Second quantization by Ciro Santilli 40 Updated 2025-07-16
Second quantization also appears to be useful not only for relativistic quantum mechanics, but also for condensed matter physics. The reason is that the basis idea is to use the number occupation basis. This basis is:
Bibliography:
This one might actually be understandable! It is what Richard Feynman starts to explain at: Richard Feynman Quantum Electrodynamics Lecture at University of Auckland (1979).
The difficulty is then proving that the total probability remains at 1, and maybe causality is hard too.
The path integral formulation can be seen as a generalization of the double-slit experiment to infinitely many slits.
Feynman first stared working it out for non-relativistic quantum mechanics, with the relativistic goal in mind, and only later on he attained the relativistic goal.
TODO why intuitively did he take that approach? Likely is makes it easier to add special relativity.
This approach more directly suggests the idea that quantum particles take all possible paths.
Renormalization by Ciro Santilli 40 Updated 2025-07-16
Video 1.
The Biggest Ideas in the Universe | 11. Renormalization by Sean Carroll (2020)
Source. Gives a very quick and high level overview of renormalization. It is not enough to satisfy Ciro Santilli as usual for other Sean Carroll videos, but it goes some way.
Coulomb gauge by Ciro Santilli 40 Updated 2025-07-16
Alternative to the Lorentz gauge, but less used in general as it is not as nice for relativity invariance.
Last mile problem by Ciro Santilli 40 Updated 2025-07-16
The exact same problem appears over and over, e.g.:
Ciro Santilli also identified knowledge version of this problem: the missing link between basic and advanced.
en.wikipedia.org/wiki/Logarithm_of_a_matrix#Existence mentions it always exists for all invertible complex matrices. But the real condition is more complicated. Notable counter example: -1 cannot be reached by any real .
The Lie algebra exponential covering problem can be seen as a generalized version of this problem, because
Bert Hubert by Ciro Santilli 40 Updated 2025-07-16
Co-founder of PowerDNS, an open source dNS implementation.
Homepage: berthub.eu/ says:
I sometimes contribute to science, I care a lot about Europe, innovation, biology & health
.
All stuff Ciro cares about too! Cool dude! In particular Ciro loved his quote of I should have loved biology.
He's writing a fun-sounding book about molecular biology as of 2022: berthub.eu/dna-book. Appears to be closed source though. Ciro wonders if he really needs to sell the book for money after all those years though, rather than just publishing it online for free.
Looking at Bert just brings the Dutch Golden Age, and more in particular Antonie van Leeuwenhoek to mind. Epic.
Video 1.
How life is Digital by Bert Hubert (2021)
Source. Just a "boring" overview of the central dogma of molecular biology ;-)
Eli Benderski by Ciro Santilli 40 Updated 2025-07-16
Amazing systems programming tutorials. Whenever you Google a hard topic, his blog comes up.
Also has many great contributions on Stack Overflow: stackoverflow.com/users/8206/eli-bendersky
As of 2016, Eli worked at Google (reference). TODO before that, I had found his earlier info previously but lost it.
Eli focuses mostly on compiler toolchains.
Fabrice Bellard by Ciro Santilli 40 Updated 2025-07-16
Creator of QEMU and FFmpeg, both of which Ciro Santilli deeply respects. And a bunch other random stuff.
What is shocking about Fabrice this is that both are insanely important software that Ciro Santilli really likes, and both seem to be completely unrelated subjects!
Google made billions on top of this dude:
At last but not least, Fabrice also studied in the same school that Ciro Santilli studied in France, École Polytechnique.
It is a shame that he keeps such a low profile, there are no videos of him on the web, and he declines interviews.
Another surprising fact is that Fabrice has not worked for the "Big Tech Companies" as far as can be publicly seen, but rather mostly on smaller companies that he co-founded: www.quora.com/Computer-Programmers/Computer-Programmers-Where-is-Fabrice-Bellard-employed
And he's also into some completely random projcts unsurprisingly:
Figure 1. . Source. At a restaurant with the author apparently. Plus Miguel De Icaza who was in Paris for some conference, which they all presumably attended.
Figure 2. . There are no in-focus images of Fabrice on the Internet.
Aaron Swartz by Ciro Santilli 40 Updated 2025-07-16
Aaron, Ciro Santilli will complete your quest to make eduction free. Just legally this time, with the and with the Creative Commons license you helped to create.
Ciro likes how The Internet's Own Boy (2014) explains how Aaron felt like high school was bullshit, and that he could learn whatever he wanted from books, which is one of Ciro's key feelings.
It also mentions how he was a natural teacher from a very early age.
Sandy Maguire by Ciro Santilli 40 Updated 2025-07-16
Lots of similar ideologies to Ciro Santilli, love it:
Other interesting points:
He's a Haskell person.

Pinned article: Introduction to the OurBigBook Project

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