Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Parameter Space of Galaxy Formation   Semi-analytic models are a powerful tool for studying the formation of
galaxies. However, these models inevitably involve a significant number of
poorly constrained parameters that must be adjusted to provide an acceptable
match to the observed universe. In this paper, we set out to quantify the
degree to which observational data-sets can constrain the model parameters. By
revealing degeneracies in the parameter space we can hope to better understand
the key physical processes probed by the data. We use novel mathematical
techniques to explore the parameter space of the GALFORM semi-analytic model.
We base our investigation on the Bower et al. 2006 version of GALFORM, adopting
the same methodology of selecting model parameters based on an acceptable match
to the local bJ and K luminosity functions. The model contains 16 parameters
that are poorly constrained, and we investigate this parameter space using the
Model Emulator technique, constructing a Bayesian approximation to the GALFORM
model that can be rapidly evaluated at any point in parameter space. By
combining successive waves of emulation, we show that only 0.26% of the initial
volume is of interest for further exploration. However, within this region we
show that the Bower et al. 2006 model is only one choice from an extended
sub-space of model parameters that can provide equally acceptable fits. We
explore the geometry of this region and begin to explore the physical
connections between parameters that are exposed by this analysis. We also
consider the impact of adding additional observational data to further
constrain the parameter space.

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The categories of this paper are: q-bio
25
The categories of this paper are: patt-sol
28
The categories of this paper are: alg-geom
30
The categories of this paper are: q-alg
3
The categories of this paper are: physics
22
The categories of this paper are: chao-dyn
32
The categories of this paper are: atom-ph
17
The categories of this paper are: q-fin
2
The categories of this paper are: math
20
The categories of this paper are: acc-phys
24
The categories of this paper are: dg-ga
21
The categories of this paper are: adap-org
29
The categories of this paper are: funct-an
34
The categories of this paper are: chem-ph
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The categories of this paper are: nlin
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The categories of this paper are: hep-ex