An unexpected thing on Del Mar Blvd

I was driving along Del Mar a day or two ago, just past Lake Ave near Caltech. It was dusk, and car headlights were just coming on. As I pulled up to the light, a huge bakkie (pickup truck) with raised suspension and huge tires pulled up right behind me, with its headlights on. I don’t think the brights were on, but the height of the truck put its headlights at exactly the right height to shine directly into my eyes, via every rear-view mirror I had.

Naturally, this was annoying. For a while I leant forward, till my neck got tired. Then I sat back, but with my hand raised between me and the rear-view mirror on the windscreen, thinking idle nasty thoughts about people who feel the need to turn perfectly normal cars into monstrosities.

But after a few seconds the strangest thing happened: the truck turned off its headlights. Since it was dusk, the only possible explanation was that the driver had seen my hand, worked out the problem, and turned off his/her lights. And in that instant my idle annoyance became a lot more complicated.

By being so obvious about the thing, I had turned a minor annoyance of mine into something so significant that the other driver decided to turn off the headlights. Was I really justified in doing so? Sure, it was the design of the truck that had created the problem in the first place, but what if the driver was only borrowing it? Or had realised only after buying it the implications for everyone else on the road? Since the driver was clearly aware of the effect it had on others, was he/she driving it out of necessity only? Ironically enough, getting what I most wanted had suddenly left me unsure that it was fair to be wanting it in the first place.

And what will the other driver do now? Since I was in a normal car, she/he will now be aware of the discomfit caused every time his/her truck is behind a car. Driving without headlights is clearly not possible, so will the driver be cringing each time a light turns red with some cars in front of him/her?

Such a simple act, so many questions!

Extraordinary measurements

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.

When do we learn?

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??
Continue reading “When do we learn?”