Abstract
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).
The author is supported by N.S.F. grant DMS-1101278.
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Acknowledgements
I am grateful to Nikolai Makarov and Misha Sodin for introducing me to the general area of Bernstein’s problem and for valuable discussions.
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Poltoratski, A. (2015). Bernstein’s Problem on Weighted Polynomial Approximation. In: Gröchenig, K., Lyubarskii, Y., Seip, K. (eds) Operator-Related Function Theory and Time-Frequency Analysis. Abel Symposia, vol 9. Springer, Cham. https://doi.org/10.1007/978-3-319-08557-9_6
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DOI: https://doi.org/10.1007/978-3-319-08557-9_6
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