Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Maximal boost and energy of elementary particles as a manifestation of
  the limit of localizability of elementary quantum systems   I discuss an upper bound on the boost and the energy of elementary particles.
The limit is derived utilizing the core principle of relativistic quantum
mechanics stating that there is a lower bound for localization of an elementary
quantum system and the assumption that when the localization scale reaches the
Planck length, elementary particles are removed from the S-matrix observables.
The limits for the boost and energy, M_{Planck}/m and
M_{Planck}c^{2}\approx\,8.6 * 10^{27} eV, are defined in terms of fundamental
constants and the mass of elementary particle and does not involve any dynamic
scale. These bounds imply that the cosmic ray flux of any flavor may stretch up
to energies of order 10^{18} GeV and will cut off around this value.

13
The categories of this paper are: quant-ph
21
The categories of this paper are: adap-org
36
The categories of this paper are: cmp-lg
35
The categories of this paper are: mtrl-th
27
The categories of this paper are: comp-gas
34
The categories of this paper are: chem-ph
8
The categories of this paper are: hep-ex
2
The categories of this paper are: math
1
The categories of this paper are: cs
30
The categories of this paper are: q-alg
24
The categories of this paper are: dg-ga
32
The categories of this paper are: atom-ph
31
The categories of this paper are: ao-sci
9
The categories of this paper are: nlin
37
The categories of this paper are: supr-con
28
The categories of this paper are: alg-geom