Richard Feynman Lecture on Quantum Electrodynamics: QED. 2/8

Part 3:http://www.youtube.com/watch?v=S9PNp-UK-Vo
Richard Feynman gives us a lecture on Quantum electrodynamcis, the theory of photons and electron interactions which incorporates his unique view of the fundamental processes that create it. one of the 3 winners of the 1965 Nobel prize in Physics for his work, Feynman is was an expert on quantum mechanics and developed the Path Integral formulation of Relativistic Quantum mechanics, used in Quantum Field Theory, interpreted the Born series of scattering amplitudes as vertices and Green's function propagators in his famous diagrams, the Feynman Diagrams, and also worked on the fundamental excitations in Liquid Helium leading to a correct model describing superfluidity using phonons, maxons and rotons to describe the various excitation curves.
other fields of work include the Feynman-Hellmann Theorem, which can relate the derivative of the total energy of any system to the expectation value of the derivative of the Hamiltonian under a single parameter, e.g volume.
he also worked on the Rogers Commission report during the investigation of the 1986 Space Shuttle Challenger disaster, where Feynman famously demonstrated how the Booster Rocket O-rings, which are elastic sealing joints, became less resilient and subject to seal failures at ice-cold temperatures by immersing a sample of the material in a glass of ice water- his high intelligence and independant way of looking at the world often made him "a real pain" in the eyes of other, less skilled, Commission members.
Feynman's own investigation reveals a disconnect between NASA's engineers and executives that was far more striking than he expected. His interviews of NASA's high-ranking managers revealed startling misunderstandings of elementary concepts, such as safety proceedures.
Although Feynman got plenty of media coverage due to him being on the Commission, he was often told to stay quiet about NASA's more sinister secrets and tactics in space exploration.

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Science & Technology

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• Feynman
• Quantum
• electrodynamics
• Field
• Theory
• Mechanics
• photons
• electrons
• electromagnetism
• nuclear
• forces
• fundamental
• physics
• lectures
• QED
• elementary
• particles
• chemistry

[sfsoma]

Thanks for uploading this. I have been looking for a complete and good quality copy of this lecture. Professor Fenynman  is one of my favorites.

[MuonRay]

@sfsoma Thanks. I plan to upload Lectures 2 and 3 in this lecture series on QED- they're by far the best lectures on the subject, in terms of recorded lectures, I have seen so far. Only Leonard Susskind from the Standford University lectures seems to explain it with the same merit, which is very hard to do- books on the subject are often complicated enough as it is, but worth reading especially on things like the Born series, which was Feynman's influence for those particle diagrams of his.

[cormisterio]

@texkeks there is no god

[texkeks]

Science is god, and its prophet is Feynman.

[system0system0]

why is he gone.

[ClamCrunchy]

There is no God and Dirac is his prophet.

[mkarnerfors]

The funny part is that today we can(!) measure the distance to the moon in such a way that it is relevant to differ between whether we're measuring from the top of his head or from his feet.

The accuracy when measuring the distance to the moon today is actually better than the distance from the top and bottom of his eyebrows.

[QuantumChance]

Why do they laugh at 0:45 ?

mathematical ignorance?

[TwistedLemniscate]

@mrbrugh nature observing that it's trying to explain its own existence...

[haz464]

@mixxmexx no

[mixxmexx]

@cormisterio is there a devil?

[skitt1z1]

@cormisterio I think he was being poetic...

[CamiloSanchez1979]

The theory is right in centimeters when the atom is 100 km....this was 79, imagine where we're at now.

[mrbrugh]

nature trying to explain its own existence....