Surely You're Joking, Mr. Feynman chapter O Americano, Outra Vez! Updated 2025-03-28 +Created 1970-01-01
In this chapter Richard Feynman talks about his experiences in Brazil.
"O Americano, Outra Vez!" means "The American, once again!" in Portuguese, which is what one of the samba school boss exclaimed when Feynman was not playing well his instrument, the frigideira, during a rehearsal.
Feynman really enjoyed Brazil's (and notably Rio's) stereotypical "take it easy and enjoy life" attitude.
Surely You're Joking, Mr. Feynman chapter Alfred Nobel's Other Mistake Updated 2025-03-28 +Created 1970-01-01
Key quote that names the chapter:
My friend Matt Sands was once going to write a book to be called Alfred Nobel's Other Mistake.
An IBM made/pushed term, but that matches Ciro Santilli's general view of how we should move forward AGI.
Ciro's motivation/push for this can be seen e.g. at: Ciro's 2D reinforcement learning games.
No 2x2 examples please. I'm talking about large matrices that would be used in supercomputers.
If we didn't have GUIs, terminal multiplexers would be our desktop environments. E.g. they handle stuff like:It is a thing of beauty.
- window switching
- copy pasting across windows
- screen locking
- clock on the status bar (same one that holds tabs)
Two ways to see it:
- a ring where inverses exist
- a field where multiplication is not necessarily commutative
One of the most nerve wrecking movies ever made. Until they decide to rescue their colleague from jail, then it just becomes too surreal.
This software feels amazing. You can really start composing very quickly, lots of features, good keyboard shortcuts.
GPL, and there's a backing company that makes money with an online and mobile version of it.
Ubuntu 20.04: sound preview worked, first hat that trailing Contra-like sound artifacts (like
spd-say), but then it went away?Feels like a lot of effort was put into usability, including keyboard shortcuts by default, seems like a powerful and easy to start using software to compose music!
Glissando: yes: musescore.org/en/handbook/arpeggios-and-glissandi
One important quantum mechanics experiment, which using quantum effects explain the dependency of specific heat capacity on temperature, an effect which is not present in the Dulong-Petit law.
This is the solid-state analogue to the black-body radiation problem. It is also therefore a quantum mechanics-specific phenomenon.
Multivariate polynomial where each term has degree 2, e.g.:is a quadratic form because each term has degree 2:but e.g.:is not because the term has degree 3.
More generally for any number of variables it can be written as:
There is a 1-to-1 relationship between quadratic forms and symmetric bilinear forms. In matrix representation, this can be written as:where contains each of the variabes of the form, e.g. for 2 variables:
Strictly speaking, the associated bilinear form would not need to be a symmetric bilinear form, at least for the real numbers or complex numbers which are commutative. E.g.:But that same matrix could also be written in symmetric form as:so why not I guess, its simpler/more restricted.
The Principles of Quantum Mechanics by Paul Dirac revised fourth edition (1967) Updated 2025-03-28 +Created 1970-01-01
Change sign if you swap two input values.
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