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Related papers: Weak Approximation for Isotrivial Families

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In this paper we prove that complete families of smooth and projective curves, of genusg>2, in characteristic p>0, with a constant geometric fundamental group, are isotrivial.

Algebraic Geometry · Mathematics 2007-05-23 Mohamed saidi

We completely characterize connected Lie groups all of whose countable subgroups are weakly amenable. We also provide a characterization of connected semisimple Lie groups that are weakly amenable. Finally, we show that a connected Lie…

Functional Analysis · Mathematics 2018-10-17 Søren Knudby

We study deformations of complex projective varieties that are homotopically or homologically trivial. We formulate several conjectures and give some examples and partial answers.

Complex Variables · Mathematics 2012-01-16 Javier Fernandez de Bobadilla , János Kollár

We prove some new relations between weak approximation and some rational equivalence relations (Brauer and R-equivalence) in algebraic groups over arithmetical fields. By using weak approximation and local - global approach, we compute…

alg-geom · Mathematics 2007-05-23 Nguyen Quoc Thang

We give local conditions at the infinite places of a number field K ensuring that the intersection of n quadrics in projective N-space over K, N >> n, satisfies weak approximation.

Number Theory · Mathematics 2007-05-23 Bo-Hae Im , Michael Larsen

Given a family of varieties $X\to \mathbb{P}^n$ over a number field $k$, we determine conditions under which there is a Brauer-Manin obstruction to weak approximation for $100\%$ of the fibres which are everywhere locally soluble.

Number Theory · Mathematics 2019-02-20 M. Bright , T. D. Browning , D. Loughran

We investigate the properties of a family of approximations of the Hasse-Weil $L$-function associated to an elliptic curve $E$ over $\mathbb{Q}$. We give a precise expression for the error of the approximations, and provide a visual…

Number Theory · Mathematics 2023-11-15 Maria Nastasescu , Bogdan Stoica , Alexandru Zaharescu

We present a relatively simple description of binary, definable subsets of models of weakly quasi-o-minimal theories. In particular, we closely describe definable linear orders and prove a weak version of the monotonicity theorem. We also…

Logic · Mathematics 2021-06-01 Slavko Moconja , Predrag Tanović

We show that a sequence of smooth analytic curves of the unit ball of the complex plane, for which the genus is bounded by the area, converges to a lamination in a weak sense.

Complex Variables · Mathematics 2007-05-23 De Thelin Henry

First we solve the problem of finding minimal degree families on toric surfaces by reducing it to lattice geometry. Then we describe how to find minimal degree families on, more generally, rational complex projective surfaces.

Algebraic Geometry · Mathematics 2021-03-09 Niels Lubbes , Josef Schicho

We classify real families of minimal degree rational curves that cover an embedded rational surface. A corollary is that if the projective closure of a smooth surface is not biregular isomorphic to the projective closure of the unit-sphere,…

Algebraic Geometry · Mathematics 2021-03-09 Niels Lubbes

Under some positivity assumptions, extension properties of rationally connected fibrations from a submanifold to its ambient variety are studied. Given a family of rational curves on a complex projective manifold X inducing a covering…

Algebraic Geometry · Mathematics 2008-03-05 Mauro C. Beltrametti , Tommaso de Fernex , Antonio Lanteri

This is the companion piece to "Local-global questions for tori over p-adic function fields" by the first and third authors. We study local-global questions for Galois cohomology over the function field of a curve defined over a p-adic…

Number Theory · Mathematics 2014-01-28 David Harari , Claus Scheiderer , Tamás Szamuely

We generalize to arbitrary dimension our previous construction of simply connected weakly-special but not special varieties. We show that they satisfy the function field and complex analytic part of Campana's conjecture. Moreover, we give…

Algebraic Geometry · Mathematics 2023-08-28 Erwan Rousseau , Carlo Gasbarri , Amos Turchet , Julie Tzu-Yueh Wang

We comment on recent results in the field of information based complexity, which state (in a number of different settings), that approximation of infinitely differentiable functions is intractable and suffers from the curse of…

Numerical Analysis · Mathematics 2013-04-04 Jan Vybiral

We prove some results which give sufficient conditions so that pointwise approximation of negative plurisubharmonic functions on complex varieties by continuous plurisubharmonic ones is possible.

Complex Variables · Mathematics 2016-11-16 Nguyen Quang Dieu , Tang Van Long , Sanphet Ounheuan

We study for rationally connected varieties $X$ the group of degree 2 integral homology classes on $X$ modulo those which are algebraic. We show that the Tate conjecture for divisor classes on surfaces defined over finite fields implies…

Algebraic Geometry · Mathematics 2012-01-17 Claire Voisin

We give necessary and sufficient topological conditions for a simple closed curve on a real rational surface to be approximable by smooth rational curves. We also study approximation by smooth rational curves with given complex…

Algebraic Geometry · Mathematics 2025-05-26 János Kollár , Frédéric Mangolte

In this short note, we observe that Theorem 3.1 in arXiv:1508.00682 for semiorthogonal indecomposability of the derived category of smooth DM stacks based on the canonical bundle can be extended to the case of projective varieties with…

Algebraic Geometry · Mathematics 2021-04-30 Dylan Spence

It is shown that the Joyal quasi-category model structure for simplicial sets extends to a model structure on simplicial presheaves, for which the weak equivalences are local (or stalkwise) Joyal equivalences.

Category Theory · Mathematics 2016-07-20 Nicholas Meadows