Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Current-sheet formation in incompressible electron magnetohydrodynamics   The nonlinear dynamics of axisymmetric, as well as helical, frozen-in vortex
structures is investigated by the Hamiltonian method in the framework of ideal
incompressible electron magnetohydrodynamics. For description of current-sheet
formation from a smooth initial magnetic field, local and nonlocal nonlinear
approximations are introduced and partially analyzed that are generalizations
of the previously known exactly solvable local model neglecting electron
inertia. Finally, estimations are made that predict finite-time singularity
formation for a class of hydrodynamic models intermediate between that local
model and the Eulerian hydrodynamics.

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The categories of this paper are: econ
6
The categories of this paper are: astro-ph
28
The categories of this paper are: alg-geom
14
The categories of this paper are: math-ph
24
The categories of this paper are: dg-ga
35
The categories of this paper are: mtrl-th
12
The categories of this paper are: nucl-th
22
The categories of this paper are: chao-dyn
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The categories of this paper are: hep-lat
1
The categories of this paper are: cs
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The categories of this paper are: hep-th
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The categories of this paper are: acc-phys
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The categories of this paper are: eess
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The categories of this paper are: nucl-ex
31
The categories of this paper are: ao-sci
16
The categories of this paper are: stat