Bernstein’s Problem on Weighted Polynomial Approximation

  title={Bernstein’s Problem on Weighted Polynomial Approximation},
  author={Alexei Poltoratski},
  journal={arXiv: Complex Variables},
  • A. Poltoratski
  • Published 12 October 2011
  • Mathematics
  • arXiv: Complex Variables
We formulate a necessary and sufficient condition for polynomials to be dense in a space of continuous functions on the real line, with respect to Bernstein’s weighted uniform norm. Equivalently, for a positive finite measure μ on the real line we give a criterion for density of polynomials in L p (μ). 
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