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Vyacheslav Zakharyuta

Publications and source records attributed to Vyacheslav Zakharyuta.

3 recordsLinked to original sources

The Internal Polya Inequality for $\mathbb{C}$-convex Domains in $\mathbb{C}^n$

Let $K\subset \mathbb{C}$ be a polynomially convex compact set, $f$ be a function analytic in a domain $\overline{\mathbb{C}}\smallsetminus K$ with Taylor expansion $f\left( z\right) =\sum_{k=0}^{\infty }\frac{a_{k}}{z^{k+1}} $ at $\infty $, and $H_{s}\left( f\right) :=\det \left( a_{k+l}\right) _{k,l=0}^{s}$ related Hankel determinants. The classical Polya theorem \cite% {P} says that \[ \limsup_{s\rightarrow \infty }\left\vert H_{s}\left( f\right) \right\vert ^{1/s^{2}}\leq d\left( K\right) , \]% where $d\left( K\right) $ is the transfinite diameter of $K$. The main result of this paper is multivariate internal analogs of Polya's inequality for $\mathbb{C}$-convex (=strictly linearly convex) domains $D\subset \mathbb{C}^{n}$ and weighted Hankel-type determinants, constructed from the Taylor coefficients of a function $f\in A\left( D\right) $ at a given point $% a\in D$; therewith the weights are generated by $s$-indicatrices of the sequence of analytic functionals biorthogonal to the system of monomials in $% \mathbb{C}^{n}$. It is proved by the reduction to the outer multivariate analog of Polya's inequality (Zakharyuta, Math. USSR Sbornik, \textbf{25 }% (1975)) and is based on the characterization of the strict linear convexity in terms of $s$-indicatrices (S. Znamenskii, Siberian Math. J. \textbf{26 } (1985)).

math.CV↗

On Polya' Theorem in Several Complex Variables

Let $K$ be a compact set in $\mathbb{C}$, $f$ a function analytic in $\overline{\mathbb{C}}\smallsetminus K$ vanishing at $\infty $. Let $% f\left( z\right) =\sum_{k=0}^{\infty }a_{k}\ z^{-k-1}$ be its Taylor expansion at $\infty $, and $H_{s}\left( f\right) =\det \left( a_{k+l}\right) _{k,l=0}^{s}$ the sequence of Hankel determinants. The classical Polya inequality says that \[ \limsup\limits_{s\rightarrow \infty }\left\vert H_{s}\left( f\right) \right\vert ^{1/s^{2}}\leq d\left( K\right) , \]% where $d\left( K\right) $ is the transfinite diameter of $K$. Goluzin has shown that for some class of compacta this inequality is sharp. We provide here a sharpness result for the multivariate analog of Polya's inequality, considered by the second author in Math. USSR Sbornik, 25 (1975), 350-364.

math.CV↗

Special polyhedra for Reinhardt domains

We show that every bounded hyperconvex Reinhardt domain can be approximated by special polynomial polyhedra defined by homogeneous polynomial mappings. This is achieved by means of approximation of the pluricomplex Green function of the domain with pole at the origin.

math.CV↗