Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Ground State Energy of Heavy Atoms According to Brown and Ravenhall:
  Absence of Relativistic Effects in Leading Order   It is shown that the ground state energy of heavy atoms is, to leading order,
given by the non-relativistic Thomas-Fermi energy. The proof is based on the
relativistic Hamiltonian of Brown and Ravenhall which is derived from quantum
electrodynamics yielding energy levels correctly up to order $\alpha^2$Ry.

15
The categories of this paper are: nucl-ex
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The categories of this paper are: hep-ex
6
The categories of this paper are: astro-ph
28
The categories of this paper are: alg-geom
32
The categories of this paper are: atom-ph
9
The categories of this paper are: nlin
25
The categories of this paper are: patt-sol
37
The categories of this paper are: supr-con
10
The categories of this paper are: q-bio
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The categories of this paper are: q-fin
30
The categories of this paper are: q-alg
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The categories of this paper are: ao-sci
11
The categories of this paper are: hep-lat
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The categories of this paper are: cs
3
The categories of this paper are: physics
5
The categories of this paper are: gr-qc