Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Nature as the observer: A simplified approach to the measurement problem
  and related issues   Several theories have been advanced recently which appear to offer a
resolution to that portion of the measurement problem which previously dealt
with a possible reduction of the state vector in a subjective fashion by the
brain, mind or consciousness. It now appears, based on both biological and
mathematical analysis, that collapse of the wave function always takes place in
an objective fashion in the retinal rod-rhodopsin molecule, and that only
measured information is ever presented to the brain, mind or consciousness for
possible subjective analysis. The remaining portion of the measurement problem
has to do with the use and legitimacy of such terms as boundary (Heisenberg or
von Neumann cut), information, irreversible, measurement, microscopic,
macroscopic, observer (apparatus or measuring system), observed (measured
system) and wave function collapse. This portion of the measurement problem may
be resolved in two ways. First, by adopting Dirac's theory that it is nature
that makes the choice of measuremental result. Second, by the insertion of a
mesoscopic bridge between the microscopic and macroscopic worlds, in the
existing form of the rhodopsin molecule with its retinal and opsin components.

29
The categories of this paper are: funct-an
16
The categories of this paper are: stat
26
The categories of this paper are: bayes-an
32
The categories of this paper are: atom-ph
14
The categories of this paper are: math-ph
19
The categories of this paper are: eess
35
The categories of this paper are: mtrl-th
30
The categories of this paper are: q-alg
0
The categories of this paper are: hep-ph
6
The categories of this paper are: astro-ph
11
The categories of this paper are: hep-lat
21
The categories of this paper are: adap-org
1
The categories of this paper are: cs
12
The categories of this paper are: nucl-th
25
The categories of this paper are: patt-sol
7
The categories of this paper are: hep-th