Over the past decade, I have worked a fair bit on numerical simulations
mostly in connection with the astrophysics of galaxies. Nowadays, you
need to master N-body codes for cold dark matter simulations, 
hydrodynamic codes to track the gas evolution, and ionization codes
to trace how the gas evolves through different phases (ionized, 
neutral, chemical composition). Much of this work has been carried 
out with colleagues who share a love of theoretical astrophysics:
Ken Freeman (ANU Canberra), Alice Quillen (Rochester NY), Phil Maloney 
(Colorado), Ralph Sutherland (ANU Canberra), Geoff Bicknell (ANU Canberra),
Sanjib Sharma (Sydney) and Geraint Lewis (Sydney).

<p>
A longstanding collaborator is Phil Maloney. Together, we developed the
disk-halo ionization code which purports to map the soft and hard
radiation field throughout the Galactic halo. This is still maintained
by us. The following figure derived from our model appears in 
<a href="http://adsabs.harvard.edu/abs/2005ApJ...630..332F">Fox et al
(2005)</a>:

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<td><img SRC="P/Fox2005.png" width="400"></td>
</tr>


<p>
Another longstanding collaborator is Ralph Sutherland, the author of the
<i>Fyris</i> and <i>Mappings</i> codes. We used these codes in 
understanding how the Magellanic Stream breaks down as it orbits the
Galaxy. 
Research Fellow Thorsten Tepper-Garcia is now extending these simulations.
Here are some relevant movies:
</p>

<p>
Recent work with PhD David Webster 
has concentrated on the minimum mass that a dark halo can
possess if it is to survive a supernova explosion (one shot dwarfs).
</p>

<p>
Geraint Lewis and I have had some successful PhD projects
working with <i>Gadget II</i>. PhD Holly Trowland looked at the alignment
of galaxy spins with large-scale structure as a function of cosmic time.
PhD Tom McCavana looked at galaxy mergers in the early universe.
PhD Matt Nichols (now ETH Fellow in Geneva) has looked at the evolution of 
dwarf galaxies in the Local Group and in nearby groups. PhD Magda
Guglielmo is looking at more realistic orbits for the Magellanic
Clouds and the Magellanic Stream given the latest observations.
</p>

<p>
One of the most exciting software developments is the <i>Galaxia</i>
code led by Sanjib Sharma and me with James Binney (Oxford) and Kathryn
Johnstone (Columbia NY). This is being extended with MCMC techniques
by Sanjib with PhD Prajwal Kafle.
</p>