Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Bernstein's problem on weighted polynomial approximation   We formulate and discuss 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 $\mu$ on the real line we give a criterion for density of polynomials
in $L^p(\mu)$.

9
The categories of this paper are: nlin
36
The categories of this paper are: cmp-lg
11
The categories of this paper are: hep-lat
35
The categories of this paper are: mtrl-th
7
The categories of this paper are: hep-th
34
The categories of this paper are: chem-ph
13
The categories of this paper are: quant-ph
16
The categories of this paper are: stat
5
The categories of this paper are: gr-qc
28
The categories of this paper are: alg-geom
12
The categories of this paper are: nucl-th
6
The categories of this paper are: astro-ph
19
The categories of this paper are: eess
20
The categories of this paper are: acc-phys
0
The categories of this paper are: hep-ph
15
The categories of this paper are: nucl-ex