Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Attenuation and damping of electromagnetic fields: Influence of inertia
  and displacement current   New results for attenuation and damping of electromagnetic fields in rigid
conducting media are derived under the conjugate influence of inertia due to
charge carriers and displacement current. Inertial effects are described by a
relaxation time for the current density in the realm of an extended Ohm's law.
The classical notions of poor and good conductors are rediscussed on the basis
of an effective electric conductivity, depending on both wave frequency and
relaxation time. It is found that the attenuation for good conductors at high
frequencies depends solely on the relaxation time. This means that the
penetration depth saturates to a minimum value at sufficiently high
frequencies. It is also shown that the actions of inertia and displacement
current on damping of magnetic fields are opposite to each other. That could
explain why the classical decay time of magnetic fields scales approximately as
the diffusion time. At very small length scales, the decay time could be given
either by the relaxation time or by a fraction of the diffusion time, depending
whether inertia or displacement current, respectively, would prevail on
magnetic diffusion.

13
The categories of this paper are: quant-ph
23
The categories of this paper are: solv-int
28
The categories of this paper are: alg-geom
14
The categories of this paper are: math-ph
5
The categories of this paper are: gr-qc
35
The categories of this paper are: mtrl-th
2
The categories of this paper are: math
33
The categories of this paper are: plasm-ph
7
The categories of this paper are: hep-th
12
The categories of this paper are: nucl-th
34
The categories of this paper are: chem-ph
31
The categories of this paper are: ao-sci
15
The categories of this paper are: nucl-ex
27
The categories of this paper are: comp-gas
11
The categories of this paper are: hep-lat
22
The categories of this paper are: chao-dyn