Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Do Maxwell's equations need revision? - A methodological note   We propose a modification of Maxwell's macroscopic fundamental set of
equations in vacuum in order to clarify Faraday's law of induction. Using this
procedure, the Lorentz force is no longer separate from Maxwell's equations.
The Lorentz transformations are shown to be related to the convective
derivative, which is introduced in the electrodynamics of moving bodies. The
new formulation is in complete agreement with the actual set of Maxwell's
equations for bodies at rest, the only novel feature is a new kind of
electromotive force. Heinrich Hertz was the first to propose a similar
electrodynamic theory of moving bodies, although its interpretation was based
on the existence of the so called "aether". Examining the problem of a moving
circuit with this procedure, it is shown that a new force of induction should
act on a circuit moving through an inhomogeneous vector potential field. This
overlooked induction force is related to the Aharanov-Bohm effect, but can also
be related to the classical electromagnetic field when an external magnetic
field is acting on the system. Technological issues, such as the so called
Marinov motor are also addressed.

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The categories of this paper are: astro-ph
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The categories of this paper are: gr-qc
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The categories of this paper are: nucl-ex
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The categories of this paper are: solv-int
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The categories of this paper are: adap-org
35
The categories of this paper are: mtrl-th
10
The categories of this paper are: q-bio
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The categories of this paper are: q-alg
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The categories of this paper are: chem-ph
12
The categories of this paper are: nucl-th
28
The categories of this paper are: alg-geom
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The categories of this paper are: plasm-ph
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The categories of this paper are: nlin
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The categories of this paper are: atom-ph
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The categories of this paper are: chao-dyn
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The categories of this paper are: cs