Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: How \psi-epistemic models fail at explaining the indistinguishability of
  quantum states   We study the extent to which \psi-epistemic models for quantum measurement
statistics---models where the quantum state does not have a real, ontic
status---can explain the indistinguishability of nonorthogonal quantum states.
This is done by comparing the overlap of any two quantum states with the
overlap of the corresponding classical probability distributions over ontic
states in a \psi-epistemic model. It is shown that in Hilbert spaces of
dimension $d \geq 4$, the ratio between the classical and quantum overlaps in
any \psi-epistemic model must be arbitrarily small for certain nonorthogonal
states, suggesting that such models are arbitrarily bad at explaining the
indistinguishability of quantum states. For dimensions $d$ = 3 and 4, we
construct explicit states and measurements that can be used experimentally to
put stringent bounds on the ratio of classical-to-quantum overlaps in
\psi-epistemic models, allowing one in particular to rule out maximally
\psi-epistemic models more efficiently than previously proposed.

2
The categories of this paper are: math
35
The categories of this paper are: mtrl-th
28
The categories of this paper are: alg-geom
34
The categories of this paper are: chem-ph
29
The categories of this paper are: funct-an
20
The categories of this paper are: acc-phys
23
The categories of this paper are: solv-int
22
The categories of this paper are: chao-dyn
21
The categories of this paper are: adap-org
32
The categories of this paper are: atom-ph
17
The categories of this paper are: q-fin
26
The categories of this paper are: bayes-an
37
The categories of this paper are: supr-con
16
The categories of this paper are: stat
24
The categories of this paper are: dg-ga
19
The categories of this paper are: eess