I’ve only just recently heard of the concept of a light cone, one of many interesting facts I’ve learnt whilst reading Impossibility by John Barrow.
You can visualise it as a simple X-Y graph. The X-axis is space and the Y-axis is time. Any given point in space-time has both a past and a future light cone.

A past light cone represents the space from which light can be received at a given point in space-time. The future light cone represents the space that will eventually be filled by light emitted at that point.
Light cones are described in Impossibility because Barrow observes that the visible universe is described by just such a light cone. The inflationary universe hypothesis means that the actual universe is much larger but we can never get to see it, as our horizon is only expanding at the speed of light. All our observations of the universe are limited to those phenomena that are within our light cone and there’s little reason to assume that what we see is representative of the universe as a whole.
Matt Webb’s utility allows you to calculate the light cone starting from your birth date (any date, actually) out to the first 50 light years. Here’s mine, apparently 12 Ophiuchi will be within my lightcone in about three months time.
Makes you wonder what else is out there doesn’t it?

Erdös is famous in mathematical circles for both his genius and his productivity. So much so that a low Erdös Number is a badge of honour amongst mathematicians. If you’ve got an Erdös Number of 1 then you collaborated with him directly; your number if 2 if you’ve collaborated with a collaborator, etc. The collaboration graph data is published if you’re interested. (I’ve been playing with it a bit recently).
The Man Who Loved Only Numbers is an excellent book, apart from the joy of discovery the wonderfully eccentric Erdös, the book covers a lot of interesting mathematical research and discoveries. Cantor’s work on infinite sets is amongst them.
The book provides some glimpses into how mathematical research is carried out, and the enthusiasm that mathematicians have for their subject. I wish I’d read this whilst I was at school, maybe then I’d have had more enthusiasm for the subject
Anyway if you enjoyed Mark’s posting then you’ll enjoy The Man Who Loved Only Numbers. It’s a great book.

You can get a taster for the contents of The Book of Pages from the authors website which has a number of other offerings which I’ve still to read through properly. Unfortunately the book’s actual website — bookofpages.com — seems to be offline, but happily the Wayback Machine has stashed away most of its contents. You can start browsing the archive from here.
The book is the story of Jiriki, a monk who is sent on a quest to find a book by the Abbot of his monastery. The quest takes Jiriki to the Metropolis, a future city full of advanced technology and robots. The story is really a fable, offering observations on modern life which, for me at least, invoked shades of James Gleick’s Faster. Only packaged in a more digestible format.
The illustrations are simple black-and-white line drawings. Each page is made up of a single illustration and two columns of text. The text providing narrative or commentary that reflect on the picture’s contents. The writing style is very readable, often wry, and I found myself rapidly immersed in Jiriki’s world and the odd cast of characters he encounters. The Magician; The Villian who steals numbers and stores them in mathematically-sealed magnetic pods; The Human Being Machine; and the Angel of Blame. There are six pages of the book available in the Wayback Machine archives for you to get a taster for yourselves.
Like all good stories the Book of Pages has a twist, only this one is introduced not at the end but 5/8ths of the way through. And it relates not to the story but to it’s medium of delivery: the book is actually a hypertext. I won’t spoil it any more than this.
A great book, and certainly worthy of a purchase, or maybe your local library has a copy too?
Personally I’m off down the newsagents as Debs has promised me she’ll buy me The Beano.

Have recently finished:

• Gibson’s Pattern Recognition: excellent as always. I flirted with this for a day or two as I knew it’d totally draw me in. I was right. The themes reminded me a bit of an Iain Banks novel towards the end, particularly the story behind “The Footage”. May post some musings about “Apophenia”
  at some point. See also: “Synesthesia”
• James Gleick’s Faster really does surf through “the acceleration of just about everything” and makes for some thought-provoking reading along the way. The phrase “we are surrounded by ephemera” particularly resonated.

I’ve just picked up The Meme Machine by Susan Blackmore. I’m going to be interested to see what she makes of the theory. I first encountered the term in one of Richard Dawkins’ books (I forget which). I’m hoping that Dawkins’ enthusiastic foreword isn’t indicative of Blackmore’s approach: I tend to find Dawkins to be too reductionist and I don’t think that viewpoint properly credits the power/utility/benefits of emergent properties in the phenotype. Mind you I’ve not kept up with his recent work so maybe his ideas have evolved along these lines.
Directly in the queue behind these are Small World, one of the plethora of popular science books on network theory that have cropped up recently, and Impossibility which just looked like an interesting read.
I also have Semiotics for Beginners (full-text available online, but I bought the book because I’m a Nice Man…and a luddite); The Pursuit of Oblivion; David Attenborough’s biography, “Life on Air“; and The Number Devil, which have all been languishing on the shelf for a while, so I’ve dusted their covers and promised them I’ll read them soon.
I’m also trying to decide whether I’ve got the energy to read A New Kind Of Science and/or The Structure of Evolutionary Theory. The latter is probably the more likely candidate as I’ve enjoyed Gould’s other books and my interests have recently been returning to biology, ecology, neurology, etc. The stuff that absorbed me during my first degree (started 13 years ago now, eek!). Unfortunately there’s not a great deal in computing (in general, not just books) thats exciting me at the moment. There’s a lot of “more, faster” but not a lot of “different”, if that makes any sense.
Book recommendations gratefully received. (See told you I was a luddite. Book recommendation engines? Pfah!)

I initially looked at XUL, and the Luxor toolkit but decided against them as the docs weren’t brilliant, and they were more complex than I wanted: I need something as simple as possible. I then picked up Thinlets and have been quite pleased. I’ve been building the FOAF-a-Matic Mark 2 using that framework and found it to quick and easy to use.
I’ve been teaching an introductory Java course for Bath University’s Community Course programme — I did one last term, and am half way through my second. As part of the preparation for this I took another look at Swing and found it was less horrid than I’d remembered. So I also ended building some code which I’ll release some day which is basically a Swing application framework, complete with a fledgling plugin system, and the Bean Scripting Framework for extra scripting goodness. I plan to add support for plugging in thinlets and probably applets as well. So the research has been is bearing fruit in various directions. And most importantly I’ve had some fun along the way. Until now anyway.
I came back to XUL once more via a rekindled interest in “smart browsing“. I’m interested in further automating the browser to do cool stuff ™ with all that metadata that web pages, blogs especially, are integrating these days. So, after poking around in my Mozilla installation a bit I decided it was time to find out exactly what XUL, XPCOM, XBL, etc were all about. Hence the book purchase.
Now, while the Creating Apps book has answered a lot of questions, its also raised a whole lot more. I’ve found it to be a rather infuriating read as it covers a lot of ground very quickly, so I’m left going back to the web, e.g. XUL Planet to get them answered. XUL is itself worthy of a book, even a Nutshell book, IMO.
The chapters on XUL Templates and Mozilla’s RDF support have left me on the one hand quite excited about the possibilities lurking beneath the covers of Mozilla, but on the other tearing my hair out with frustration as there are a lot of problems with the book. There are mistakes in the examples, diagrams are in correctly referenced, and in one case several pages were devoted to walking through an example of how to process some RDF data without actually showing the underlying data first.
There are corrections on the O’Reilly site, corrections on the Mozilla site, reader corrections in the per chapter comments, as well as bug reports. But no single unified place to check them all. I’m left running around double-checking everything. Even more frustratingly the example application, xFly, which has its own Mozilla project hasn’t been updated to include all the examples from the book! They are available as text files but you need to manually integrate them with the app (should you want to bother) or apply the corrections yourself. Not a good situation given the book was published September 2002.
This all lead me to conclude that the examples weren’t thoroughly tested, and had me questioning the wisdom of purchasing the book at all. But perhaps I’m being unfair as it may be that they’ve been trying to hit a moving target all along.
For example last night I spent several hours trying to apply sorting to a XUL tree element. The Creating Apps book uses the sort attribute in an example, but doesn’t explain it. I’ve since got that example running, but the sorting doesn’t actually work. Ooops. So I check the RDF docs on the Mozilla site and see that the XUL template primer has an example that uses the same syntax. Stumped again. The full XUL template reference, which is apparently outdated, has a “To Be Done” in the sorting section. Oh dear. So I check the XULPlanet tutorial and discover that uses a completely different syntax for the value of the sort attribute, and defines a couple of others to boot. This doesn’t work either. I even ended up fishing into the XUL for Mozilla itself to see how it did it (same as the XULPlanet tutorial). Still no joy. Googling doesn’t return any useful hits beyond the documents referenced above. This doesn’t bode well so I’m wondering whether to go any further at all.
But, if someone knows how to get sorting to work in a tree I’d appreciate some help.
And if anyone has built a complete working version of the xFly sample application from the Creating Apps book I’d appreciate a copy. And no doubt so would the authors.