Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Mass Power Spectrum in Quintessence Cosmological Models   We present simple analytic approximations for the linear and fully evolved
nonlinear mass power spectrum for spatially flat cold dark matter (CDM)
cosmological models with quintessence (Q). Quintessence is a time evolving,
spatially inhomogeneous energy component with negative pressure and an equation
of state w_Q < 0. It clusters gravitationally on large length scales but
remains smooth like the cosmological constant on small length scales. We show
that the clustering scale is determined by the Compton wavelength of the
Q-field and derive a shape parameter, \Gamma_Q, to characterize the linear mass
power spectrum. The growth of linear perturbations as functions of redshift,
w_Q, and matter density \Omega_m is also quantified. Calibrating to N-body
simulations, we construct a simple extension of the formula by Ma (1998) that
closely approximates the nonlinear power spectrum for a range of plausible QCDM
models.

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The categories of this paper are: funct-an
7
The categories of this paper are: hep-th
10
The categories of this paper are: q-bio
13
The categories of this paper are: quant-ph
1
The categories of this paper are: cs
23
The categories of this paper are: solv-int
2
The categories of this paper are: math
17
The categories of this paper are: q-fin
4
The categories of this paper are: cond-mat
32
The categories of this paper are: atom-ph
25
The categories of this paper are: patt-sol
24
The categories of this paper are: dg-ga
12
The categories of this paper are: nucl-th
15
The categories of this paper are: nucl-ex
19
The categories of this paper are: eess
37
The categories of this paper are: supr-con