{title2=theorized 1975}
{title2=observed 1978}
{wiki}

Quantum version of the <Hall effect>.

As you increase the <magnetic field>, you can see the <Hall resistance> increase, but it does so in discrete steps.

\Image[https://upload.wikimedia.org/wikipedia/commons/3/38/Rhoxy.jpg]
{title=<Hall resistance> as a function of the applied <magnetic field> showing the <Quantum Hall effect>}
{description=As we can see, the blue line of the <Hall resistance>  TODO material, temperature, etc. It is unclear if this is just }

Gotta understand this because the name sounds cool. Maybe also because it is used to define the <fucking> <ampere in the 2019 redefinition of the SI base units>.

At least the experiment description itself is easy to understand. The hard part is the physical theory behind.

TODO <videos of all key physics experiments>[experiment video].

The effect can be separated into two modes:
* <Integer quantum Hall effect>: easier to explain from first principles
* <Fractional quantum Hall effect>: harder to explain from first principles
  * <Fractional quantum Hall effect for \nu = 1 m>: <1998 Nobel Prize in Physics>
  * <Fractional quantum Hall effect for \nu \ne 1 m>: one of the most important <unsolved physics problems> as of 2023


Quantum Hall effect

{c}

* <Suikoden>{child}, <Ciro Santilli> played that one when he was a teenager! That section has some remarks of interest.


Water Margin adaptation

Organic compound

Chinese punctuation

{c}
{title2=2nd Pitaka}
{title2=Teachings}
{wiki}


Sutta Piṭaka

TODO, including why the Schrodinger equation is not.


The Dirac equation is consistent with special relativity

{wiki}

Since <rat> and <mouse> are not scientifically specific names, we'll just use them interchangeably.

When one specific species is implied, we will mean <Mus musculus> by default.


French politician

{c}

https://www.mentava.com/
\Q[Mentava's software-based daily tutor gets students on track for college-level math and computer science before high school.]


Mentava

Human immortalised cell line

Transcription

{c}
{tag=Messier object}
{title2=2.5 Mly}
{title2=3.44 m}
{wiki}

= Messier 31
{c}
{synonym}
{title2}

First proper <galaxies nearest the Milky Way>[nearest galaxy to the Milky Way]. Everything in the middle in the <Local group> is either a satellite of the Milky Way or Andromeda.

Many Andromeda satellite galaxies are simply numbered Andromeda II, Andromeda III and so on.

As described on Wikipedia, the observational history of Andromeda is fascinating. Little by little, people noticed that it had a different nature to many other objects observed on the sky, and the hypothesis that there are other galaxies like ours grew in force.

Part of our fascination with Andromeda is due to how similar in size and shape and close it is to the Milky Way.

It is clearly the only thing so large and so close.

Andromeda is, without a doubt, our sister galaxy.

One can't help but wonder if there is some <alien> looking back at us when we are looking at them through our <Telescope>.

Andromeda is also the furthest object from <Earth> that can be seen with the naked eye.https://www.relativelyinteresting.com/10-astronomical-targets-new-telescope/{ref} Not surprising, as it literally shines with the strength of a trillion suns!

\Image[https://web.archive.org/web/20220713191240im_/https://cdn.spacetelescope.org/archives/images/thumb700x/heic1502a.jpg]
{title=Highest resolution image of Andromeda as of 2015, taken by Hubble}
{description=Source also says it was the highest resolution image every released by the Hubble. This goes to show how fascinated people are by Andromeda. And there is good reason for it.}
{source=https://esahubble.org/images/heic1502a/}

\Video[https://www.youtube.com/watch?v=3mWSp3YnuLI]
{title=Andromeda Shun from <Saint Seiya> performing his Nebula Chain attack}
{description=The original <Japanese (language)> music actually says "Nebula Chain" in English. The <Andromeda Galaxy> is shown on the back, the chain appears to go all the way to it and back towards the evil guys' head. Not very <relativistic>, but so be it.}

\Video[https://youtu.be/pXcRKoxTPVg?t=973]
{title=<Andromeda Galaxy> with only a Camera, Lens, & Tripod by Nebula Photos (2020)}
{description=Good job! Gives a good idea of the low end approach.}


Andromeda Galaxy

{wiki}

= Atomic bomb
{synonym}

= Nuclear bomb
{synonym}

\Image[https://upload.wikimedia.org/wikipedia/commons/thumb/0/0f/Plutonium_ring.jpg/505px-Plutonium_ring.jpg]
{title=A weapons-grade ring of electrorefined plutonium, typical of the rings refined at Los Alamos and sent to Rocky Flats for fabrication}
{description=The ring has a purity of 99.96%, weighs 5.3 kg, and is approx 11 cm in diameter. It is enough plutonium for one bomb core. Which city shall we blow up today?}

<Ciro Santilli> is mildly obsessed by nuclear reactions, because they are so <Ciro Santilli's self perceived creative personality>[quirky]. How can a little ball destroy a city? How can putting too much of it together produce criticality and kill people like in the https://en.wikipedia.org/wiki/Demon_core[Slotin accident] or the https://www.youtube.com/watch?v=ZWomuWd7-to[Tokaimura criticality accident]. It is <mind blowing> really.

<Uranium> vs <plutonium>: <uranium vs plutonium Quora answer by Ciro Santilli>{full}.

More fun nuclear stuff to watch:
* <Dr. Strangelove (1964)>
* https://en.wikipedia.org/wiki/Chernobyl_(miniseries)[]
* <The World Of Enrico Fermi by Harvard Project Physics (1970)>
* https://en.wikipedia.org/wiki/Fat_Man_and_Little_Boy[Fat Man and Little Boy (1987)] shows a possibly reasonably realistic of the history of the development of the <Trinity (nuclear test)>

\Video[https://www.youtube.com/watch?v=1E3sFfnAUQs]
{title=Tour of a nuclear misile silo from the 60's by Arizona Highways TV (2019)}

\Video[https://www.youtube.com/watch?v=8uIPQBOCJ64]
{title=The Ultimate Guide to Nuclear Weapons by hypohystericalhistory (2022)}
{description=
Good overall summary. Some interesting points:
* https://youtu.be/8uIPQBOCJ64?t=2946 talks about the difference between <tactical and strategic nuclear weapons>
* https://youtu.be/8uIPQBOCJ64?t=3291 mentions <variable yield> devices, this is the main new thing <Ciro Santilli> learned from this video
* https://youtu.be/8uIPQBOCJ64?t=3416 discusses if a <strategic nuclear weapon> usage would inevitably lead to <tactical nuclear weapon> escalation. It then mentions one case in which a possibly comparable escalation didn't happen: the abstainance of using <chemical weapon> during <World War II>.
}


Nuclear weapon

Phosphate

Boston Dynamics

{wiki}

A branch of <mathematics> that attempts to prove stuff about <computers>.

Unfortunately, all <software engineers> already know the answer to the useful theorems though (except perhaps notably for <cryptography>), e.g. all programmers obviously know that iehter <p versus NP problem>[P != NP] or that this is <independence (mathematical logic)>[unprovable or some other "for all practical purposes practice P != NP"], even though they don't have proof.

And 99% of their time, software engineers are not dealing with mathematically formulatable problems anyways, which is sad.

The only useful "computer science" subset every programmer ever needs to know is:
* for arrays: <dynamic array> vs <linked list>
* for <associative array>: <binary search tree> vs <hash table>. See also https://stackoverflow.com/questions/6147242/heap-vs-binary-search-tree-bst/29548834\#29548834[Heap vs Binary Search Tree (BST)]. No need to understand the algorithmic details of the hash function, the <NSA> has already done that for you.
* don't use https://en.wikipedia.org/wiki/Bubble_sort[Bubble sort] for sorting
* you can't parse HTML with regular expressions: https://stackoverflow.com/questions/1732348/regex-match-open-tags-except-xhtml-self-contained-tags/1732454\#1732454[] because of <formal language theory>

Funnily, due to the <formalization of mathematics>, <mathematics> can be seen as a branch of computer science, just like computer science can be seen as a branch of Mathematics!


Title	Author	Created	Updated
Quantum Hall effect	Ciro Santilli 32	1970-01-01	1970-01-01
Water Margin adaptation	Ciro Santilli 32	1970-01-01	1970-01-01
Organic compound	Ciro Santilli 32	1970-01-01	1970-01-01
Chinese punctuation	Ciro Santilli 32	1970-01-01	1970-01-01
Sutta Piṭaka	Ciro Santilli 32	1970-01-01	1970-01-01
The Dirac equation is consistent with special relativity	Ciro Santilli 32	1970-01-01	1970-01-01
Rat	Ciro Santilli 32	1970-01-01	1970-01-01
French politician	Ciro Santilli 32	1970-01-01	1970-01-01
Mentava	Ciro Santilli 32	1970-01-01	1970-01-01
Human immortalised cell line	Ciro Santilli 32	1970-01-01	1970-01-01
Transcription	Ciro Santilli 32	1970-01-01	1970-01-01
Andromeda Galaxy	Ciro Santilli 32	1970-01-01	1970-01-01
Nuclear weapon	Ciro Santilli 32	1970-01-01	1970-01-01
Phosphate	Ciro Santilli 32	1970-01-01	1970-01-01
Boston Dynamics	Ciro Santilli 32	1970-01-01	1970-01-01
Computer science	Ciro Santilli 32	1970-01-01	1970-01-01
Interpretations of quantum mechanics	Ciro Santilli 32	1970-01-01	1970-01-01
Particle decay	Ciro Santilli 32	1970-01-01	1970-01-01
Wealth inequality	Ciro Santilli 32	1970-01-01	1970-01-01
Extant	Ciro Santilli 32	1970-01-01	1970-01-01

Ciro Santilli (@cirosantilli, 32)