Topics (203k) Articles (205k) Users (298) Discussions (237) Comments (383) Files (715) New article
The Busy Beaver Competition: a historical survey by Pascal Michel by 
Ciro Santilli 40 Updated 2025-07-16
Ciro Santilli 40 Updated 2025-07-16We ust use the if mod notation definition as mentioned at: math.stackexchange.com/questions/4305972/what-exactly-is-a-collatz-like-problem/4773230#4773230
Course plan:
- Section "Programmer's model of quantum computers"
- look at a Qiskit hello world
- e.g. ours: qiskit/hello.py
- learn about quantum circuits.
- tensor product in quantum computing
- First we learn some quantum logic gates. This shows an alternative, and extremely important view of a quantum computer besides a matrix multiplication: as a circuit. Fundamental subsections:
- quantum algorithms
But what is quantum computing? by 3Blue1Brown
. Source. Ubuntu 23.04 install:
sudo apt install rbaseHello world:
R -e 'print("hello world")'As mentioned in True Genius: The Life and Science of John Bardeen page 224, the idea of symmetry breaking was a major motivation in Josephson's study of the Josephson effect.
Ciro Santilli invented this term, it refers to mechanisms in which you put an animal in a virtual world that the animal can control, and where you can measure the animal's outputs.
- MouseGoggles www.researchsquare.com/article/rs-3301474/v1 | twitter.com/hongyu_chang/status/1704910865583993236
- Fruit fly setup from Penn State: scitechdaily.com/secrets-of-fly-vision-for-rapid-flight-control-and-staggeringly-fast-reaction-speed/
So we see that the classification is quite simple, much like the classification of finite fields, and in strict opposition to the classification of finite simple groups (not to mention the 2023 lack of classification for non simple finite groups!)
Cross files references to IDs: yes. But no check by default for duplicates when doing automatic ID from title. Just automatically disambiguates with
-1, -2 suffixes, and links take the last one available.Source page splitting: splits at h2 by default. If configurable, likely always af fixed level?
Hello world documented at: bookdown.org/yihui/bookdown/get-started.html
Hello world on Ubuntu 23.04 after installing R:The build CLI comes from: stackoverflow.com/questions/50888871/how-to-use-rscript-command-line-tool-to-build-a-book-in-bookdown
sudo R -e 'install.packages("bookdown")'
git clone https://github.com/rstudio/bookdown-demo
cd bookdown-demo
Rscript -e 'bookdown::render_book("index.Rmd")'
xdg-open _book/index.htmlPart of the motivation letter required by some American universities explaining how amazing of a teacher you are, e.g.: wstein.org/job/Teaching/index.html
Welcome to my home page!
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!
Intro to OurBigBook
. Source. We have two killer features:
- 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-calculusArticles 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/derivativeVideo 2. OurBigBook Web topics demo. Source. - 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.
- to OurBigBook.com to get awesome multi-user features like topics and likes
- as HTML files to a static website, which you can host yourself for free on many external providers like GitHub Pages, and remain in full control
Figure 2. You can publish local OurBigBook lightweight markup files to either OurBigBook.com or as a static website.
Figure 3. Visual Studio Code extension installation.
Figure 5. . 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. 
- Infinitely deep tables of contents:
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