Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Neutrino propagation in media: Flavor-, helicity-, and pair correlations   Neutrinos propagating in media (matter and electromagnetic fields) undergo
flavor and helicity oscillations, where helicity transitions are instigated
both by electromagnetic fields and matter currents. In addition, it has been
shown that correlations between neutrinos and antineutrinos of opposite
momentum can build up in anisotropic media. We re-derive the neutrino equations
of motion in the mean-field approximation for homogeneous yet anisotropic
media, confirming previous results except for a small correction in the
Majorana case. Furthermore, we derive the mean-field Hamiltonian induced by
neutrino electromagnetic interactions. We also provide a phenomenological
discussion of pair correlations in comparison with helicity correlations.

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The categories of this paper are: gr-qc
27
The categories of this paper are: comp-gas
10
The categories of this paper are: q-bio
29
The categories of this paper are: funct-an
2
The categories of this paper are: math
30
The categories of this paper are: q-alg
32
The categories of this paper are: atom-ph
8
The categories of this paper are: hep-ex
17
The categories of this paper are: q-fin
36
The categories of this paper are: cmp-lg
28
The categories of this paper are: alg-geom
15
The categories of this paper are: nucl-ex
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The categories of this paper are: astro-ph
20
The categories of this paper are: acc-phys
25
The categories of this paper are: patt-sol
22
The categories of this paper are: chao-dyn