Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Fast & accurate emulation of two-body scattering observables without
  wave functions   We combine Newton's variational method with ideas from eigenvector
continuation to construct a fast & accurate emulator for two-body scattering
observables. The emulator will facilitate the application of rigorous
statistical methods for interactions that depend smoothly on a set of free
parameters. Our approach begins with a trial $K$ or $T$ matrix constructed from
a small number of exact solutions to the Lippmann--Schwinger equation.
Subsequent emulation only requires operations on small matrices. We provide
several applications to short-range potentials with and without the Coulomb
interaction and partial-wave coupling. It is shown that the emulator can
accurately extrapolate far from the support of the training data. When used to
emulate the neutron-proton cross section with a modern chiral interaction as a
function of 26 free parameters, it reproduces the exact calculation with
negligible error and provides an over 300x improvement in CPU time.

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The categories of this paper are: mtrl-th
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The categories of this paper are: supr-con
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The categories of this paper are: q-fin
10
The categories of this paper are: q-bio
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The categories of this paper are: quant-ph
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The categories of this paper are: bayes-an
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The categories of this paper are: acc-phys
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The categories of this paper are: nlin
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The categories of this paper are: solv-int
1
The categories of this paper are: cs
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The categories of this paper are: plasm-ph
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The categories of this paper are: cmp-lg
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The categories of this paper are: chao-dyn
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The categories of this paper are: chem-ph
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The categories of this paper are: ao-sci
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The categories of this paper are: hep-ex