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Polynomial inequalities on algebraic sets

M. Baran, W. Pleśniak (2000)

Studia Mathematica

We give an estimate of Siciak’s extremal function for compact subsets of algebraic varieties in n (resp. n ). As an application we obtain Bernstein-Walsh and tangential Markov type inequalities for (the traces of) polynomials on algebraic sets.

Polytopes, quasi-minuscule representations and rational surfaces

Jae-Hyouk Lee, Mang Xu, Jiajin Zhang (2017)

Czechoslovak Mathematical Journal

We describe the relation between quasi-minuscule representations, polytopes and Weyl group orbits in Picard lattices of rational surfaces. As an application, to each quasi-minuscule representation we attach a class of rational surfaces, and realize such a representation as an associated vector bundle of a principal bundle over these surfaces. Moreover, any quasi-minuscule representation can be defined by rational curves, or their disjoint unions in a rational surface, satisfying certain natural...

Positive polynomials and hyperdeterminants

Fernando Cukierman (2007)

Collectanea Mathematica

Let F be a homogeneous real polynomial of even degree in any number of variables. We consider the problem of giving explicit conditions on the coefficients so that F is positive definite or positive semi-definite. In this note we produce a necessary condition for positivity, and a sufficient condition for non-negativity, in terms of positivity or semi-positivity of a one-variable characteristic polynomial of F. Also, we revisit the known sufficient condition in terms of Hankel matrices.

Positive sheaves of differentials coming from coarse moduli spaces

Kelly Jabbusch, Stefan Kebekus (2011)

Annales de l’institut Fourier

Consider a smooth projective family of canonically polarized complex manifolds over a smooth quasi-projective complex base Y , and suppose the family is non-isotrivial. If Y is a smooth compactification of Y , such that D : = Y Y is a simple normal crossing divisor, then we can consider the sheaf of differentials with logarithmic poles along D . Viehweg and Zuo have shown that for some m > 0 , the m th symmetric power of this sheaf admits many sections. More precisely, the m th symmetric power contains an invertible...

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