Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quantum fields and "Big Rip" expansion singularities   The effects of quantized conformally invariant massless fields on the
evolution of cosmological models containing a ``Big Rip'' future expansion
singularity are examined. Quantized scalar, spinor, and vector fields are found
to strengthen the accelerating expansion of such models as they approach the
expansion singularity.

4
The categories of this paper are: cond-mat
34
The categories of this paper are: chem-ph
25
The categories of this paper are: patt-sol
14
The categories of this paper are: math-ph
11
The categories of this paper are: hep-lat
29
The categories of this paper are: funct-an
19
The categories of this paper are: eess
26
The categories of this paper are: bayes-an
21
The categories of this paper are: adap-org
36
The categories of this paper are: cmp-lg
20
The categories of this paper are: acc-phys
17
The categories of this paper are: q-fin
6
The categories of this paper are: astro-ph
28
The categories of this paper are: alg-geom
37
The categories of this paper are: supr-con
7
The categories of this paper are: hep-th