andrew Baker

Let $X$ be a normal complex variety and $\pi:\tilde X \to X$ a resolution of singularities. We show that the inclusion morphism $\pi_*\Omega_{\tilde X}^p\hookrightarrow \Omega_X^{[p]}$ is an isomorphism for $p <…

Algebraic Geometry · Mathematics 2024-12-03 Benjamin Tighe

Given a dynamical system, we say that a performance function has property P if its time averages along orbits are maximized at a periodic orbit. It is conjectured by several authors that for sufficiently hyperbolic dynamical systems,…

Dynamical Systems · Mathematics 2015-11-09 Jairo Bochi , Yiwei Zhang