The more familiar transitions we are familiar with like liquid water into solid water happen at constant temperature.
However, other types of phase transitions we are less familiar in our daily lives happen across a continuum of such "state variables", notably:
Arline Greenbaum by Ciro Santilli 40 Updated 2025-07-16
Feynman's first wife, previously his local-high school-days darling. Feynman was like an reversed Stephen Hawking: he married his wife knowing that she had a serious illness, while Hawking's wife married him knowing that as well. Except that in Feynman's case, the disease outcome (tuberculosis) was much more uncertain, and she tragically died in 1945 much earlier while Feynman was at Los Alamos Laboratory, while Hawking, despite his decline, lived much longer.
Feynman first noticed Arline on the beaches on the region of his home in Far Rockaway, in the Queens, New York, near Long Beach. She lived a bit further inland in Cedarhurst. Arline was beautiful and boys competed for her, but Richard persisted, stalking her at an after-school social league sponsored by the local Synagogue and joining an art class she went to, until he eventually won it out. The region was highly Jewish, and both were from Jewish families, as also suggested by their family names.
Reading about her death e.g. at Genius: Richard Feynman and Modern Physics by James Gleick (1994) is a major tearjerker, it's just too horrible. The book mentions on chapter "The Last Springtime" that at last, during the last months of her life, after much hesitation, they did fuck in the sanatorium Arline where was staying at in Albuquerque, the nearest major city to Los Alamos (154 km), despite the risk of Feynman being infected, which would be particularly serious given that Feynman would be in constant contact with students and possibly infect others as part of his career as a researcher/teacher. Feynman would visit her on weekends by bus, and stay in Los Alamos during the week.
Arline finally died on June 16th 1945, exactly one month before the Trinity nuclear test was carried out. The atomic bombings of Hiroshima and Nagasaki were a little later on 6 and 9 of August 1945.
On one of his last trips to Oak Ridge town late 1945, after her death, Feynman walked past a shop window and saw a pretty dress. He thought to himself, "Arline would have liked that", and the reminder made him cry for the first time after Arline's death.
It is even sadder to think that the first antibiotics for tuberculosis, streptomycin, finished its first major clinical trial at around 1948, not long after her death.
Figure 1. . Source. TODO date, location, original source.
Figure 2. . Source. TODO date, location, original source. Seems like in a hospital.
Video 1.
Abacus scene from the film Infinity (1996)
Source.
The film suggests that Feynman and Arline fucked a lot before the final Los Alamos fuck, that fuck story from book being only "fuck after tuberculosis diagnosis", after which they had to slow it down a bit.
This is likely true given how long they had been together for at that point. Ciro Santilli is such a pure soul for not having thought that! They were not very conservative at all those two.
Also their wedding got slowed down because there was a clause in Feynman's scholarship at Princeton University stating that the recipient could not be married, those were different times altogether.
Feynman became a terrible womanizer after his first wife Arline Greenbaum died, involving himself with several married women, and leading to at least two abortions according to Genius: Richard Feynman and Modern Physics by James Gleick (1994).
Ciro Santilli likes to think that he is quite liberal and not a strict follower of Christian morals, but this one shocked him slightly even. Feynman could be a God, but he could also be a dick sometimes.
One particular case that stuck to Ciro Santilli's mind, partly because he is Brazilian, is when Feynman was in Brazil, he had a girlfriend called Clotilde that called him "Ricardinho", which means "Little Richard"; -inho is a diminutive suffix in Portuguese, and also indicates affection. At some point he even promised to take her back to the United States, but didn't in the end, and instead came back and married his second wife in marriage that soon failed.
Richard's third and final wife, Gweneth Howarth, seemed a good match for him though. When they started courting, she made it very clear that Feynman should decide if he wanted her or not soon, because she had other options available and being actively tested. Fight fire with fire.
Joan Feynman by Ciro Santilli 40 Updated 2025-07-16
Video 1.
My brother, Richard: How he came to be so smart interview with Joan Feynman by Web of Stories (2019)
Source. Ah, shame to see Joan so old. Some good stories. The tiles game thing was not mentioned in Genius: Richard Feynman and Modern Physics by James Gleick (1994) I think.
From Surely You're Joking, Mr. Feynman chapter O Americano, Outra Vez!:
The people from the airlines were somewhat bored with their lives, strangely enough, and at night they would often go to bars to drink. I liked them all, and in order to be sociable, I would go with them to the bar to have a few drinks, several nights a week.
One day, about 3:30 in the afternoon, I was walking along the sidewalk opposite the beach at Copacabana past a bar. I suddenly got this treMENdous, strong feeling: "That's just what I want; that'll fit just right. I'd just love to have a drink right now!"
I started to walk into the bar, and I suddenly thought to myself, "Wait a minute! It's the middle of the afternoon. There's nobody here, There's no social reason to drink. Why do you have such a terribly strong feeling that you have to have a drink?" - and I got scared.
I never drank ever again, since then. I suppose I really wasn't in any danger, because I found it very easy to stop. But that strong feeling that I didn't understand frightened me. You see, I get such fun out of thinking that I don't want to destroy this most pleasant machine that makes life such a big kick. It's the same reason that, later on, I was reluctant to try experiments with LSD in spite of my curiosity about hallucinations.
One notable drug early teens Ciro consumed was Magic: The Gathering, see also: Section "Magic: The Gathering is addictive".
Cycle notation by Ciro Santilli 40 Updated 2025-07-16
A concise to describe a specific permutation.
A permutation group can then be described in terms of the generating set of a group of specific elements given in cycle notation.
E.g. en.wikipedia.org/w/index.php?title=Mathieu_group&oldid=1034060469#Permutation_groups mentions that the Mathieu group is generated by three elements:
  • (0123456789a)
  • (0b)(1a)(25)(37)(48)(69)
  • (26a7)(3945)
which feels quite compact for a simple group with 95040 elements, doesn't it!
Dietterich Labs by Ciro Santilli 40 Updated 2025-07-16
Unfortunately the channel is too obsessed with mathematical detail (which it does amazingly), and does not give enough examples/application/intuition, which is what would be useful to most people, thus falling too much on the hardcore side of the missing link between basic and advanced.
This channel does have on merit however: compared to other university courses, it is much more direct, which might mean that you get to something interesting before you got bored to death, Section "You can learn more from older students than from faculty" comes to mind.
Videos generally involves short talks + a detailed read-through of a pre-prepared PDF. Dietterich has refused however giving the PDF or LaTeX source as of 2020 on comments unfortunately... what a wasted opportunity for society. TODO find the comment. Sam, if you ever Google yourself to this page, let's make a collab on OurBigBook.com and fucking change education forever man.
Video 1.
The Ultimate Goal Of My YouTube Channel by Dietterich Labs (2020)
Source. In this video Dietterich gives his ideal for the channel. Notably, he describes how the few experimental videos he has managed to make were done in a opportunistic way from experiments that were happening around him. This resonated with Ciro Santilli's ideas from videos of all key physics experiments.
Video 2.
Sam Dietterich interview by Dietterich Labs (2022)
Source. TODO find patience to watch and summarize key points.
Video 3.
The Sting Of Soft Corruption: My College Experience by Dietterich Labs
. Source. Academia is broken video.
ViaScience by Ciro Santilli 40 Updated 2025-07-16
Those guys are really good, Ciro Santilli especially enjoyed their quantum mechanics playlist: www.youtube.com/playlist?list=PL193BC0532FE7B02C
The quantum electrodynamics one was a bit too slow paced for Ciro unfortunately, too much groundwork and too little results.
Accompanying website with a tiny little bit of code: viascience.org/what.html
TODO: authors and their affiliation.
Videos licensed as CC BY-SA, those guys are so good.
These videos can give some geometric insight and do have their value.
And when things get "mathy", it sticks to a more qualitative view which may not be enough.
Very over the top with sexy demons and angels making appearances, and has some classic aesthetic artistic value :-)

Pinned article: Introduction to the OurBigBook Project

Welcome to the OurBigBook Project! Our goal is to create the perfect publishing platform for STEM subjects, and get university-level students to write the best free STEM tutorials ever.
Everyone is welcome to create an account and play with the site: ourbigbook.com/go/register. We belive that students themselves can write amazing tutorials, but teachers are welcome too. You can write about anything you want, it doesn't have to be STEM or even educational. Silly test content is very welcome and you won't be penalized in any way. Just keep it legal!
We have two killer features:
  1. topics: topics group articles by different users with the same title, e.g. here is the topic for the "Fundamental Theorem of Calculus" ourbigbook.com/go/topic/fundamental-theorem-of-calculus
    Articles of different users are sorted by upvote within each article page. This feature is a bit like:
    • a Wikipedia where each user can have their own version of each article
    • a Q&A website like Stack Overflow, where multiple people can give their views on a given topic, and the best ones are sorted by upvote. Except you don't need to wait for someone to ask first, and any topic goes, no matter how narrow or broad
    This feature makes it possible for readers to find better explanations of any topic created by other writers. And it allows writers to create an explanation in a place that readers might actually find it.
    Figure 1.
    Screenshot of the "Derivative" topic page
    . View it live at: ourbigbook.com/go/topic/derivative
  2. local editing: you can store all your personal knowledge base content locally in a plaintext markup format that can be edited locally and published either:
    This way you can be sure that even if OurBigBook.com were to go down one day (which we have no plans to do as it is quite cheap to host!), your content will still be perfectly readable as a static site.
    Figure 2.
    You can publish local OurBigBook lightweight markup files to either https://OurBigBook.com or as a static website
    .
    Figure 3.
    Visual Studio Code extension installation
    .
    Figure 4.
    Visual Studio Code extension tree navigation
    .
    Figure 5.
    Web editor
    . You can also edit articles on the Web editor without installing anything locally.
    Video 3.
    Edit locally and publish demo
    . Source. This shows editing OurBigBook Markup and publishing it using the Visual Studio Code extension.
    Video 4.
    OurBigBook Visual Studio Code extension editing and navigation demo
    . Source.
  3. https://raw.githubusercontent.com/ourbigbook/ourbigbook-media/master/feature/x/hilbert-space-arrow.png
  4. Infinitely deep tables of contents:
    Figure 6.
    Dynamic article tree with infinitely deep table of contents
    .
    Descendant pages can also show up as toplevel e.g.: ourbigbook.com/cirosantilli/chordate-subclade
All our software is open source and hosted at: github.com/ourbigbook/ourbigbook
Further documentation can be found at: docs.ourbigbook.com
Feel free to reach our to us for any help or suggestions: docs.ourbigbook.com/#contact