Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Consequences on some dark energy-candidates from the type Ia supernova
  SN 1997ff   We examine the status of various dark energy-models in light of the recently
observed SN 1997ff at z \approx 1.7. The modified data still fit a pure
cosmological constant \Lambda or a quintessence with an equation of state
similar to that of \Lambda. The kinematical \Lambda-models, \Lambda\sim S^{-2}
and \Lambda\sim H^2, also fit the data reasonably well and require less dark
energy density than is required by the constant \Lambda-model. However, the
model \Lambda\sim S^{-2} with low energy density becomes unphysical as it
cannot accommodate higher redshift objects. We also examine an alternative
explanation of the data, viz., the absorption by the intervening whisker-like
dust and find that the quasi-steady state model and the FRW model \Omega_{\rm
m0}=0.33, {\it without any dark energy} also fit the data reasonably well. We
notice that the addition of SN 1997ff to the old data has worsened the fit to
most of the models, except a closed FRW model with a constant \Lambda and a
closed quintessence-model with \omega_\phi=-0.82, and the models have started
departing from each other as we go above z=1. However, to make a clear
discrimination possible, a few more supernovae with z>1 are required. We have
also calculated the age of the universe in these models and find that, in the
models with a constant \Lambda, the expansion age is uncomfortably close to the
age of the globular clusters. Quintessence-models show even lower age. The
kinematical \Lambda-models are, however, interesting in this connection
(especially the model \Lambda\sim H^2), which give remarkably large age of the
universe.

2
The categories of this paper are: math
18
The categories of this paper are: econ
29
The categories of this paper are: funct-an
28
The categories of this paper are: alg-geom
35
The categories of this paper are: mtrl-th
20
The categories of this paper are: acc-phys
10
The categories of this paper are: q-bio
0
The categories of this paper are: hep-ph
9
The categories of this paper are: nlin
26
The categories of this paper are: bayes-an
3
The categories of this paper are: physics
22
The categories of this paper are: chao-dyn
17
The categories of this paper are: q-fin
1
The categories of this paper are: cs
12
The categories of this paper are: nucl-th
32
The categories of this paper are: atom-ph