Polynomial Cycles in Finitely Generated Domains.
We give an estimate of Siciak’s extremal function for compact subsets of algebraic varieties in (resp. ). As an application we obtain Bernstein-Walsh and tangential Markov type inequalities for (the traces of) polynomials on algebraic sets.
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...
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.
Consider a smooth projective family of canonically polarized complex manifolds over a smooth quasi-projective complex base , and suppose the family is non-isotrivial. If is a smooth compactification of , such that is a simple normal crossing divisor, then we can consider the sheaf of differentials with logarithmic poles along . Viehweg and Zuo have shown that for some , the symmetric power of this sheaf admits many sections. More precisely, the symmetric power contains an invertible...