Angela Collier on The Story Behind Bose-Einstein Statistics and Fermi-Dirac Statistics

It's really interesting, ... Bose's manuscript was rejected so he just sent it to Einstein. Fortunately Einstein read it and thought it was OK, ...

I had some comments:

... then I watched the colophon:

4:00 So can astrophysicists separate out what part of that spectral broadening is due to thermal motion and what part to different isotopes? Or doesn't that really matter for astrophysics? [Update 31:57 so could you make three videos describing spectral broadening?] [Update: 45:16 or four videos?]

24:09 The simplest explanation of the Stern-Gerlach experiment is always one where we pretend we can measure the spin of a free electron. As far as I know there is no spin experiment that can do that. They always measure it indirectly with an atom of silver or something, and make some assumptions about the measurable effects on the trajectory of the whole system of electron shells and the nucleus as it passes through the apparatus. I remember that the argument connecting the torque experienced by the whole atom with the electron spin was quite tricky, and I never actually managed to convince myself of it. But I had an exam I had to pass, so, ... I passed the exam, but I don't understand electron spin or how we can distinguish electrons one from another if they are not bound in some whole system like an atom. 

See The discovery of the electron spin by S.A. Goudsmit:

That is the way the history looks and it is a somewhat curious history. Who, precisely, should get credit for it? Such things are not possible without also giving credit to all other people who have contributed. But one aspect stands out which is of particular importance for young people. First: you need not be a genius to make an important contribution to physics because, I do admit, the electron spin is an important contribution. That I know now, then we did not know, but now I do. They all told me so.

Then I want to say one more thing: even if you make a minor contribution, if it is not important, then this gives an enormous satisfaction. Therefore I do believe that one should not always aspire to tackle what is most important, but try to have fun working in physics and obtain results.

Subscribe to Angela Collier.

Gabriele Carcassi has been looking into this in the Assumptions of Physics project. It's all over my head though:

See also Curt Jaimungal Interview With Urs Schreiber.
 

Subscribe to Gabriele Carcassi.

Comments

Post a Comment

Popular posts from this blog

Steven Johnson - So You Think You Know How to Take Derivatives?

Image
A derivative is linearisation, and differential calculus is essentially linear algebra, ...  See  Freya Holmér - Why Can't You Multiply Vectors?  and  Freya Holmér on Continuity of Splines . See also the MIT OCW page:  Matrix Calculus For Machine Learning And Beyond  (Alan Edelman, Steven G. Johnson) Subscribe to The Julia Programming Language . Alan Edelman talking about expressing mathematics as computer code. The idea is that you can use computer languages to communicate mathematical ideas precisely to other people. See my comments about functional programming languages here:  https://prooftoys.org/ian-grant/hm/ Subscribe to TEDx Talks .
Read more

Hitachi HD44780U LCD Display Fonts

Image
I finally got the bit-mapped fonts from the Hitachi "1602" display :  Here's some JavaScript: const HD44780U01ASCII=[ [],[],[],[],[],[],[],[],[],[],[],[],[],[],[],[], [],[],[],[],[],[],[],[],[],[],[],[],[],[],[],[], [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, ], [4, 4, 4, 4, 0, 0, 4, 0, 0, 0, ], [10, 10, 10, 0, 0, 0, 0, 0, 0, 0, ], [10, 10, 31, 10, 31, 10, 10, 0, 0, 0, ], [4, 15, 20, 14, 5, 30, 4, 0, 0, 0, ], [24, 25, 2, 4, 8, 19, 3, 0, 0, 0, ], [12, 18, 20, 8, 21, 18, 13, 0, 0, 0, ], [12, 4, 8, 0, 0, 0, 0, 0, 0, 0, ], [2, 4, 8, 8, 8, 4, 2, 0, 0, 0, ], [8, 4, 2, 2, 2, 4, 8, 0, 0, 0, ], [0, 4, 21, 14, 21, 4, 0, 0, 0, 0, ], [0, 4, 4, 31, 4, 4, 0, 0, 0, 0, ], [0, 0, 0, 0, 12, 4, 8, 0, 0, 0, ], [0, 0, 0, 31, 0, 0, 0, 0, 0, 0, ], [0, 0, 0, 0, 0, 12, 12, 0, 0, 0, ], [0, 1, 2, 4, 8, 16, 0, 0, 0, 0, ], [14, 17, 19, 21, 25, 17, 14, 0, 0, 0, ], [4, 12, 4, 4, 4, 4, 14, 0, 0, 0, ], [14, 17, 1, 2, 4, 8, 31, 0, 0, 0, ], [31, 2, 4, 2, 1, 17, 14, 0, 0, 0, ], [2, 6, 10, 18, 31, 2, 2, 0, 0,...
Read more

Welsh Republic Podcast Talking With Kars Collective on Armenia Azerbaijan Conflict

Image
  In the last 30 hours, Azerbaijan has blocked the Berdzor Corridor (the only route in and out of Artsakh), established a military police presence, threatened to shoot any flying object leaving the capital Stepanakert, and has now cut the gas supply. This is now a blockage. — Kars Collective (Կարսի Կոլեկտիվ) (@KarsCollective) December 13, 2022 Subscribe to Welsh Republic Podcast .
Read more