Mass Matters

Well, only four weeks and change behind us in this course, and… the class (see here and here) is ready to understand this wonderful equation:

the schwarzschild solution

and all that it implies. What is it? It encodes the shape of spacetime around a spherical blob of mass of total mass M. No, don’t worry too much about the details, since this is not a lecture about General Relativity….. it is just nice (I hope) every now and again to get a look at the sorts of things we use in our day to day work. This “warped” spacetime encodes what we interpret as the gravitational field (in the old Newtonian language) due to a spherical (or, to a good approximation, almost spherical) mass. Like the sun, or the earth, or that tennis ball in the corner there*. It is an exact solution […] Click to continue reading this post

Randall on Colbert

lisa randall on colbertMy first time sitting down to watch this show in a while and, bizarrely enough, there’s a colleague on the telly! Well, I think that perhaps Lisa was trying a little bit too hard in one or two places to get the physics out. On Colbert, I think you just have to go with the flow and the comedy! But she got quite a bit out in the short time she had…

My favourite bit:

Randall: “Like…the fact that Einstein has taught us that spacetime can be curved or warped…”

Colbert: “Don’t patronize me, I know that…”

[…] Click to continue reading this post

Science Debate 2008 – Closer to Reality

So Chris and Sheril have announced the next step in the journey to a real debate about science issues of note that intersect with the current political sphere. And they’ve come a long way in a short time! Here’s some of what they said in a recent post:

ScienceDebate2008 is now co-sponsored by the American Association for the Advancement of Science, the National Academies, and the Council on Competitiveness. We were looking at venues, and finally settled on an offer from the Philadelphia-based Franklin Institute–named, of course, after one of this country’s first and greatest scientists. We can’t think of a more appropriate venue.

And guess what?! They’ve actually invited the candidates: Hillary Clinton, Mike Huckabee, John McCain, and Barack Obama.

So the next step is to get the event (they suggest April 18, 2008) taken seriously by the […] Click to continue reading this post

A Delicious Fractal

romanesque cauliflower

A small Romanesque Cauliflower. (Click for larger view.)

Imagine my delight when I spotted this lovely piece of edible mathematics in the Hollywood Farmer’s Market this morning. The stall has several of them of many sizes (this was a very little one) and of several colours. Wonderful. If you don’t know what I mean when I talk about the mathematics, or use the term fractal, look it up. There are several things of note, among which are the wonderful spiral structures that you can […] Click to continue reading this post

Friday Night Wanderings

It was one of those Friday nights when I was in the mood to get out of the house, but not entirely sure what to get out to. “Out” was more important than “where”, you see. Wanted to do a bit of thinking and to relax and let the heavy week of too many meetings fall away from my shoulders.

In the end, I did a combination of things. After my mood, followed by my at charlie o’s. John Beasley, Nolan Shaheed, Dave Carpenter, Roy McCurdytrajectory, turned away from Pasadena (where I was planning to see Persepolis, as was my original plan – I’ll do it later… really want to see that film) at about 10:30pm I arrived in the Valley and hung out at Charlie O’s which is one of the more happening of the neighbourhoody jazz clubs in LA. (Sadly, in this context, “happening” by LA late night standards means that there’s more than about nine people present.)

There’s always something on each night and you can just walk in and sit at the bar to […] Click to continue reading this post

Equivalence

equivalence principle

Well, Tuesday was a big day in class. We reached a landmark – the introduction of one of my very favourite thoughts of the 20th Century: the Equivalence Principle. This is the realization of Einstein’s that there’s something profoundly odd about Newtonian mechanics and Newtonian gravity that hints at something deeper.

Quick reminder from high school (just two formulae, please bear with me): You know […] Click to continue reading this post

Just Checking on New York

Readers in New York… Uh… Are you ok? Leave a comment to let me know that you and the city are still there, ok?

cloverfield posterJust got back from seeing Cloverfield. Quite well done, on balance. They do a great job of mocking up what it would be like to be just an ordinary citizen during your standard city-under-attack scenario. Routine falls apart, people are scared, fighter jets scream by low and fast overhead, there’s only fragments of information about what’s happening, and you find yourself wondering why on earth we build these tall buildings anyway… Yes, the filmmakers did a very […] Click to continue reading this post