Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Oskar Klein, the sixth dimension and the strength of a magnetic pole   This work extends to six dimensions the idea first proposed by Klein
regarding a closed space in the context of a fifth dimension and its link to
quantum theory. The main result is a formula that expresses the value of the
characteristic length of the sixth dimension in terms of the strength of a
magnetic monopole $g$. It is shown that in the case of Dirac's monopole, the
ratio of the characteristic lengths of the fifth and sixth dimension
corresponds to twice the fine structure constant $\alpha$. Possible
consequences of the idea are discussed.

32
The categories of this paper are: atom-ph
17
The categories of this paper are: q-fin
25
The categories of this paper are: patt-sol
10
The categories of this paper are: q-bio
36
The categories of this paper are: cmp-lg
28
The categories of this paper are: alg-geom
22
The categories of this paper are: chao-dyn
24
The categories of this paper are: dg-ga
31
The categories of this paper are: ao-sci
37
The categories of this paper are: supr-con
7
The categories of this paper are: hep-th
8
The categories of this paper are: hep-ex
29
The categories of this paper are: funct-an
1
The categories of this paper are: cs
20
The categories of this paper are: acc-phys
14
The categories of this paper are: math-ph