Conservation of energy by Ciro Santilli 35 Updated +Created
Alex Honnold by Ciro Santilli 35 Updated +Created
Current-voltage characteristic by Ciro Santilli 35 Updated +Created
Light-emitting diode by Ciro Santilli 35 Updated +Created
Video 1.
How LEDs work by VirtualBrain
. Source. 2021. Good 3d schematics clearly explaining part of the LED electronic package.
Voltage transformer by Ciro Santilli 35 Updated +Created
TEM vs SEM by Ciro Santilli 35 Updated +Created
TEM: sample has to be very thin, you get a 2D image. Higher resolution possible.
SEM: sample does not need to be ultra thin, you get a 3D image. Lower resolution possible.
Electric battery by Ciro Santilli 35 Updated +Created
Free education by Ciro Santilli 35 Updated +Created
Exam by Ciro Santilli 35 Updated +Created
Exams as a prerequisite for a degree are useless. Exams as part of a degree must be abolished. And degrees must be abolished. Ultimately the only metrics that really matter are money and fame. See also: motivation.
The only thing exams should matter for is as a screening tool to select people with specific abilities that you care about as an employer or principal investigator. If:
  • you have no idea about what the content of specific exams are (and you don't because they are all ad-hoc university secrets)
  • or don't have a way to machine learn what grades correlate with your desired performance (you don't because where's the data?)
then exams are useless for your purposes. then might as well just go by interviews (basically what all employers do already, though not PIs). Degrees are too course grained to mean anything to anybody. Employers and PIs likely only care about very few specific subjects.
Once the question of an exam has been formulated, the usefulness of the problem is already been completely destroyed, because formulating the problem that matters is the most important part of things. And any problem with an answer, is useless to put effort into: give answers.
Furthermore, preventing people from searching for answers while answering an exam, AKA preventing "cheating", also makes absolutely no sense. In the real world, we want people to find answers as quickly as possible! We should be teaching people how to "cheat"! What we should teach them instead is what a fucking license is, and what you have to do to comply with it.
And if you pass the exam, you pass the course, without any further time requirements.
And those exams must be applied by professional test application companies to ensure no cheating and to factor out the anti-cheat work, while still making the tests available to people anywhere.
A quote from Richard Feynman present in the book Surely You're Joking, Mr. Feynman chapter O Americano, Outra Vez!:
You cannot get educated by this self-propagating system in which people study to pass exams, and teach others to pass exams, but nobody knows anything.
You learn something by doing it yourself, by asking questions, by thinking, and by experimenting.
The only metric that matters is "to feel that you've satisfied youre curiosity". When one studies for that, it can take a lot more time to actually learn everything, because it is sometimes not as clear when you should stop. But it is the only way to go deeper.
A person's understanding is the most illiquid asset that exists, to judge that based only on standardized exams, is a certain way to fail to identify top talent.
Angle by Ciro Santilli 35 Updated +Created
Cancer by Ciro Santilli 35 Updated +Created
Product of group subsets by Ciro Santilli 35 Updated +Created
Infinitely differentiable function by Ciro Santilli 35 Updated +Created
Street reclamation by Ciro Santilli 35 Updated +Created
Only people who need to drive a car should be allowed to drive a car anywhere near a city, e.g. people who work door to door, people who are disabled, etc.
Countryside driving is fine. If going to a city, you just have to drive to a parking outside of the city where you then take the public transport. And those who live in cities must leave their cars there too.
Everyone else must walk or cycle from home to public transport.
Cars just destroy everything, they make everything ugly:
  • this was extremely clear to Ciro Santilli as a cyclist. He previously lived in a place with few cars and the countryside was so pleasant. Then he moved to a place with more cars and it was shocking. It's a mixture of pollution, noise, and the fact that roads cut up the countryside that just make things not pleasant at all. Dual lane roads in particular are just a terrible thing. You can hear them from afar, much before you see them.
    You can just see as tiny little villages surrounding the bit city and it's oversized motorways are more or less homogenized into one big city mass, the process is clearly visible as you cycle out of the big city and the villages become nicer and more unique as you go along further out.
  • even within cities, cars completely dehumanize the streets. For example, Ciro once lived in a small dead end street, and he would have gladly opened his front window more often to meet the neighbours. But just the noise of cars passing by every so often makes it impractical to work like that.
The Zatoichi effect applies well to the problem of cyclists:
  • they are not really pedestrians, and pedestrian paths are not suitable to them because they are too narrow, of not smooth, or curved. But pedestrians will always have enough political power to have their paths, because they live around the paths
  • they are not really motor vehicles, because motor vehicle paths are too wide and too fast for them. But motor vehicles will always have enough political power to have their paths, because people are lazy and stupid, and because as the world stands, individually you just don't have any reasonable choice to go anywhere.
This is the main drama faced by cyclists.
Lobbying groups:
Video 1.
Why isn't cycling normal in London? by Jay Foreman (2018)
Source.
Control engineering by Ciro Santilli 35 Updated +Created
Controlled language by Ciro Santilli 35 Updated +Created
Connected component by Ciro Santilli 35 Updated +Created
When a disconnected space is made up of several smaller connected spaces, then each smaller component is called a "connected component" of the larger space.
See for example the
Condensed matter Physics bibliography by Ciro Santilli 35 Updated +Created

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