Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Potentials of a uniformly moving point charge in the Coulomb gauge   The Coulomb-gauge vector potential of a uniformly moving point charge is
obtained by calculating the gauge function for the transformation between the
Lorenz and Coulomb gauges. The expression obtained for the difference between
the vector potentials in the two gauges is shown to satisfy a Poisson equation
to which the inhomogeneous wave equation for this quantity can be reduced. The
right-hand side of the Poisson equation involves an important but easily
overlooked delta-function term that arises from a second-order partial
derivative of the Coulomb potential of a point charge.

2
The categories of this paper are: math
25
The categories of this paper are: patt-sol
14
The categories of this paper are: math-ph
9
The categories of this paper are: nlin
32
The categories of this paper are: atom-ph
34
The categories of this paper are: chem-ph
16
The categories of this paper are: stat
33
The categories of this paper are: plasm-ph
11
The categories of this paper are: hep-lat
26
The categories of this paper are: bayes-an
12
The categories of this paper are: nucl-th
37
The categories of this paper are: supr-con
15
The categories of this paper are: nucl-ex
23
The categories of this paper are: solv-int
8
The categories of this paper are: hep-ex
1
The categories of this paper are: cs