Ciro Santilli @cirosantilli 37 

The process that imports proteins encoded in the nuclear DNA and made in the cytosol into the mitochondria.

The term is mentioned e.g. in this article: www.nature.com/articles/nrm2959.

Power, Sex, Suicide by Nick Lane (2006) suggests that proteins are somehow tagged with extra amino acids for this.

MNIST database Updated 2025-07-16

70,000 28x28 grayscale (1 byte per pixel) images of hand-written digits 0-9, i.e. 10 categories. 60k are considered training data, 10k are considered for test data.

This is THE "OG" computer vision dataset.

Playing with it is the de-facto computer vision hello world.

It was on this dataset that Yann LeCun made great progress with the LeNet model. Running LeNet on MNIST has to be the most classic computer vision thing ever. See e.g. activatedgeek/LeNet-5 for a minimal and modern PyTorch educational implementation.

But it is important to note that as of the 2010's, the benchmark had become too easy for many applications. It is perhaps fair to say that the next big dataset revolution of the same importance was with ImageNet.

The dataset could be downloaded from yann.lecun.com/exdb/mnist/ but as of March 2025 it was down and seems to have broken from time to time randomly, so Wayback Machine to the rescue:

wget \
 https://web.archive.org/web/20120828222752/http://yann.lecun.com/exdb/mnist/train-images-idx3-ubyte.gz \
 https://web.archive.org/web/20120828182504/http://yann.lecun.com/exdb/mnist/train-labels-idx1-ubyte.gz \
 https://web.archive.org/web/20240323235739/http://yann.lecun.com/exdb/mnist/t10k-images-idx3-ubyte.gz \
 https://web.archive.org/web/20240328174015/http://yann.lecun.com/exdb/mnist/t10k-labels-idx1-ubyte.gz

but doing so is kind of pointless as both files use some crazy single-file custom binary format to store all images and labels. OMG!

OK-ish data explorer: knowyourdata-tfds.withgoogle.com/#tab=STATS&dataset=mnist

Momentum operator Updated 2025-07-16

One dimension in position representation:

\overset{p}{^} = - i ℏ \frac{\partial}{\partial x}

(1)

In three dimensions In position representation, we define it by using the gradient, and so we see that

\overset{p}{^} = - i ℏ \frac{\partial}{\partial x}

(2)

Position and Momentum from Wavefunctions by Faculty of Khan (2018)

Source. Proves in detail why the momentum operator is

\frac{\partial}{\partial x}

. The starting point is determining the time derivative of the expectation value of the position operator.

Monotreme Updated 2025-07-16

The weirdest mammal clade: they lay fucking eggs. Only 5 known species alive as of 2020.

Eggs are basal: they simply didn't evolve out of what other reptiles do. From which we conclude that milk came before eggs stopped.

So this is the most basal subclade of mammals.

Etymology: means "single hole" in Greek, because like other reptiles it has a single hole for shit, pee and fucking: the cloaca.

Moon Updated 2025-07-16

Most important superconductor material Updated 2025-07-16

As of 2023 the most important ones economicaly were:

Nb-Ti: the most widely used one. Used e.g. to create the magnetic fields of the Large Hadron Collider Up to 15 T.
Nb-Sn: more expensive than Nb-Ti, but can reach up to 30 T.

The main application is magnetic resonance imaging. Both of these are have to be Liquid helium, i.e. they are not "high-temperature superconductor" which is a pain. One big strength they have is that they are metallic, and therefore can made into wires, which is crucial to be able to make electromagnetic coils out of them.

Music teenager Ciro Santilli liked to listen to Updated 2025-07-16

Lower teens, before discovering more hardcore stuff that is more genial and adult-venerable:

So a base mix of what you migth expect from a regular male teenager born in 1989 Brazil.

OK, Ciro still comes back to those from time to time, he confesses. Nostalgia, nostalgia.

The following are also adult venerable though :-)

Killing In the Name by Rage Against The Machine (1992)

Source.

As mentioned on Wikipedia, it has only 8 lines of lyrics.

And the most satisfying "Ugh"s ever recorded on tape. Rap rock perfectly describes the genre.

And no, the opening sentence "Some of those that work forces" is not understandable: ell.stackexchange.com/questions/262444/what-is-the-meaning-of-the-phrase-that-work-forces-in-rage-against-the-machine

MySQL Updated 2025-07-16

sudo mysql

works on Ubuntu 20.10.

Create user for further logins without sudo askubuntu.com/questions/915585/how-to-login-mysql-shell-when-mysql-have-no-password/1325689#1325689:

sudo mysql -e "CREATE USER $USER"

Run command from CLI stackoverflow.com/questions/1602904/how-do-you-run-a-single-query-through-mysql-from-the-command-line

mysql -e 'SHOW DATABASES'

Create test user with password:

sudo mysql -e 'CREATE USER user0 IDENTIFIED WITH mysql_native_password BY "a"'
sudo mysql -e 'GRANT ALL PRIVILEGES ON database_name.* TO "user0"'

and login as that user:

mysql -u user0 -p

mysql -u user0 -pmypassword

The IDENTIFIED WITH mysql_native_password part is to overcome "Client does not support authentication protocol requested by server" when connecting from Node.js.

List users:

sudo mysql -e 'SELECT * FROM mysql.user'

View permissions for each user on each DB: serverfault.com/questions/263868/how-to-know-all-the-users-that-can-access-a-database-mysql

sudo mysql -e 'SELECT * FROM mysql.db'

List databases:

sudo mysql -e 'SHOW DATABASES'

Create database:

sudo mysql -e 'CREATE DATABASE mydb0'

Destroy database:

sudo mysql -e 'DROP DATABASE mydb0'

Show tables in database:

sudo mysql -e 'SHOW TABLES' mydb0

or:

sudo mysql -e 'SHOW TABLES FROM mydb0'

Neil Fernandez Updated 2025-07-16

www.thetimes.co.uk/article/the-everyday-genius-pxsq5c50kt9:

Article likely written by him: www.theguardian.com/commentisfree/2010/feb/22/home-schooling-register-families

“Especially my father. He was doing most of it and he is a savoury, strong character. He has strong beliefs about the world and in himself, and he was helping me a lot, even when I was at university as an undergraduate.”
An only child, Arran was born in 1995 in Glasgow, where his parents were studying at the time. His father has Spanish lineage, having a great grandfather who was a sailor who moved from Spain to St Vincent in the Carribean. A son later left the islands for the UK where he married an English woman. Arran’s mother is Norwegian.
“My father was writing and my mother is an economist. They both worked from home which also made things easier,” Arran says.

A bit like what Ciro Santilli feels about himself!

One of the articles says his father has a PhD. TODO where did he work? What's his PhD on? Photo: www.topfoto.co.uk/asset/1357880/

Neil, a political economist, attended state and private schools in Hampshire but was also taught for a period at home by his mother.

It’s strange because for most people maths is a real turn-off, yet maths is all about patterns and children of two or three love patterns. It just shows that schools are doing something seriously wrong.”

Network switch Updated 2025-07-16

A switch is a box with a bunch of Ethernet wires coming into it:

+--------------------+
| +-+  +-+  +-+  +-+ |
| |1|  |2|  |3|  |4| |
| +-+  +-+  +-+  +-+ |
+--------------------+

Except that it doesn't have to be Ethernet, e.g. it would also be a Wi-Fi.

What the switch does is:

an Ethernet request came in from wire 1
decide which wire to send it out on, e.g. wire 2, 3, 4, 5, etc. You likely don't want to send it back through 1 where it came from.

After the destination is found, a confirmation is somehow sent back to the switch, which then learns which wire to send each MAC address to.

A switch is a bit like a router but it is a bit dumber/operates at a lower level: it basically operates only on MAC addresses, not on IP addresses.

The Internet service provider boxes most people have at home combines a switch for the local network and a router for the ISP communication.

Never trust an experiment that is not supported by a good theory Updated 2025-07-16

Not the usual bullshit you were expecting from the philosophy of Science, right?

Some notable quoters:

Jacques Monod has the exact quote as presented here: pubmed.ncbi.nlm.nih.gov/22042272/, though presumably it was in French, TODO find the French version
youtu.be/AYC5lE0b8os?t=41 A Computational Whole-Cell Model Predicts Genotype From Phenotype- Markus Covert by "Calit2ube" (2013), see also: Section "Whole cell simulation"
the book Genius: Richard Feynman and Modern Physics by James Gleick (1994) mentions a few incidents of this involving Feynman, see e.g. chapter "New Particles, New Language" where he and fellow theorist Hans Bethe immediately spot problems with experimentalists' data in suspicious results

Nick Leeson Updated 2025-07-16

Dude took down a bank.

Good documentary about it: Nick Leeson and the Fall of the House of Barings by Adam Curtis (1996).

One is reminded of Annie Dookhan.

One-form Updated 2025-07-16

www.youtube.com/watch?v=tq7sb3toTww&list=PLxBAVPVHJPcrNrcEBKbqC_ykiVqfxZgNl&index=19 mentions that it is a bit like a dot product but for a tangent vector to a manifold: it measures how much that vector derives along a given direction.

One page to rule them all Updated 2025-07-16

It is true that one image is worth a thousand words, but unfortunately it is also true that one image takes up at least as much bytes as a thousand words!

Having one single page to rule them all is of course the ideal setup for a website, as you can Ctrl + F one ToC and quickly find what you want.

And, with Linux Kernel Module Cheat Ciro noticed that it is very hard to write so much intelligent prose that becomes larger than reasonable to load on a single webpage.

He then started using this technique for everything he writes, including this page and Chinese government.

However, if there are too many images on the page, the loading of the last images would take forever in case users want to view the last sections.

There are two solutions to that:

be traditional and create separate web pages
be bold and load images as they appear on the viewport: stackoverflow.com/questions/2321907/how-do-you-make-images-load-only-when-they-are-in-the-viewport/57389607#57389607
Edit: OK, it was standardized with loading=lazy, without need JavaScript!
Now the last awesome thing would be a method that loads first images in viewport, then those below, and then those above, that would be the ultimate solution.
This question comes close: stackoverflow.com/questions/7906348/change-loading-order-of-images-already-on-page

Ciro is still deciding between those two. The traditional approach works for sure but loses the one page to rule them all benefits.

The innovative approach will work for interactive viewing, but archive.org will fail to load the images for example, and there may be other unforseen consequences.

Wikimedia Commons is awesome and automatically converts and serves smaller versions of images, so always choose the smallest images size needed by the output document. Readers can then find the higher resolution versions by following the page source.

This also comes to mind: motherfuckingwebsite.com

zettelkasten.de/posts/overview/ from zettelkasten:

How many Zettelkästen should I have? The answer is, most likely, only one for the duration of your life. But there are exceptions to this rule.

Onion service Updated 2025-07-16

This is a way to host a server that actually hide the IP of the server from the client, just like Tor hides the IP of the client from the server. Amazing tecnology!

This is why it enables hosting illegal things like the Silk Road: law enforcement is not able find where the server is hosted, and take it down or identify the owner.

Bibliography:

security.stackexchange.com/questions/38194/how-can-i-get-the-ip-address-for-a-tor-hidden-service-hs-with-a-onion-address

Online forums that lock threads after some time Updated 2025-07-16

Like Reddit (option to allow it per community added in late 2021) and support.google.com/.

And of course, 4chan just takes that to a whole new level, usually closing on the same day, and then getting deleted within a week. Why would anyone contribute non-illegal content to that king of system?!

Ridiculous, so when new information comes out, we just duplicate all the old comments on a new thread again?

Remember, Ciro Santilli is the Necromancer God.

Dan Dascalescu agrees for Reddit specifically: www.reddit.com/r/TheoryOfReddit/comments/9oujwf/why_archiving_old_threads_is_a_bigger_problem/

Open Images dataset Updated 2025-07-16

storage.googleapis.com/openimages/web/index.html

TODO vs COCO dataset.

As of v7:

~9M images
600 object classes
bounding boxes
visual relatoinships are really hard: storage.googleapis.com/openimages/web/factsfigures_v7.html#visual-relationships e.g. "person kicking ball": storage.googleapis.com/openimages/web/visualizer/index.html?type=relationships&set=train&c=kick
google.github.io/localized-narratives/ localized narratives is ludicrous, you can actually hear the (Indian women mostly) annotators describing the image while hovering their mouses to point what they are talking about). They are clearly bored out of their minds the poor people!

The images and annotations are both under CC BY, with Google as the copyright holder.

silkqin.com Updated 2025-07-16

www.silkqin.com/

John Thompson's Guqin website.

Holy crap amazing list of Guqin pieces by the guy for MP3 download! www.silkqin.com/06hear.htm And the explanations are insane. What a dude. Ciro Santilli's hero.

Download all MP3:

wget -r -np -l 1 -A mp3 http://www.silkqin.com/06hear.htm

Ciro Santilli Contacted John by email in 2019 telling him to put his stuff on YouTube and offering help, and he replied, but nothing came of it unfortunately. Edit: he uploaded a bunch of videos of him playing live in 2020! www.youtube.com/user/silkqin/videos

John focuses on playing the tunes in a "historically informed performance", in particular using silk strings rather than metal ones which are used by most modern artists: www.silkqin.com/08anal/hip.htm

Dialog between Fisherman and Woodcutter performed by John Thompson (2020)

Source.

Simple to state but hard to prove Updated 2025-07-16

One of the most beautiful things in mathematics are theorems of conjectures that are very simple to state and understand (e.g. for K-12, lower undergrad levels), but extremely hard to prove.

This is in contrast to conjectures in certain areas where you'd have to study for a few months just to precisely understand all the definitions and the interest of the problem statement.

Bibliography:

mathoverflow.net/questions/75698/examples-of-seemingly-elementary-problems-that-are-hard-to-solve
www.reddit.com/r/mathematics/comments/klev7b/whats_your_favorite_easy_to_state_and_understand/
mathoverflow.net/questions/42512/awfully-sophisticated-proof-for-simple-facts this one is for proofs for which simpler proofs exist
math.stackexchange.com/questions/415365/it-looks-straightforward-but-actually-it-isnt this one is for "there is some reason it looks easy", whatever that means

OpenStax Updated 2025-07-16

These people have good intentions.

The problem is that they don't manage to go critical because there's to way for students to create content, everything is manually curated.

You can't even publicly comment on the textbooks. Or at least Ciro Santilli hasn't found a way to do so. There is just a "submit suggestion" box.

This massive lost opportunity is even shown graphically at: cnx.org/about (archive) where there is a clear separation between:

"authors", who can create content
"students", who can consume content

Maybe this wasn't the case in their legacy website, legacy.cnx.org/content?legacy=true, but not sure, and they are retiring that now.

Thus, OurBigBook.com. License: CC BY! So we could re-use their stuff!

By Rice University.

TODO what are the books written in?

github.com/openstax/openstax-cms Uses Wagtail CMS. So presumaby they just Wagtail's WYSIWYG.
github.com/openstax/os-webview

Richard Baraniuk on open-source learning by TED (2006)

Source.