Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Entropic Dynamics of Spin   In the Entropic Dynamics (ED) approach the essence of quantum theory lies in
its probabilistic nature while the Hilbert space structure plays a secondary
and ultimately optional role. The dynamics of probability distributions is
driven by the maximization of an entropy subject to constraints that carry the
relevant physical information -- directionality, correlations, gauge
interactions, etc. The challenge is to identify those constraints and to
establish a criterion for how the constraints themselves are updated. In this
paper the ED framework is extended to describe a spin-1/2 point particle. In ED
spin is neither modelled as a rotating body, nor through the motion of a point
particle; it is an epistemic property of the wave function. The constraint that
reflects the peculiar rotational properties of spin is most effectively
expressed in the language of geometric algebra. The updating of all constraints
is carried out in a way that stresses the central importance of symmetry
principles. First we identify the appropriate symplectic and metric structures
in the phase space of probabilities, their conjugate momenta, and the spin
variables. This construction yields a derivation of the Fubini-Study metric for
a spin-1/2 particle which highlights its deep connection to information
geometry. Then we construct an ED that preserves both the symplectic structure
(a Hamiltonian flow) and the metric structure (a Killing flow). We show that
generic Hamiltonian-Killing flows are linear in the wave function. Imposing
further that the Hamiltonian be the generator of an entropic evolution in time
leads to an entropic dynamics described by the Pauli equation. We conclude with
a discussion of the new interpretation of the formalism which yields a physical
picture that is significantly different from that provided by other
interpretations.

15
The categories of this paper are: nucl-ex
10
The categories of this paper are: q-bio
18
The categories of this paper are: econ
19
The categories of this paper are: eess
3
The categories of this paper are: physics
34
The categories of this paper are: chem-ph
25
The categories of this paper are: patt-sol
6
The categories of this paper are: astro-ph
22
The categories of this paper are: chao-dyn
8
The categories of this paper are: hep-ex
32
The categories of this paper are: atom-ph
9
The categories of this paper are: nlin
4
The categories of this paper are: cond-mat
0
The categories of this paper are: hep-ph
26
The categories of this paper are: bayes-an
5
The categories of this paper are: gr-qc