Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Constitution and model. The quantum theory of Bohr and imagining the
  atom   The quantum theory of Bohr has roots in the theories of Rutherford and J. J.
Thomson on the one hand, and that of Nicholson on the other. We note that Bohr
neither presented the theories of Rutherford and Thomson faithfully, nor did he
refer to the theory of Nicholson in its own terms. The contrasting attitudes
towards these antecedent theories is telling and reveals the philosophical
disposition of Bohr. We argue that Bohr intentionally avoided the concept of
model as inappropriate for describing his proposed theory. Bohr had no problem
in referring to the works of others as 'models', thus separating his theory
from previous theories. He was interested in uncovering 'a little piece of
reality'.

12
The categories of this paper are: nucl-th
21
The categories of this paper are: adap-org
5
The categories of this paper are: gr-qc
34
The categories of this paper are: chem-ph
25
The categories of this paper are: patt-sol
0
The categories of this paper are: hep-ph
7
The categories of this paper are: hep-th
32
The categories of this paper are: atom-ph
29
The categories of this paper are: funct-an
9
The categories of this paper are: nlin
22
The categories of this paper are: chao-dyn
15
The categories of this paper are: nucl-ex
27
The categories of this paper are: comp-gas
18
The categories of this paper are: econ
24
The categories of this paper are: dg-ga
6
The categories of this paper are: astro-ph