physical attacks

The first of Richard Feynman's 1964 Cornell Messenger Lectures, The Character of Physical Law, focusing on the law of gravitation. Feynman builds up from planetary motion to the nature of physical laws.

Part 2 of Richard Feynman's Messenger Lectures at Cornell, The Character of Physical Law, on the relation of mathematics to physics. He explains why understanding nature requires mathematics.

The first of Richard Feynman's 1964 Messenger Lectures at Cornell, 'The Character of Physical Law', covering the law of gravitation. Feynman traces the history from Kepler and Newton to the universality of the inverse-square law. The recording is an older one with weak audio.

A short clip of Richard Feynman on the difference between merely knowing how to reason mathematically and understanding why physical theories work. He discusses holding multiple equivalent ideas and guessing new laws.

A clip of Richard Feynman contrasting the Greek and Babylonian traditions of mathematical reasoning. It compares the axiomatic approach of mathematicians with how physicists use mathematics.

Robert Sapolsky's lecture on how the body's stress response, evolved for short-term physical emergencies, harms long-term health when triggered by psychological stressors. It was given as the inaugural Fenton-Rhodes Lecture.

Jean-Marc Jancovici lectures at ENS Paris on whether energy use, jobs and growth can all be preserved. He argues for a physical approach to economics, since resource depletion and climate limits make perpetual GDP growth unrealistic.

Admiral Grace Hopper holds up a length of wire to show how far light travels in a nanosecond, about 11.8 inches. She explains how she made the idea concrete to people who could not picture a billionth of a second.