Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Geometry and Spectrum of Casimir Forces   We present a new approach to the Helmholtz spectrum for arbitrarily shaped
boundaries and general boundary conditions. We derive the boundary induced
change of the density of states in terms of the free Green's function from
which we obtain non-perturbative results for the Casimir interaction between
rigid surfaces. As an example, we compute the lateral electrodynamic force
between two corrugated surfaces over a wide parameter range. Universal
behavior, fixed only by the largest wavelength component of the surface shape,
is identified at large surface separations, complementing known short distance
expansions which we also reproduce with high precision.

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The categories of this paper are: physics
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The categories of this paper are: acc-phys
14
The categories of this paper are: math-ph
18
The categories of this paper are: econ
2
The categories of this paper are: math
27
The categories of this paper are: comp-gas
28
The categories of this paper are: alg-geom
32
The categories of this paper are: atom-ph
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The categories of this paper are: hep-ph
36
The categories of this paper are: cmp-lg
37
The categories of this paper are: supr-con
24
The categories of this paper are: dg-ga
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The categories of this paper are: nlin
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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: gr-qc