Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Cosmological implications and structure formation from a time varying
  vacuum   We study the dynamics of the FLRW flat cosmological models in which the
vacuum energy varies with time, $\Lambda(t)$. In this model we find that the
main cosmological functions such as the scale factor of the universe and the
Hubble flow are defined in terms of exponential functions. Applying a joint
likelihood analysis of the recent supernovae type Ia data, the Cosmic Microwave
Background shift parameter and the Baryonic Acoustic Oscillations traced by the
Sloan Digital Sky Survey (SDSS) galaxies, we place tight constraints on the
main cosmological parameters of the $\Lambda(t)$ scenario. Also, we compare the
$\Lambda(t)$ model with the traditional $\Lambda$ cosmology and we find that
the former model provides a Hubble expansion which compares well with that of
the $\Lambda$ cosmology. However, the $\Lambda(t)$ scenario predicts stronger
small scale dynamics, which implies a faster growth rate of perturbations with
respect to the usual $\Lambda$-cosmology, despite the fact that they share the
same equation of state parameter. In this framework, we find that galaxy
clusters in the $\Lambda(t)$ model appear to form earlier than in the $\Lambda$
model.

36
The categories of this paper are: cmp-lg
22
The categories of this paper are: chao-dyn
27
The categories of this paper are: comp-gas
7
The categories of this paper are: hep-th
21
The categories of this paper are: adap-org
35
The categories of this paper are: mtrl-th
32
The categories of this paper are: atom-ph
29
The categories of this paper are: funct-an
16
The categories of this paper are: stat
31
The categories of this paper are: ao-sci
8
The categories of this paper are: hep-ex
23
The categories of this paper are: solv-int
4
The categories of this paper are: cond-mat
11
The categories of this paper are: hep-lat
30
The categories of this paper are: q-alg
13
The categories of this paper are: quant-ph