Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A search for the minimal unified field theory. I. Parallel transport of
  Dirac field   Two real vector fields are revealed as spin connections of the spinor field,
which is introduced as a representation of the local Lorentz group by Dirac
spinors. One of these fields is identified as the Maxwell field. Another one is
the axial field, which is sufficient to describe parity nonconservation effects
in atoms and it is sensitive to the second internal degree of freedom of the
Dirac spinor field. The polarization associated with this degree of freedom is
a distinctive characteristic of the Dirac spinor field in spatially closed
localized states. The short-distance behavior of the axial field can lead to a
not self-adjoint Dirac Hamiltonian and trigger a ``falling onto a centre''
phenomenon. In the second part of this work, the axial field will be linked to
the gravity.

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The categories of this paper are: patt-sol
22
The categories of this paper are: chao-dyn
19
The categories of this paper are: eess
17
The categories of this paper are: q-fin
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The categories of this paper are: acc-phys
21
The categories of this paper are: adap-org
9
The categories of this paper are: nlin
16
The categories of this paper are: stat
35
The categories of this paper are: mtrl-th
11
The categories of this paper are: hep-lat
10
The categories of this paper are: q-bio
8
The categories of this paper are: hep-ex
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The categories of this paper are: solv-int
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The categories of this paper are: funct-an
15
The categories of this paper are: nucl-ex
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The categories of this paper are: bayes-an