Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Path Integrals over Measurement Amplitudes: Practical Quantum
  Foundations for Signal Processing and Control   It is shown that classical control diagrams can be mapped one-to-one onto
quantum path integrals over measurement amplitudes. To show the practical
utility of this method, exact closed-form expressions are derived for the
control dynamics and quantum noise levels of a test mass observed by a
Fabry-Perot interferometer. This formalism provides an efficient yet rigorous
method for analyzing complex systems such as interferometric gravity wave
detectors and magnetic resonance force microscopy (MRFM) experiments. Quantum
limits are conjectured for the sensitivity of interferometric observation of
test mass trajectories.

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The categories of this paper are: hep-lat
33
The categories of this paper are: plasm-ph
2
The categories of this paper are: math
15
The categories of this paper are: nucl-ex
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The categories of this paper are: gr-qc
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The categories of this paper are: adap-org
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The categories of this paper are: nlin
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The categories of this paper are: econ
8
The categories of this paper are: hep-ex
29
The categories of this paper are: funct-an
3
The categories of this paper are: physics
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The categories of this paper are: eess
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The categories of this paper are: comp-gas
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The categories of this paper are: nucl-th
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The categories of this paper are: cmp-lg
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The categories of this paper are: mtrl-th