Anthony Smith

I recently moved this page from where it was at the School of Physics, Sydney University. At that place I played with algorithms to quantify the galaxy distribution with my supervisors, Andrew Hopkins and Richard W. Hunstead. My honours thesis was a study of Extremely Red Galaxies (ERGs) in Phoenix, and here's the paper in which we also introduced an multiscale structure identification algorithm. After much testing and development, we have applied this algorithm, Multiscale Probability Mapping (MSPM), to the Seventh Data Release of the Sloan Digital Sky Survey. Paper is here, and it's pretty! I haven't decided what I'll do with this site, for now I have put it here because I think I need one. I'll think of something. I can be reached via . And me? You mean me, personally? How nice of you to ask!**

**to quote Fwiffo from Star Control.

Recent News

2016 It wasn't so long ago that I didn't listen to any music by vocal artists. But my favourite movie, Memento, features a David Bowie song at the end, Something In The Air. That is exactly the sort of song to hook one to an artist, because it's amazing. Soon after that, "Station To Station" blew my mind. So I became a David Bowie fan - he is the first, and possibly only, vocal artist I will ever know well.

The problem with vocal music, and a large part of why I did not listen to it, is that the music must bend to fit the lyrics. And if music truly means with words, much of its potential to move is lost. But what if a vocal artist had the skill to write lyrics flexible enough to leave the music as unbent as possible? If that artist could bend the lyrics to fit the music instead? I've decided that this is the strength of Bowie's abstract lyrics: that he is not constrained to literal exposition - and there are further possibilities allowed by this approach.

Goodbye David Bowie - heroic artistry, right to the very end. I'm not a musician, but if there is anyone I wish I could be like, it's you - it's the spirit of what you did. I'm your dreamer. Perhaps even your blackstar, in my own way.

DEC 2015 So here I am, in this new place. Maybe later I'll explain the etymology of this domain name.

JAN 2012 This may shock you, but I actually have some science to post here. Our algorithm, Multiscale Probability Mapping (MSPM; formerly known as algorithm X) has been applied to SDSS DR7 to create a catalogue of 10443 galaxy groups and clusters and 53 filaments. Another way to think of this is that we have coarse-grained the galaxy distribution, providing a way to identify cosmic superstructures (filaments in the current application) as unions of groups and clusters. There are pros and cons to coarse-graining at this level rather than the galaxies; some information is lost but some of that information was noise, and noise can throw off algorithms looking for the non-trivial shapes of cosmic superstructure.

Details are in our paper, and pictures are here. As far as we know, no other algorithm has managed a false discovery rate of less than a half for filaments in real data, and we can do a pretty good job with voids this way too. I wrestled with the filament-finding problem for quite some time and am happy about how things have gone. Oh, and this is not the ``stroke of brilliance" I pompously foreshadowed last month, that's something else.

Er, and nor was finding these filaments the hideously stupid act I mentioned; that is a joke I'd love to tell but here's a secret I might actually keep!

DEC 2011 `Accepted 2011 December 15. Received 2011 December 15' plus sweet silence equals . . . something well that's just curious, I guess.

Star Control's Pkunk said that one's good deeds should be balanced by mischief now and again, lest one get so good as to turn completely evil. My version of this is that any hideously stupid act should be balanced by a stroke of brilliance. So here goes.

Places I Like
Sydney Institute for Astronomy, SIfA
My raja, The Backwards Traveller
Star Control

Fear not the Arch Viles and Spectres of the Deepest Reaches,
For the X is strong in this place.

Last Updated - December 2015

Star Control:

The galaxy teems with threatening monsters.
May the Ultron be with you.