Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Conformal symmetry transformations and nonlinear Maxwell equations   We make use of the conformal compactification of Minkowski spacetime $M^{\#}$
to explore a way of describing general, nonlinear Maxwell fields with conformal
symmetry. We distinguish the inverse Minkowski spacetime $[M^{\#}]^{-1}$
obtained via conformal inversion, so as to discuss a doubled compactified
spacetime on which Maxwell fields may be defined. Identifying $M^{\#}$ with the
projective light cone in $(4+2)$-dimensional spacetime, we write two
independent conformal-invariant functionals of the $6$-dimensional Maxwellian
field strength tensors -- one bilinear, the other trilinear in the field
strengths -- which are to enter general nonlinear constitutive equations. We
also make some remarks regarding the dimensional reduction procedure as we
consider its generalization from linear to general nonlinear theories.

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The categories of this paper are: stat
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The categories of this paper are: alg-geom
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The categories of this paper are: q-alg
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The categories of this paper are: ao-sci
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The categories of this paper are: eess
4
The categories of this paper are: cond-mat
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The categories of this paper are: atom-ph
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The categories of this paper are: astro-ph
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The categories of this paper are: supr-con
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The categories of this paper are: chao-dyn
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The categories of this paper are: comp-gas
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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: bayes-an
0
The categories of this paper are: hep-ph
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The categories of this paper are: adap-org