Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Projection Hypothesis from the von Neumann-type Interaction with a
  Bose-Einstein Condensate   We derive the projection hypothesis in projective quantum measurement by
restricting the set of observables. This projection hypothesis accompanies a
bipartite system with the von Neumann-type interaction, which consists of a
quantum mechanical system, with a meter variable to be measured, and a quantum
field theoretically macroscopic extended object, that is, a spatiotemporally
inhomogeneous Bose-Einstein condensate in quantum field theory with the quantum
coordinate, that is, the zero-energy Goldstone mode(s) of the spontaneously
broken global spatial translational symmetry. The key steps in the derivation
are the return of the symmetry translation of this quantum coordinate to the
inverse translation of the c-number spatial coordinate in quantum field theory
and the reduction of quantum fluctuations to classical fluctuations with
respect to the Goldstone mode(s) due to a superselection rule.

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The categories of this paper are: hep-ph
28
The categories of this paper are: alg-geom
15
The categories of this paper are: nucl-ex
17
The categories of this paper are: q-fin
21
The categories of this paper are: adap-org
2
The categories of this paper are: math
32
The categories of this paper are: atom-ph
27
The categories of this paper are: comp-gas
30
The categories of this paper are: q-alg
23
The categories of this paper are: solv-int
18
The categories of this paper are: econ
29
The categories of this paper are: funct-an
22
The categories of this paper are: chao-dyn
37
The categories of this paper are: supr-con
7
The categories of this paper are: hep-th
16
The categories of this paper are: stat