Displaying similar documents to “On a.e. convergence of expansion with respect to a bounded orthonormal system of polygonals”

Non-similarity of Walsh and trigonometric systems

P. Wojtaszczyk (2000)

Studia Mathematica

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We show that in L p for p ≠ 2 the constants of equivalence between finite initial segments of the Walsh and trigonometric systems have power type growth. We also show that the Riemann ideal norms connected with those systems have power type growth.

An isomorphic Dvoretzky's theorem for convex bodies

Y. Gordon, O. Guédon, M. Meyer (1998)

Studia Mathematica

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We prove that there exist constants C>0 and 0 < λ < 1 so that for all convex bodies K in n with non-empty interior and all integers k so that 1 ≤ k ≤ λn/ln(n+1), there exists a k-dimensional affine subspace Y of n satisfying d ( Y K , B 2 k ) C ( 1 + ( k / l n ( n / ( k l n ( n + 1 ) ) ) ) . This formulation of Dvoretzky’s theorem for large dimensional sections is a generalization with a new proof of the result due to Milman and Schechtman for centrally symmetric convex bodies. A sharper estimate holds for the n-dimensional simplex. ...