Built on Facts

Archives for May, 2010

Before we get to the heart of yesterday’s quiz, let me briefly define solid angle for those who may not be familiar with it. Regular angles are measured in degrees or radians, and solid angles are to angles as square meters are to meters. Solid angle is more or less angular area, and is measured…

Solar Heat & Thermodynamics

Pop quiz! The picture below is a solar power facility wherein light from the sun is collected by mirrors and focused onto the top of a collecting tower. Fluid within the tower is heated by this light and the hot fluid is used to generate power. We won’t care about that in this quiz though;…

Sunday Function

You’re a member of the French Resistance in the height of WWII. You’re part of a network of resistance members who have to work with other resistance members they’ve never met before. For instance, an agent from Paris might have to meet up with an agent in Normandy to work together on sabotage before the…

Happy Birthday!

I can’t let this week go by without mentioning that it is – officially – the 50th birthday of the invention of the laser. Officially, anyway. On the 16th of May 1960, Theodore H. Maiman produced the first working optical laser. There was actually recently a huge slap-fight in the letters to the editor of…

The Shuttle on a Diet

Space Shuttle mission STS-132 is currently orbiting over our heads. It’s scheduled to land a week from now. After that, there’s two more launches and that will be that for the program. At that point the US will officially be out of the business of launching people into orbit, and there’s not a lot of…

Sunday Function

Consider this not-so-difficult sum: It consists of just a string of fractions up to whichever N you happen to choose. Add them up, and you certainly and unambiguously have a number. If you chose to stop at N = 10, you’d find that f(10) = 1627/2520, which is about 0.645635. If you chose to stop…

Sole Survivor

CNN has a headline up: Fate or Fluke: Air crash sole survivors. ON the homepage itself the banner reads “Fate or Physics?” (CNN) — Some will see it as divine intervention, others a simple quirk of fate, fortune or physics, but one boy’s cheating of death in an air crash in Libya this week adds…

The Theory of Theory

I recently learned about a great blog by S.C. Kavassalis of the University of Toronto called The Language of Bad Physics. She discusses, among other things, the way language is used in physics. She’s got an interesting piece on the use of the word “theory”. This is always a hot area of discussion, but in…

This semester I took a course on quantum optics. I’m an AMO guy and quantum optics is one of our department’s particular strengths, so it was both a very useful class and a pleasure to take. One of the graded requirements of the class is to write a paper from a list of quantum optics…

Sunday Function

It’s been a while since we’ve done a Sunday Function, so let’s get back into the swing of things with a weird one. This is Thomae’s function, and using Wikipedia’s conveniently typeset definition: If you’re new to the concept of rational and irrational numbers, it’s pretty simple. A number is rational if it can be…