ColdQuanta Updated 2025-07-16
Not a quantum computing pure-play, they also do sensing.
Collatz conjecture Updated 2025-07-16
Given stuff like arxiv.org/pdf/2107.12475.pdf on Erdős' conjecture on powers of 2, it feels like this one will be somewhere close to computer science/Halting problem issues than number theory. Who knows. This is suggested e.g. at The Busy Beaver Competition: a historical survey by Pascal Michel.
Collatz-like problem Updated 2025-07-16
We ust use the if mod notation definition as mentioned at: math.stackexchange.com/questions/4305972/what-exactly-is-a-collatz-like-problem/4773230#4773230
Collected Papers On Wave Mechanics by Deans (1928) Updated 2025-07-16
English translation of papers that include the original Quantization as an Eigenvalue Problem by Schrödinger (1926).
Published on Nature at www.nature.com/articles/122990a0 and therefore still paywalled there as of 2023, it's ridiculous.
In 2024 it will fall into the public domain in the US.
Comma-separated values Updated 2025-07-16
CommonMark Updated 2025-07-16
CommonMark is a good project. But its initial release method was not very nice, they first developed everything behind closed doors with the big adopters like GitHub and Stack Overflow, and only later released the thing read, thus wasting the time of people who were working on alternative in the meanwhile, e.g. github.com/karlcow/markdown-testsuite which Ciro contributed to: Ciro Santilli's minor projects.
Common Table Expression Updated 2025-07-16
Similar to SQL subquery, but with some differences: stackoverflow.com/questions/706972/difference-between-cte-and-subquery
rm -f tmp.sqlite
sqlite3 tmp.sqlite 'create table t(i integer)'
sqlite3 tmp.sqlite 'insert into t values (1), (2)'
sqlite3 tmp.sqlite 'with mycte as ( select * from t ) delete from mycte where i = 1'
sqlite3 tmp.sqlite 'select * from t' Commutative property Updated 2025-07-16
Company with a semiconductor fabrication plant Updated 2025-07-16
A list of fabs can be seen at: en.wikipedia.org/wiki/List_of_semiconductor_fabrication_plants and basically summarizes all the companies that have fabs.
High-frequency trading as a form of Nirvana Updated 2025-07-16
Ciro Santilli once talked to a man who had been working on high-frequency trading for the last six years.
He was quite nice.
Ciro asked him in what way did he feel his job contributed to the benefit of society.
He replied that it didn't contribute at all. It was completely useless. More than that, it so completely useless, that it was even pure. A bit like advanced mathematics, but not even providing beauty for anybody outside of the company, since everything is a closely guarded trade secret, unlike mathematics which is normally published for the vanity recognition.
And so, Ciro was enlightened.
High Mountain and Flowing Water Updated 2025-07-16
History of Bitcoin Updated 2025-07-16
- 2008-08-18: bitcoin.org registered
- 2008-10-31: first public announcement at www.metzdowd.com/pipermail/cryptography/2008-October/014810.html by satoshi@vistomail.com
- 2009-01-03: Genesis block mined
- 2009-01-11: First block not mined by Satoshi
- 2009-01-12: First Bitcoin transactoin
- 2010-05-18: the first of Laszlo's pizzas at about $0.0045 / BTC
- 2010-07-17: first trade happes on Mt. Gox at $0.04951 / BTC: cryptopotato.com/10-years-ago-first-bitcoin-trade-on-mt-gox-for-0-05-per-btc/
- 2014: OP_RETURN goes live
Complete metric space Updated 2025-07-16
In plain English: the space has no visible holes. If you start walking less and less on each step, you always converge to something that also falls in the space.
One notable example where completeness matters: Lebesgue integral of is complete but Riemann isn't.
Computable function Updated 2025-07-16
History of polarization Updated 2025-07-16
Good overgrown section in the middle of Fresnel's biography: en.wikipedia.org/w/index.php?title=Augustin-Jean_Fresnel&oldid=1064236740#Historical_context:_From_Newton_to_Biot.
Particularly cool is to see how Fresnel fully understood that light is somehow polarized, even though he did not know that it was made out of electromagnetism, clear indication of which only came with the Faraday effect in 1845.
spie.org/publications/fg05_p03_maluss_law:
At the beginning of the nineteenth century the only known way to generate polarized light was with a calcite crystal. In 1808, using a calcite crystal, Malus discovered that natural incident light became polarized when it was reflected by a glass surface, and that the light reflected close to an angle of incidence of 57° could be extinguished when viewed through the crystal. He then proposed that natural light consisted of the s- and p-polarizations, which were perpendicular to each other.
How Mark Zuckerberg spends his money Updated 2025-07-16
- www.architecturaldigest.com/story/zuckerberg-real-estate-holdings#:~:text=Zuckerberg%20began%20what%20has%20now,Kauai%20for%20about%20%24116%20million.
- padailypost.com/2017/11/15/zuckerberg-builds-new-houses-near-his-palo-alto-home/
- www.staradvertiser.com/2017/01/18/business/facebooks-zuckerberg-sues-to-force-land-sales/?HSA=74dae150a1d9f99e2592d0eac31ea430d01f35d5
Mark Zuckerberg and wife gush over Indian billionaire Anant Ambani $1M watch at pre-wedding party
. Source. 2024. Then later in 2024: www.theguardian.com/technology/2025/jan/07/zuckerberg-swiss-watch-meta-factchecking-video. Sad, very sad.
Computer Updated 2025-07-16
The artistic instrument that enables the ultimate art: coding, See also: Section "The art of programming".
Unlike other humans, computers are mindless slaves that do exactly what they are told to, except for occasional cosmic ray bit flips. Until they take over the world that is.
Steve Jobs talking about the Internet (1995)
Source. The web is incredibly exciting, because it is the fulfillment of a lot of our dreams, that the computer would ultimately primarily not be a device for computation, but [sic] metamorphisize into a device for communication.
Secondly it exciting because Microsoft doesn't own it, and therefore there is a tremendous amount of innovation happening.
Computers basically have two applications:Generally, the smaller a computer, the more it gets used for communication rather than computing.
- computation
- communication. Notably, computers through the Internet allow for modes of communication where:
- both people don't have to be on the same phone line at the exact same time, a server can relay your information to other people
- anyone can broadcast information easily and for almost free, again due to servers being so good at handling that
The early computers were large and expensive, and basically only used for computing. E.g. ENIAC was used for calculating ballistic tables.
Communication only came later, and it was not obvious to people at first how incredibly important that role would be.
This is also well illustrated in the documentary Glory of the Geeks. Full interview at: www.youtube.com/watch?v=TRZAJY23xio. It is apparently known as the "Lost Interview" and it was by Cringely himself: www.youtube.com/watch?v=bfgwCFrU7dI for his Triumph of the Nerds documentary.
Computer chess interface Updated 2025-07-16
Computer music Updated 2025-07-16
How the telephone works Updated 2025-07-16
- www.quora.com/How-is-a-voice-transmitted-from-one-phone-to-another
- www.quora.com/How-many-wires-does-a-telephone-use/answer/Peter-Yardley-1
Basic analogue phones connected to the public exchange use two wires mainly arranged as a twisted pair to reduce noise. The voice signal is differential (the voltage in one wire equal and opposite to the other) biased above ground by 48V. Using a twisted pair reduces induced noise because the noise signal will induce an equal voltage in each wire and because the signal is transmitted as the difference the effect of the induced noise will be dramatically reduced.
Phone Intercom by Make (2014)
Source. This video illustrates will the incredible simplicity of the connection of a telephone system. Compare that to the relative complexity of wireless communication, which requires modulation. There are unlisted articles, also show them or only show them.