Misc,
The cosmological simulation code $CONCEPT\, 1.0$
(2021)cite arxiv:2112.01508Comment: 27 pages, 13 figures, for the code see https://github.com/jmd-dk/concept.
Abstract
We present version 1.0 of the cosmological simulation code $\rm
CONCEPT$, designed for simulations of large-scale structure formation.
$CONCEPT\, 1.0$ contains a P$^3$M gravity solver, with
the short-range part implemented using a novel (sub)tiling strategy, coupled
with individual and adaptive particle time-stepping. In addition to this,
$CONCEPT$ contains a (linear or non-linear) fluid
solver to treat non-baryonic components which are not easily treatable using
the particle implementation. This allows e.g. for the inclusion of non-linear
massive neutrinos (which may be relativistic) and for simulations that are
consistent with general relativistic perturbation theory. Decaying dark matter
scenarios are also fully supported. A primary objective of $\rm
CONCEPT$ is ease of use. To this end, it has built-in initial condition
generation and can produce output in the form of snapshots, power spectra and
direct visualisations. It also comes with a robust installation script and
thorough documentation. $CONCEPT$ is the first
massively parallel cosmological simulation code written in Python. Despite of
this, excellent performance is obtained, even comparing favourably to other
codes such as $GADGET$ at similar precision, in the case of
low to moderate clustering. We find extraordinary good agreement between
results produced using $CONCEPT\, 1.0$ and
$GADGET$, at all scales and times. The $\rm
CONCEPT$ code itself along with documentation is openly released at
https://github.com/jmd-dk/concept .
