Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Carroll versus Newton and Galilei: two dual non-Einsteinian concepts of
  time   The Carroll group was originally introduced by Levy-Leblond [1] by
considering the limit of the Poincar\'e group as $c\to0$. In this paper an
alternative definition, based on the geometric properties of a non-Minkowskian,
non-Galilean but nevertheless boost-invariant, space-time structure is
proposed. A "duality" with the Galilean limit $c\to\infty$ is established. Our
theory is illustrated by Carrollian electromagnetism.

29
The categories of this paper are: funct-an
34
The categories of this paper are: chem-ph
0
The categories of this paper are: hep-ph
25
The categories of this paper are: patt-sol
9
The categories of this paper are: nlin
28
The categories of this paper are: alg-geom
19
The categories of this paper are: eess
20
The categories of this paper are: acc-phys
23
The categories of this paper are: solv-int
12
The categories of this paper are: nucl-th
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The categories of this paper are: nucl-ex
24
The categories of this paper are: dg-ga
33
The categories of this paper are: plasm-ph
18
The categories of this paper are: econ
8
The categories of this paper are: hep-ex
22
The categories of this paper are: chao-dyn