Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The perfect lens on a finite bandwidth   The resolution associated with the so-called perfect lens of thickness $d$ is
$-2\pi d/\ln(|\chi+2|/2)$. Here the susceptibility $\chi$ is a Hermitian
function in $H^2$ of the upper half-plane, i.e., a $H^2$ function satisfying
$\chi(-\omega)=\bar{\chi(\omega)}$. An additional requirement is that the
imaginary part of $\chi$ be nonnegative for nonnegative arguments. Given an
interval $I$ on the positive half-axis, we compute the distance in
$L^\infty(I)$ from a negative constant to this class of functions. This result
gives a surprisingly simple and explicit formula for the optimal resolution of
the perfect lens on a finite bandwidth.

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The categories of this paper are: hep-th
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The categories of this paper are: supr-con
34
The categories of this paper are: chem-ph
35
The categories of this paper are: mtrl-th
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The categories of this paper are: q-bio
30
The categories of this paper are: q-alg
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The categories of this paper are: funct-an
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The categories of this paper are: hep-ex
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The categories of this paper are: cond-mat
1
The categories of this paper are: cs
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The categories of this paper are: solv-int
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The categories of this paper are: cmp-lg
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The categories of this paper are: alg-geom
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The categories of this paper are: q-fin
32
The categories of this paper are: atom-ph
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The categories of this paper are: math-ph