On the Shoulders of Giants: Selections from the Principle of Relativity, by Albert Einstein, edited, with commentary, by Stephen Hawking
If you slow down a photon to v=0, will all of it's energy convert into mass? e=mc^2. m=e/c^2. If I had my cheat-sheet from physics class, I could replace those symbols with values and calculate how much mass exactly that would be. Photons have a very small mass (and no volume at all); the speed of light is very, very fast; and a little mass, when converted into energy, creates a big boom. I imagine the mass gained would not be very much at all. Of course, this is assuming you could slow down a photon. According to the special theory of relativity, light travels at the same speed regardless of the observer's inertial frame. Hmmm. Time can warp depending on the observer's inertial frame, but the speed of light, which is measured in distance traveled over units of time, is always constant. Cool. Albert really was crazy.
American Recovery and Reinvestment Act of 2009
I haven't advanced far enough to comment on this one other than to say it must be the most boring piece I have ever read--and I still have four hundred pages to go.
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