Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quantum limits in the measurement of very small displacements in optical
  images   We consider the problem of the measurement of very small displacements in the
transverse plane of an optical image with a split photodetector. We show that
the standard quantum limit for such a measurement, which is equal to the
diffraction limit divided by the square root of the number of photons used in
the measurement, cannot be overcome by use of ordinary single-mode squeezed
light. We give the form of possible multimode nonclassical states of light,
enabling us to enhance by orders of magnitude the resolution of such a
measurement beyond the standard quantum limit.

15
The categories of this paper are: nucl-ex
2
The categories of this paper are: math
31
The categories of this paper are: ao-sci
16
The categories of this paper are: stat
12
The categories of this paper are: nucl-th
30
The categories of this paper are: q-alg
24
The categories of this paper are: dg-ga
27
The categories of this paper are: comp-gas
5
The categories of this paper are: gr-qc
7
The categories of this paper are: hep-th
10
The categories of this paper are: q-bio
26
The categories of this paper are: bayes-an
23
The categories of this paper are: solv-int
18
The categories of this paper are: econ
0
The categories of this paper are: hep-ph
8
The categories of this paper are: hep-ex