Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Meissner effect, diamagnetism, and classical physics - a review   We review the literature on what classical physics has to say about the
Meissner effect and the London equations. We first discuss the relevance of the
Bohr-van Leeuwen theorem for the perfect diamagnetism of superconductors. The
conclusion is that the theorem is based on assumptions that are not valid. We
also point out results in the literature which prove that the magnetic flux
expulsion from a sample cooled to superconductivity can be simply understood as
an approach to the magnetostatic energy minimum. These results have been
published several times but still many textbooks on magnetism claim that there
is no classical diamagnetism, and virtually all books on superconductivity
repeat Meissner's 1933 statement that flux expulsion has no classical
explanation.

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The categories of this paper are: solv-int
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The categories of this paper are: chao-dyn
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The categories of this paper are: atom-ph
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The categories of this paper are: mtrl-th
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The categories of this paper are: quant-ph
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The categories of this paper are: chem-ph
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The categories of this paper are: nucl-th
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The categories of this paper are: supr-con
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The categories of this paper are: nucl-ex
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The categories of this paper are: hep-ex
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The categories of this paper are: eess
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The categories of this paper are: gr-qc
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The categories of this paper are: dg-ga
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The categories of this paper are: math
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The categories of this paper are: astro-ph
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The categories of this paper are: math-ph