Ising model Updated 2025-07-16
Toy model of matter that exhibits phase transition in dimension 2 and greater. It does not provide numerically exact results by itself, but can serve as a tool to theorize existing and new phase transitions.
Each point in the lattice has two possible states: TODO insert image.
As mentioned at: stanford.edu/~jeffjar/statmech/intro4.html some systems which can be seen as modelled by it include:
Also has some funky relations to renormalization TODO.
Video 1.
The Ising Model in Python by Mr. P Solver
. Source. The dude is crushing it on a Jupyter Notebook.
Islam character Updated 2025-07-16
Islam has some really nice things in it.
The way it was perverted to be used as a tool for terrorism by some is a great tragedy.
Ciro Santilli especially appreciates the ideas of
Isomers suggest that atoms exist Updated 2025-07-16
Subtle is the Lord by Abraham Pais (1982) page 85:
However, it became increasingly difficult in chemical circles to deny the reality of molecules after 1874, the year in which Jacobus Henricus van't Hoff and Joseph Achille Le Bel independently explained the isomerism of certain organic substances in terms of stereochemical properties of carbon compounds.
so it is quite cool to see that organic chemistry is one of the things that pushed atomic theory forward. Because when you start to observe that isomers has different characteristics, despite identical proportions of atoms, this is really hard to explain without talking about the relative positions of the atoms within molecules!
TODO: is there anything even more precise that points to atoms in stereoisomers besides just the "two isomers with different properties" thing?
Isometry group Updated 2025-07-16
The group of all transformations that preserve some bilinear form, notable examples:
ISO SQL TRIGGER syntax Updated 2025-07-16
TODO what is the standard compliant syntax?
SQLite does not support SQL stored procedures at all, so maybe that's why they can't be standard compliant here: stackoverflow.com/questions/3335162/creating-stored-procedure-in-sqlite
SQL:1999 11.38 covers "Trigger definition". The Abstract syntax tree starts with the CREATE TRIGGER and ends in:
<triggered SQL statement> ::=
  <SQL procedure statement>
This is defined at 13.5 "SQL procedure statement", but that is humongous and I'm not sure what it is at all.
Isothermal means "at fixed temperature".
This is to contrast with the more well established polymerase chain reaction, which requires heating and cooling the sample several times.
The obvious advantage of isothermal methods is that their machinery can be simpler and cheaper, and the process can happen faster, since you don't have to do through heating and cooling cycles.
Iterative in-order Updated 2025-07-16
This is a bit harder than iterative pre-order: now we have to check if there is a left or right element or not:
  • (START) push current
  • if there is left:
    • move left
  • else:
    • (ELSE) pop
    • visit
    • if there is right
      • move right
      • GOTO START
    • else:
      • GOTO ELSE
The control flow can be slightly simplified if we allow NULLs: www.geeksforgeeks.org/inorder-tree-traversal-without-recursion/
Jami (software) Updated 2025-07-16
Ciro Santilli worked on it for a brief time in 2016, when it was still called Ring, before he got fired. :-)
The people were quite nice and the project idea is fine, Ciro hopes they succeed.
Video 1.
Ring - Peer to peer network for real time communication - FOSDEM 2016 by Ciro Santilli
. Source.
Japanese Brazilians Updated 2025-07-16
Japanese Brazilians are either model children, or they're good for nothings. There is no intermediate.
In the 2010's/2020's, many people got excited about getting children in to electronics with cheap devboards, notably with Raspberry Pi and Arduino.
While there is some potential in that, Ciro Santilli always felt that this is very difficult to do, while also keeping his sacred principle of backward design in mind.
The reason for this is that "everyone" already has much more powerful computers at hand: their laptops/desktops and even mobile phones as of the 2020s. Except perhaps if you are thing specifically about poor countries.
Therefore, the advantage using such devboards for doing something that could useful must come from either:
You don't need to understand the from first principles derivation of every single phenomena.
And most important of all: you should not start learning phenomena by reading the from first principles derivation.
Instead, you should see what happens in experiments, and how matches some known formula (which hopefully has been derived from first principles).
Only open the boxes (understand from first principles derivation) if the need is felt!
E.g.:
Physics is all about predicting the future. If you can predict the future with an end result, that's already predicting the future, and valid.
Jáchymov Updated 2025-07-16
"Joachimsthal" is the German for it. Note how it is just near the modern frontier between Germany and the Czech Republic.
It is from ore of this mine that Uranium and Radium were discovered.
Apparently the region was a silver mining center:
Starting in the late Middle Ages, pitchblende was extracted from the Habsburg silver mines in Joachimsthal, Bohemia (now Jáchymov in the Czech Republic), and was used as a coloring agent in the local glassmaking industry
Jackdaw Playing With Water Updated 2025-07-16
Considered one of the 10 famous Chaozhou music pieces TODO list.
Was also adapted by Liu Baoshan (1937-1997) as a pipa song. Ciro Santilli prefers the pipa version.
Video 1.
Jackdaw Playing With Water performed by Xu Lingzi on the guzheng at the Wiener Musikverein
. Source.
Video 2.
Jackdaw Playing With Water performed by Lin Shicheng on the pipa
. Source.
Jacquard machine Updated 2025-07-16
Video 1.
A Jacquard loom in action by NationalMuseumsScotland (2016)
Source. The lack of audio is unsettling!

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