Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Faster-Than-Light Solitons in 1 + 1 Dimensions   The existence of a faster-than-light particle is in direct opposition to
Einstein's relativity and the principle of causality. However, we show that the
theory of classical relativistic fields is not inherently inconsistent with the
existence of the faster-than-light particle-like soliton solutions in $1+1$
dimensions. We introduce two extended KG models ($k$-fields) that lead to a
zero-energy and a nonzero-energy stable particle-like solution with faster-than
light speeds, respectively.

33
The categories of this paper are: plasm-ph
6
The categories of this paper are: astro-ph
22
The categories of this paper are: chao-dyn
7
The categories of this paper are: hep-th
19
The categories of this paper are: eess
8
The categories of this paper are: hep-ex
17
The categories of this paper are: q-fin
1
The categories of this paper are: cs
28
The categories of this paper are: alg-geom
36
The categories of this paper are: cmp-lg
23
The categories of this paper are: solv-int
9
The categories of this paper are: nlin
14
The categories of this paper are: math-ph
37
The categories of this paper are: supr-con
15
The categories of this paper are: nucl-ex
21
The categories of this paper are: adap-org