E = mc2(1-v2/c2)-½

I've been following a vast series of maths lectures over the last 6 months or so from the physicist Leonard Susskind. This is a guy who can argue the toss with Stephen Hawking and then go teach a class of continuing education students. It's the recordings of his CE classes that I'm watching.

Susskind has a such a likable personality and easy style he can often lull you into a false sense of security, and then he'll snap you out of it with a jerk. I wish I'd had a teacher like him 25 years ago when I still could do maths properly (practice, Holroyd, practice - yes I know).

Fast forward this lecture to about 1h 15min and watch him derive Einstein's famous E=mc² with such consummate skill it's like he's stating the bleedin' obvious. His play with 'c' the speed of light, is almost comedy and his correction by (1-v²/c²)^-½ is the bit non-physicists always forget (but that's the most important bit 'coz it tells you it's impossible to accelerate a mass to the speed of light*).

Lecture 6 | Modern Physics: Special Relativity (Stanford)

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If you are daft like me and want to follow the whole thing, start with his course on classical mechanics:
Lecture 1 | Modern Physics: Classical Mechanics (Stanford)
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* I can't think how to html 'one divided by square root' except to raise it to minus the half power