Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Remarks on the derivation and evaluation of the Stacey-Sigmar model for
  tokamak equilibrium   The Stacey-Sigmar model for tokamak equilibrium as presented in the
literature relies heavily on the neoclassical theory of the electrostatic
field. Its neglect of Gauss's law is inconsistent with the potential
formulation of electrodynamics. Its treatment of the dynamic electric field
generated by the central heating and poloidal field coils also is suspect. Its
derivation of the viscosity term remains incomplete and does not account for
the varying pitch angle of the magnetic field. A derivation of the viscosity
term which respects the pitch angle can account for the radial force commonly
ascribed to the radial electrostatic field, thereby obviating the desire to
neglect Gauss's law.

9
The categories of this paper are: nlin
29
The categories of this paper are: funct-an
20
The categories of this paper are: acc-phys
34
The categories of this paper are: chem-ph
22
The categories of this paper are: chao-dyn
14
The categories of this paper are: math-ph
19
The categories of this paper are: eess
37
The categories of this paper are: supr-con
4
The categories of this paper are: cond-mat
36
The categories of this paper are: cmp-lg
11
The categories of this paper are: hep-lat
12
The categories of this paper are: nucl-th
21
The categories of this paper are: adap-org
0
The categories of this paper are: hep-ph
35
The categories of this paper are: mtrl-th
16
The categories of this paper are: stat