Distortion and Critical Values of the Finite Blaschke Product

An upper bound for the least critical values of finite Blaschke products

“…Apart from other results, in the recent paper [6] we found the greatest lower bound for the maximum modulus of the critical values of products B normalized by the conditions B(0) = 0 and B ′ (0) ̸ = 0 (see [6], Corollary 5.3). In this case the extremal function coincides with the so-called Chebyshev-Blaschke product (see [2]) up to a linear fractional change of independent variable.…”