Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On gravity as an entropic force   We consider E. Verlinde's proposal that gravity is an entropic force -- we
shall call this theory entropic gravity (EG) -- and reanalyze a recent claim
that this theory is in contradiction with the observation of the
gravitationally-bound ground state of neutrons in the GRANIT experiment. We
find that EG does not necessarily contradict the existence of
gravitationally-bound quantum states of neutrons in the Earth's gravitational
field, since EG is equivalent to Newtonian gravity in this case. However,
certain transitions between the gravitationally-bound quantum states of
neutrons, in particular spontaneous decays of excited states, which can
hopefully be observed in future experiments, cannot be explained in the
framework of EG, unless essential ingredients are introduced into it.
Otherwise, a quantized description of gravity will be required.

25
The categories of this paper are: patt-sol
11
The categories of this paper are: hep-lat
36
The categories of this paper are: cmp-lg
26
The categories of this paper are: bayes-an
29
The categories of this paper are: funct-an
3
The categories of this paper are: physics
32
The categories of this paper are: atom-ph
21
The categories of this paper are: adap-org
17
The categories of this paper are: q-fin
28
The categories of this paper are: alg-geom
24
The categories of this paper are: dg-ga
8
The categories of this paper are: hep-ex
20
The categories of this paper are: acc-phys
1
The categories of this paper are: cs
35
The categories of this paper are: mtrl-th
33
The categories of this paper are: plasm-ph