Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Generalized Ideal Gas Equations for Structureful Universe   We have derived generalized ideal gas equations for a structureful universe
consisting of all forms of matters. We have assumed a universe that contains
superclusters. Superclusters are then made of clusters. Each cluster can be
further divided into smaller ones and so on. We have derived an expression for
the entropy of such a universe. Our model is rather independent of the geometry
of the intermediate clusters. Our calculations are valid for a non-interacting
universe within non-relativistic limits. We suggest that structure formation
can reduce the expansion rate of the universe.

23
The categories of this paper are: solv-int
28
The categories of this paper are: alg-geom
19
The categories of this paper are: eess
25
The categories of this paper are: patt-sol
30
The categories of this paper are: q-alg
27
The categories of this paper are: comp-gas
6
The categories of this paper are: astro-ph
37
The categories of this paper are: supr-con
24
The categories of this paper are: dg-ga
4
The categories of this paper are: cond-mat
21
The categories of this paper are: adap-org
34
The categories of this paper are: chem-ph
14
The categories of this paper are: math-ph
2
The categories of this paper are: math
9
The categories of this paper are: nlin
35
The categories of this paper are: mtrl-th