From Hahn–Banach Type Theorems to the Markov Moment Problem, Sandwich Theorems and Further Applications

  title={From Hahn–Banach Type Theorems to the Markov Moment Problem, Sandwich Theorems and Further Applications},
  author={Octav Olteanu},
The aim of this review paper is to recall known solutions for two Markov moment problems, which can be formulated as Hahn–Banach extension theorems, in order to emphasize their relationship with the following problems: (1) pointing out a previously published sandwich theorem of the type f ≤ h ≤ g, where f, −g are convex functionals and h is an affine functional, over a finite-simplicial set X, and proving a topological version for this result; (2) characterizing isotonicity of convex operators… 
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