Y. Sarantopoulos | Searcharxiv

arXiv2020

Bernstein and Markov-type inequalities for polynomials on $L_{p}(μ)$ spaces

In this work, we discuss generalizations of the classical Bernstein and Markov type inequalities for polynomials and we present some new inequalities for the $k$th Fréchet derivative of homogeneous polynomials on real and complex $L_{p}(μ)$ spaces. We also give applications to homogeneous polynomials and symmetric multilinear mappings in $L_{p}(μ)$ spaces. Finally, Bernstein's inequality for homogeneous polynomials on both real and complex Hilbert spaces has been discussed.

math.FA↗

arXiv2011

Circle products as restrictions of the square product

We equip the tensor algebra of a vector space $U$ over the real or complex field with an alternative product. The new product has the property that if we specialize it to the symmetric tensor algebra becomes the circle product introduced by Brouder while specialization to the antisymmetric algebra becomes the circle product introduced by Rota and Stein. We prove some interesting properties of this product analogous to the properties proved by the previous authors. We use Hopf algebraic methods to simplify our results. Finally we prove that the classical algebraic structure of the tensor algebra and the new one are homomorphically isomorphic.\bigskip

math.QA↗