Fear of flying

Joel Gilmore at illuminating science asks an interesting question about the test flight of SpaceShipOne that’s been in the news:

Oh, and a question of scruples for you all: The X-Prize requires a ship with one pilot and two passengers, but the passengers on this flight were replaced by ballast (as allowed by the rules.) If you’d been offered one of those passenger seats for today’s flight, would you have taken it? I have to say that I would have, despite the obvious risks with what the commentators called “test flight in its purest form.” In a room of three physicists, we had two votes for yes and one for no – what would you do?

I’d be tempted, but I’m pretty sure that, when push came to shove, I wouldn’t be up for the risk. Admittedly, if I’d been the person developing the rocket, I might well be interested in a flight. But just to be an invited passenger, nah. I’d rather wait for the “debugged” version.

Categorized as General


I’m about 100 pages into Roger Penrose’s huge (1000+ pages) new book, The Road to Reality: A Complete Guide to the Laws of the Universe. Marketed to the general public, it promises to give an overview – with equations! – of our current understanding of the laws of the Universe.

It’s not exactly a typical popular science book, containing detailed discussions of topics like the Cauchy-Riemann equations, differential forms, fibre bundles, gauge theories, and so on, with Penrose going into quite some detail.

I’m not sure how much the book’s purported audience – the general public – will get out of it. It’s rather detailed in places, with lots of equations, and definitions of complicated and abstract mathematical objects. I’m perhaps somewhat too close to the subject matter to trust my own judgement on the extent to which he succeeds in spinning an interesting and coherent story for the lay reader.

Even with that caveat, though, I greatly admire Penrose’s chutzpah in making the attempt to tell this story in a way that is widely accessible.

I’m certainly finding the book interesting. Even in the early parts of the book, which cover (relatively) elementary stuff, I’m picking up useful tidbits of knowledge and perspectives. I suspect many of my millions… er, tens… of readers will enjoy it also.

Here’s the link to amazon.co.uk. The book doesn’t appear to be out yet in the US.

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Comment spam

I am fairly often asked what I get out of running this blog.

Probably the thing I enjoy the most is the comments. It’s not suprising but is nonetheless true that it’s incredibly rewarding to get thoughtful commentary on topics you care about, from people halfway round the world (or even just down the hall). And I’ve had more of that than I ever expected.

There is, however, a downside to the comments. I started getting comment spam shortly after starting this blog. The idea is that spammers put “comments” on the blog, usually something trivial like “Good reading!” together with a URL for their product, in order to improve their Google pagerank. Just as fast, I try to delete the comments.

While less odious than the nitwit who spammed the Olympic diving (via DFL), it’s gotten old deleting a dozen comments a day, even using Jay Allen’s terrific spam blacklist plugin.

As a result, I’ll now close off further commenting on posts after a month or so, unless the comments are still active. Old comments will still be viewable, it just won’t be possible to add to them.

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I’m a real sucker for hearing what makes other people tick, especially when those people really love what they do. Here’s a good essay in this vein by cartoonist Hugh MacLeod on how to be creative.

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David Deutsch’s weblog

David Deutsch, who proposed the first concrete model of a quantum computer and the first quantum algorithm (among many other things), now has a weblog.

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More Google coolness

Via Musings, the best geek cool advertising campaign ever (I’ve modified the format of the post slightly):

Most of the billboards around the UT campus feature alcohol and/or scantily-clad women. But one austere black-on-white billboard on Guadelupe has intrigued me as I drive past it on my way home from work:

www. { first 10-digit prime found in the consecutive digits of e } .com

If you find the aforementioned prime (I, personally, was surprised at how far out in the decimal expansion of e one has to go to find it), and visit the corresponding website, you are greeted with a second puzzle

f (1)=7182818284
f (2)=8182845904
f (3)=8747135266
f (4)=7427466391
f (5)= __________

and you’re told to visit a second website, using “Bobsyouruncle” as a Username and the value of f (5) as a password.

When you get there, you’re greeted with an offer to submit your resumé … to Google.

One thing we learned while building Google is that it’s easier to find what you’re looking for if it comes looking for you. What we’re looking for are the best engineers in the world. And here you are.

As you can imagine, we get many, many resumes every day, so we developed this little process to increase the signal to noise ratio. … You’ll find links to more information about our efforts below, but before you get immersed in machine learning and genetic algorithms, please send your resume to us at …

Now that’s a sexy advertising campaign.

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International Perceptions

When travelling overseas, especially in the US, I am often asked about Australian and international attitudes towards Bush. This interesting Reuters article documents the results of some recent global polling. Apparently Bush gets 20% of the world vote, to Kerry’s 46%.

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Automating the Zoo

One of my favourite internet resources is Scott Aaronson’s Complexity Zoo, a compendium of pretty much everything that is known about computational complexity classes. I’m a physicist, and don’t have a huge need for this kind of thing, but even so, I find it surprisingly useful, surprisingly often. When I want to know something about complexity classes, the Zoo is the second best resource I know of. Of course, the best resource is to ask Scott (or another suitably inclined computer scientist) directly.

But such people aren’t always around. An interesting idea for a project that came up in conversation with Tereza Tušarová and Dan Kenigsberg last week is to produce a front end for the Complexity Zoo: a natural language interface, ideally capable of automated reasoning, and perhaps even of producing non-trivial proofs, or telling you interesting things (“yes, the inclusion you propose is possible, but the polynomial hierachy would collapse”). Unfortunately, I don’t have time to do this, but just thought I’d mention it here, in case anyone interested in symbolic mathematics were looking for a fun project.

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Via Illuminating Science, Google now does unit conversions. Google for “convert 17 pounds to kilograms”, and back it’ll come. More ambitiously, “convert 3 furlongs per fortnight to parsecs per second”, and back it’ll come.

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