21 May 2003

Codified Claptrap

One thing that has always annoyed me is the way that the mass-media constantly misinterprets or misconstrues science and scientific knowledge in order to bring sensationalism to their stories. In The Demon Haunted World, the late Carl Sagan describes how governments and public institutions have also often been guilty of this, such that, in his opinion, some societies have become increasingly scientifically illiterate.

This month's Sci. Am. has a short opinionated article in it by Michael Shermer, that I felt was worth mentioning, about this phenomena with respect to The Bible Code series.

The latest and most egregious example of the (mis)use of science in the (dis)service of religion is Michael Drosnin's Bible Code II, enjoying a lucrative ride on the New York Times best-seller list, as did the 1997 original.
[ Codified Claptrap -- Michael Shermer, Sci. Am., 228:6, p35, 2003. ]


Also, check out Feynman's classic Cargo Cult Science regarding this topic.

12 May 2003

Jackanory

Some books on my shelves that I have yet to read (maybe, perhaps):

I'm currently reading the wonderfully written and poignant The Child That Books Built by Francis Spufford. Expect a synopsis/review soon.

God, I wish I had more time to read. Mind you, not too much time though. ;)

9 May 2003

Lazarus

Where is Raed? is back! Woo-hoo! Yay!:)

Riffle shuffle

A riffle shuffle is when you shuffle a pack of playing cards such that the top half of the deck is interleaved with the bottom half. If you are able to do this perfectly, that is you can perfectly interleave the two halves of the deck of cards, then for a deck of 52 playing cards you would only need to perform 8 perfect riffle shuffles to put the deck back in the same order as you had originally started with! When Laurie told me this the other day, I couldn't believe it! Eight! So I wrote a little perl script to convince myself:

#!/usr/bin/perl
$ARGV[0] || die"usage: shuffle N\n"; $N=$ARGV[0]; for ($i=0;$i<$N;$i++) {$dA[$i]=$i+1; $dO[$i]=$dA[$i];} $k=0; do {$j=0; for ($i=0;$i<$N;$i=$i+2) {$dB[$i]=$dA[$j]; $j++;} for ($i=1;$i<$N;$i=$i+2) {$dB[$i]=$dA[$j]; $j++;} @dA=@dB; $t=1; for ($i=0;$i<$N;$i++) {if ($dA[$i]!=$dO[$i]) {$t=0;}} $k++;} while ($t==0); print $k."\n";


Sorry about the lack of comments and structure (gotta love perl ;), but the code above performs perfect riffle shuffles on an array of numbers (ie. a virtual deck of cards) until it ends up with an array that is the same as the original one (ie. the order of the shuffled deck is the same as the unshuffled one). You need to specify the number of cards in your virtual deck as an argument, and will be rewarded with the number of shuffles that were required.

And sure enough, if you specify 52 cards in your deck, then an answer of 8 shuffles is returned. Amazing! This is the same as if your deck was only composed of 18 cards. And furthermore, if your deck consisted of 54 cards (the normal 52 playing cards plus the 2 jokers), then you need to perform 52 perfect riffle shuffles to the deck in order to get back where you started!

There's a neat explanation on MathWorld (apparently what I've simulated above is an out-shuffle). I'm convinced that a group theoretic approach will yield a formula relating the number of shuffles required to the number of cards in a deck. The obsession goes on...

7 May 2003

Cambridge

Today I found myself in Cambridge for a workshop regarding grid applications in the UK (remind me to tell you all about my work one day). The meeting took place at the newly built Centre for Mathematical Sciences. The centre displays a strange yet appealing architecture consisting of a number of "pavilions" where each pavilion looked like a stylised pagoda made of glass and steel. These were splayed out around a lawn and common room (with an astroturf roof!) which was shaped like the wake of a boat. As strange as all this sounds, it actually worked. Here's an aerial photo:
Centre for Mathematical Sciences, Cambridge

After the meeting I met up with Fah. She made me walk what felt like the entire length of the River Cam, but it was fun catching up with her. Fah recently began a blog called Quasi-histrionic. "Histrionic" means excessively dramatic or emotional, and those of you who know Fah will know how it fits into her philosophy of life, the universe and everything. She's alot better at blogging than me so please excuse any copyright infringements on my blog. ;)

I don't know what it is about Cambridge in the sunshine. Could it be all those majestic and historic buildings, those prim lawns, the calm the comes from punting down the river, or that certain air of intellectual activity associated with the place. It's so wonderfully quaint and serene, I love it! Then again, maybe it's just that I've been in London for too long. :P