Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Is the Quantum Hall Effect influenced by the gravitational field?   Most of the experiments on the quantum Hall effect (QHE) were made at
approximately the same height above sea level. A future international
comparison will determine whether the gravitational field $\mathbf{g}(x)$
influences the QHE. In the realm of (1 + 2)-dimensional phenomenological
macroscopic electrodynamics, the Ohm-Hall law is metric independent
(`topological'). This suggests that it does not couple to $\mathbf{g}(x)$. We
corroborate this result by a microscopic calculation of the Hall conductance in
the presence of a post-Newtonian gravitational field.

15
The categories of this paper are: nucl-ex
14
The categories of this paper are: math-ph
20
The categories of this paper are: acc-phys
34
The categories of this paper are: chem-ph
23
The categories of this paper are: solv-int
6
The categories of this paper are: astro-ph
18
The categories of this paper are: econ
19
The categories of this paper are: eess
9
The categories of this paper are: nlin
2
The categories of this paper are: math
35
The categories of this paper are: mtrl-th
7
The categories of this paper are: hep-th
30
The categories of this paper are: q-alg
3
The categories of this paper are: physics
25
The categories of this paper are: patt-sol
24
The categories of this paper are: dg-ga