Logarithmic integral function Updated 2025-07-16
Sample software implementations:
Lorentz transformation Updated 2025-07-16
The equation that allows us to calculate stuff in special relativity!
Take two observers with identical rules and stopwatch, and aligned axes, but one is on a car moving at towards the direction at speed .
When both observe an event, if we denote:It is of course arbitrary who is standing and who is moving, we will just use the term "standing" for the one without primes.
- the observation of the standing observer
- the observation of the ending observer on a car
Note that if tends towards zero, then this reduces to the usual Galilean transformations which our intuition expects:
Lorentz transform consequence: everyone sees the same speed of light Updated 2025-07-16
OK, so let's verify the main desired consequence of the Lorentz transformation: that everyone observes the same speed of light.
Observers will measure the speed of light by calculating how long it takes the light going towards cross a rod of length laid in the x axis at position .
Each observer will observe two events:
Supposing that the standing observer measures the speed of light as and that light hits the left side of the rod at time , then he observes the coordinates:
Now, if we transform for the moving observer:and so the moving observer measures the speed of light as:
Los Alamos National Laboratory Updated 2025-07-16
Historian Alan B. Carr:
- www.youtube.com/@AlanBCarr. IMPORTANT NOTE: Although Alan B. Carr is a Los Alamos National Laboratory (LANL) employee, this page has absolutely no formal connection with LANL.
lujakob/nestjs-realworld-example-app SQLite port Updated 2025-07-16
Tried a quick port to SQLite to get rid of annoying local databases for development, but failed, at c1c2cc4e448b279ff083272df1ac50d20c3304faandthen:fails with:Attempt to hack it:and after that it seems to run.
npm install sqlite3 --save-dev{
"type": "sqlite",
"database": "db.sqlite3",
"entities": ["src/**/**.entity{.ts,.js}"],
"synchronize": true
}npm startDataTypeNotSupportedError: Data type "timestamp" in "ArticleEntity.created" is not supported by "sqlite" database.--- a/src/article/article.entity.ts
+++ b/src/article/article.entity.ts
@@ -20,10 +20,10 @@ export class ArticleEntity {
@Column({default: ''})
body: string;
- @Column({ type: 'timestamp', default: () => "CURRENT_TIMESTAMP"})
+ @Column({ default: () => "CURRENT_TIMESTAMP"})
created: Date;
- @Column({ type: 'timestamp', default: () => "CURRENT_TIMESTAMP"})
+ @Column({ default: () => "CURRENT_TIMESTAMP"})
updated: Date;I can signup and login, terrible error reporting as usual, make sure to use long enough usernames/passwords.
However, article creation fails with:
Unhandled Rejection (TypeError): Cannot read property 'slug' of undefined Luminiferous aether Updated 2025-07-16
Can you just imagine what if luminiferous aether was one single fixed rigid body? This is apparently what Maxwell believed, Subtle is the Lord by Abraham Pais (1982) page 111 quoting his entry to Encyclopedia Britannica:Then it would provide a natural space coordinate for the entire universe!
There can be no doubt that the interplanetary and interstellar spaces are not empty but are occupied by a material substance or body, which is certainly the largest, and probably the most uniform, body of which we have any knowledge.
Machine learning Updated 2025-07-16
The main reason Ciro Santilli never touched it is that it feels that every public data set has already been fully mined or has already had the most interesting algorithms developed for it, so you can't do much outside of big companies.
This is why Ciro started Ciro's 2D reinforcement learning games to generate synthetic data and thus reduce the cost of data.
The other reason is that it is ugly.
Machine learning as a form of data compression Updated 2025-07-16
Machine learning company Updated 2025-07-16
This section is about companies that primarily specialize in machine learning.
The term "machine learning company" is perhaps not great as it could be argued that any of the Big tech are leaders and sometimes, especially in the case of Google, has a main product that is arguably a form of machine learning.
MacOS Updated 2025-07-16
Nice looking and expensive operating system by Apple. Ciro Santilli believes that:
- if you want to be ripped off, just use Microsoft Windows which has more software available
- or if you want to attain Enlightenment, just use Linux, which is free and open source
Madelung energy ordering rule Updated 2025-07-16
Looking at the energy level of the Schrödinger equation solution for the hydrogen atom, you would guess that for multi-electron atoms that only the principal quantum number would matter, azimuthal quantum number getting filled randomly.
However, orbitals energies for large atoms don't increase in energy like those of hydrogen due to electron-electron interactions.
In particular, the following would not be naively expected:
This rule is only an approximation, there exist exceptions to the Madelung energy ordering rule.
Magic Aids Updated 2025-07-16
His combination of politically incorrect dirt talk with amazing quirky decks captures Ciro's imagination.
Anonymous no face-reveal.
The videos are heavily edited with all pauses cut out, which makes them very quick to watch and saves viewer time.
Modern focused, with some occasional newer formats mixed in.
When Wizards publishes several useless sets in a row without a single modern playable card, he's just forced into Standard.
Ciro Santilli's body Updated 2025-07-16
31 year old:
- Height:
- Weight:
- Chest: 94cm
- Waist: 81.5cm
- Hip: 85.5cm
- Inner leg: 92.0cm
- Length of back: 71cm (from base of neck to knuckle height)
- Collar: 38cm
- Sitbone distance (ischial tuberosity):
- sitting on cardboard: 110mm, this method felt accurate
- www.youtube.com/watch?v=xSWlwzqGKik water method: 90mm/100mm. Small butt!?
- Arm sleeve length: 61.5 cm
- Head circumference: 58.5 cm
- Hand:
- circumference: 19.8 cm around open hand knuckle
- Tip Of Middle Finger To Crease Under Palm: 20 cm
- Circunference around closed knuckle: 25 cm
- Hand great span en.wikipedia.org/wiki/Span_(unit): 0.22m
- Erect penis length: just kidding, just kidding. Ciro Santilli's wife would kill him.
- rest heart rate: 60 BPM
Magic: The Gathering meta-based deck choice is a bimatrix game Updated 2025-07-16
Ciro had initially Googled for the "4-card limit thought experiment" but he reached: www.channelfireball.com/articles/what-if-the-4-card-limit-was-abolished-in-modern/ "What if the 4-Card Limit Was Abolished in Modern?" by Frank Karsten (2018) and was much more pleased with the mathematical result. Like-minded people.
That links to www.channelfireball.com/articles/what-if-the-4-card-limit-was-abolished-in-modern/ the related article: "The Mythic Invitational's Duo Standard Format Game Theory Optimized" by Frank Karsten (2019) which explains well how Nash equilibrium is naturally reached: if there is any imbalance, someone can take advantage of it, and then it rebalances. Therefore once you've calculated the equilibrium, your best course of action is to pick a deck at random from a list of possible winners.
Hertz electromagnetic wave experiments Updated 2025-07-16
Heinrich Hertz's main initial experiment used a spark-gap transmitter. It is not something that transmits recorded sounds like voice: it only transmits noisy beeps. And as such was used for wireless telegraphy.
- a piezo igniter from a barbequeue lighter
- a more powerful home-made transformer
Hertz and Radio waves Explained by PhysicsHigh (2016)
Source. Simple schematics showing the basics of the experiments. No choice of components rationale. Magic the gathering's banning of 7 cards due to "racism" (2020) Updated 2025-07-16
Official announcement: magic.wizards.com/en/articles/archive/news/depictions-racism-magic-2020-06-10
List of cards with images: www.hipstersofthecoast.com/2020/06/wizards-bans-7-cards-that-depict-racism-including-invoke-prejudice/
- Invoke prejudice: depicts the Ku Klux Klan. Card's title clearly criticizes them "prejudice".
- Stone-Throwing Devils: not sure about this one: boardgames.stackexchange.com/questions/54341/what-is-offensive-about-the-card-stone-throwing-devils
- Cleanse: it does not seem to have any reference to black people, image depicts fantastic animals. There are hundreds of cards that talk about black since it is one of the 5 colors of magic.
- Pradesh Gypsies: does not appear to suggest any bad things about gypsies, on the contrary
- Jihad: does not appear to suggest any bad things about Islam, on the contrary
- Imprison: depicts a black slave. Let's pretend it never happened.
- Crusade: pretend it never happened
Magnetic dipole Updated 2025-07-16
A tiny idealized magnet! It is a very good model if you have a small strong magnet interacting with objects that are far away, notably other magnetic dipoles or a constant magnetic field.
The cool thing about this model is that we have simple explicit formulas for the magnetic field it produces, and for how this little magnet is affected by a magnetic field or by another magnetic dipole.
Quotient group Updated 2025-07-16
Ultimate explanation: math.stackexchange.com/questions/776039/intuition-behind-normal-subgroups/3732426#3732426
Does not have to be isomorphic to a subgroup:
This is one of the reasons why the analogy between simple groups of finite groups and prime numbers is limited.
Magnetic resonance imaging Updated 2025-07-16
How MRI Works Part 1 by thePIRL (2018)
Source. - youtu.be/TQegSF4ZiIQ?t=326 the magnet is normally always on for the entire lifetime of the equipment!
- youtu.be/TQegSF4ZiIQ?t=465 usage of non-ionizing radiation (only radio frequencies) means that it is very safe to use. The only dangerous part is the magnetic field interacting with metallic objects.
Dr Mansfield's MRI MEDICAL MARVEL by BBC
. Source. Broadcast in 1978. Description:Tomorrow's World gave audiences a true world first as Dr Peter Mansfield of the University of Nottingham demonstrated the first full body prototype device for Magnetic resonance imaging (MRI), allowing us to see inside the human body without the use of X-rays.
Maiden Voyage by Herbie Hancock (1965) Updated 2025-07-16
There are unlisted articles, also show them or only show them.