Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Accelerated Expansion of the Universe based on Emergence of Space and
  Thermodynamics of the Horizon   Researches in the several decades have shown that the dynamics of gravity is
closely related to thermodynamics of the horizon. In this paper, we derive the
Friedmann acceleration equation based on the idea of "emergence of space" and
thermodynamics of the Hubble horizon whose temperature is obtained from the
unified first law of thermodynamics. Then we derive another evolution equation
of the universe based on the energy balance relation $\rho V_{H}=TS$. Combining
the two evolution equations and the equation of state of the cosmic matter, we
obtain the evolution solutions of the FRW universe. We find that the solutions
obtained by us include the solutions obtained in the standard general
relativity(GR) theory. Therefore, it is more general to describe the evolution
of the universe in the thermodynamic way.

24
The categories of this paper are: dg-ga
15
The categories of this paper are: nucl-ex
28
The categories of this paper are: alg-geom
6
The categories of this paper are: astro-ph
34
The categories of this paper are: chem-ph
9
The categories of this paper are: nlin
0
The categories of this paper are: hep-ph
23
The categories of this paper are: solv-int
16
The categories of this paper are: stat
18
The categories of this paper are: econ
11
The categories of this paper are: hep-lat
37
The categories of this paper are: supr-con
26
The categories of this paper are: bayes-an
2
The categories of this paper are: math
35
The categories of this paper are: mtrl-th
4
The categories of this paper are: cond-mat