Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Gravitational self-interactions of a degenerate quantum scalar field   We develop a formalism to help calculate in quantum field theory the
departures from the description of a system by classical field equations. We
apply the formalism to a homogeneous condensate with attractive contact
interactions and to a homogeneous self-gravitating condensate in critical
expansion. In their classical descriptions, such condensates persist forever.
We show that in their quantum description, parametric resonance causes quanta
to jump in pairs out of the condensate into all modes with wavector less than
some critical value. We calculate in each case the time scale over which the
homogeneous condensate is depleted, and after which a classical description is
invalid. We argue that the duration of classicality of inhomogeneous
condensates is shorter than that of homogeneous condensates.

31
The categories of this paper are: ao-sci
11
The categories of this paper are: hep-lat
24
The categories of this paper are: dg-ga
2
The categories of this paper are: math
29
The categories of this paper are: funct-an
25
The categories of this paper are: patt-sol
20
The categories of this paper are: acc-phys
32
The categories of this paper are: atom-ph
18
The categories of this paper are: econ
14
The categories of this paper are: math-ph
22
The categories of this paper are: chao-dyn
19
The categories of this paper are: eess
5
The categories of this paper are: gr-qc
15
The categories of this paper are: nucl-ex
28
The categories of this paper are: alg-geom
13
The categories of this paper are: quant-ph