Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Repulsive Casimir Force in Chiral Metamaterials   We demonstrate theoretically that one can obtain repulsive Casimir forces and
stable nanolevitations by using chiral metamaterials. By extending the Lifshitz
theory to treat chiral metamaterials, we find that a repulsive force and a
minimum of the interaction energy exist for strong chirality, under realistic
frequency dependencies and correct limiting values (for zero and infinite
frequencies) of the permittivity, permeability, and chiral coefficients.

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The categories of this paper are: q-fin
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The categories of this paper are: q-bio
29
The categories of this paper are: funct-an
34
The categories of this paper are: chem-ph
9
The categories of this paper are: nlin
24
The categories of this paper are: dg-ga
1
The categories of this paper are: cs
11
The categories of this paper are: hep-lat
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The categories of this paper are: nucl-ex
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The categories of this paper are: hep-th
37
The categories of this paper are: supr-con
3
The categories of this paper are: physics
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The categories of this paper are: adap-org
30
The categories of this paper are: q-alg
2
The categories of this paper are: math
14
The categories of this paper are: math-ph