Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Duality of Coordinates and Matter Fields in Curved Spacetime   We show that there exists a duality between the local coordinates and the
solutions of the Klein-Gordon equation in curved spacetime in the same sense as
in the Minkowski spacetime. However, the duality in curved spacetime does not
have the same generality as in flat spacetime and it holds only if the system
satisfies certain constraints. We derive these constraints and the basic
equations of duality and discuss the implications in the quantum theory.

3
The categories of this paper are: physics
4
The categories of this paper are: cond-mat
12
The categories of this paper are: nucl-th
14
The categories of this paper are: math-ph
34
The categories of this paper are: chem-ph
27
The categories of this paper are: comp-gas
33
The categories of this paper are: plasm-ph
16
The categories of this paper are: stat
30
The categories of this paper are: q-alg
2
The categories of this paper are: math
25
The categories of this paper are: patt-sol
0
The categories of this paper are: hep-ph
10
The categories of this paper are: q-bio
20
The categories of this paper are: acc-phys
18
The categories of this paper are: econ
6
The categories of this paper are: astro-ph