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Feynman’s Derivation of the Schrödinger Equation

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Re: Feynman’s Derivation of the Schrödinger Equation

#5

Post by wyager »

Where did we get that [Schrödinger's equation] from? It's not possible to derive it from anything you know. It came out of the mind of Schrödinger. -The Feynman Lectures on Physics

For anyone who wants to study quantum mechanics and has a math background, I strongly recommend Shankar's quantum textbook. It has the most rigorous, clear, and correct derivations I have seen thus far, starting with vector spaces and moving to physical systems only after a hundred or so pages.

Re: Feynman’s Derivation of the Schrödinger Equation

#6

Post by kurthr »

I find that often reading a scientist's dissertation will often tell you something about how they approach the rest of their research. Somewhere I actually have a paper copy of Feynman's Thesis under Wheeler, which covers exactly this material. He was clearly enamored of Lagrangian formulations quite early (I didn't know that it was due to a High School teacher).

You can find this actual thesis on-line at CERN: http://cds.cern.ch/record/101498/files/Thesis-1942-Feynman.p...

It's short at 74 book pages, and relatively readable.

Re: Feynman’s Derivation of the Schrödinger Equation

#7

Post by danharaj »

wyager wrote: post #5

Where did we get that [Schrödinger's equation] from? It's not possible to derive it from anything you know. It came out of the mind of Schrödinger. -The Feynman Lectures on Physics For anyone who wants to study quantum mechanics and has a math background, I strongly recommend Shankar's quantum textbook. It has the most rigorous, clear, and correct derivations I have seen thus far, starting with vector spaces and movi…

Have you ever read Lectures on Quantum Mechanics for Mathematics Students or Quantum Mechanics for Mathematicians? I'd like to know how Shankar's book sits in the space of QM textbooks.

Re: Feynman’s Derivation of the Schrödinger Equation

#9

Post by 77pt77 »

wyager wrote: post #5

Where did we get that [Schrödinger's equation] from? It's not possible to derive it from anything you know. It came out of the mind of Schrödinger. -The Feynman Lectures on Physics For anyone who wants to study quantum mechanics and has a math background, I strongly recommend Shankar's quantum textbook. It has the most rigorous, clear, and correct derivations I have seen thus far, starting with vector spaces and movi…

For the love of God, do not use Shankar!

The book is just down right atrocious. The fact that it became almost standard in American universities speaks more of the power of networking than anything else. Shankar's book is anything but rigorous, quite on the contrary.

There are so many good QM books:

For an absolute beginner I'd recommend David Griffiths

Dirac's is very readable

Sakurai's is very good though a bit advanced

Whatever you do, it's difficult to go wrong by not using Shankar's

Re: Feynman’s Derivation of the Schrödinger Equation

#10

Post by 77pt77 »

danharaj wrote: post #7
wyager wrote: post #5

Where did we get that [Schrödinger's equation] from? It's not possible to derive it from anything you know. It came out of the mind of Schrödinger. -The Feynman Lectures on Physics For anyone who wants to study quantum mechanics and has a math background, I strongly recommend Shankar's quantum textbook. It has the most rigorous, clear, and correct derivations I have seen thus far, starting with vector spaces and movi…

Have you ever read Lectures on Quantum Mechanics for Mathematics Students or Quantum Mechanics for Mathematicians ? I'd like to know how Shankar's book sits in the space of QM textbooks.

Shankar is all round a very practical book to pass quals, very poorly structured, highly pretentious by dealing with say parth integrals with grassman variables but doing an awful job at basic stuff such as adding angular momentum.

If you've got a math background I'd recommended you skip Shankar even more vehemently than I usually do.

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