Blog » 2006 » January

25 Jan 2006

Extraordinary measurements

Filed under: Technology and science — paulcook @ 7:06 pm

In the news today is the discovery of a planet about fives times the mass of Earth, orbiting a star 20 000 light years away from Earth.

That’s just amazing. Never mind the implications for the search for life, or any of that — the actual measurement is amazing. A quick back of-the-envelope calculation shows that an equivalent measurement would be observing something the width of a human hair, end on — about 0.05mm thick. It’s not easy seeing that with the naked eye more than about a tenth of a metre away, never mind on the moon.

Meanwhile, the people at LIGO are trying to measure changes in the path length of a ray of light, caused by passing gravitational waves, of less than a thousandth of the width of an atomic nucleus.

And the Large Hadron Collider, under construction near Geneva, will collide thousands or millions of protons a second, and track almost all of the vast numbers of particles each collision creates. We typically talk about atoms in groups of about 10^23 particles, but here we’re talking about tracking each individual particle.

And perhaps most amazing to me, we can make meaningful statements about the whole universe a tiny fraction of a second after the Big Bang, based on a few observations from a single planet in a single place in the universe, at essentially a single point in time in the universe’s evolution.

There are some really smart people out there.

16 Jan 2006

Christmas letter 2005

Filed under: Caltech News (emails), Personal — paulcook @ 11:44 pm

Note: this post will be boring for regular readers of this blog. It’s my attempt at a “Christmas letter”, for email distribution. But for completeness I’m posting it here too!


I’m starting to write this in Idaho, as a guest of my apartment mate, Mike Adams. Time and funds mean that this year I’m spending Christmas in the USA – and Mike’s family has been generous enough to host me for a week, and even to buy me some Christmas presents! Most people I’ve mentioned it to have been surprised to hear that I was heading to Idaho, as it is not renowned as a tourist destination. But it has been an excellent week of relaxation, spent reading, watching movies, eating and walking in the surrounding hills. I was even able to instruct a Christmas dinner party of 15 in the correct way of pulling Christmas crackers (complete with coloured paper crowns)!

When do we learn?

Filed under: Personal, Politics and philosophy — paulcook @ 11:25 pm

Education and learning are strange beasts. At school and university, people seldom understand even close to everything, and forget most of what they did understand soon after the final exam. But yet we trust doctors to prescribe correctly; professionals to know their jobs; or professors and teaching assistants to know what they are talking about. Where does this knowledge come from??