Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Comment on "Observation of Superluminal Behaviors in Wave Propagation"   Mugnai et al. have reported an experiment in which microwave packets appear
to travel in air with a speed substantially greater than c. They calculate the
group velocity of their packets and find that it agrees with their experimental
result. That calculation is incorrect. A correct calculation gives a group
velocity less than c. The reported experimental result cannot be reconciled
with the Maxwell equations.

21
The categories of this paper are: adap-org
16
The categories of this paper are: stat
23
The categories of this paper are: solv-int
5
The categories of this paper are: gr-qc
1
The categories of this paper are: cs
25
The categories of this paper are: patt-sol
37
The categories of this paper are: supr-con
20
The categories of this paper are: acc-phys
12
The categories of this paper are: nucl-th
7
The categories of this paper are: hep-th
24
The categories of this paper are: dg-ga
30
The categories of this paper are: q-alg
10
The categories of this paper are: q-bio
11
The categories of this paper are: hep-lat
28
The categories of this paper are: alg-geom
35
The categories of this paper are: mtrl-th