Xerox PARC Updated +Created
What a legendary place.
Kondo effect Updated +Created
If you adda bit of impurities to certain materials, at low temperatures of a few Kelvin their resistivity actually starts increasing if you go below a certain critical temperature.
Figure 1.
Kondo effect graph for gold with added impurities
. Source.
The Holy Trinity of popular Brazilian music Updated +Created
Eigenvalues and eigenvectors Updated +Created
Ł Updated +Created
Video 1.
Exploring! the Special Letters of the Polish Alphabet: L by Polish Girl Next Door (2021)
Source.
Zebrafish Updated +Created
Brexit Updated +Created
There are valid reasons to be pro-Brexit, given the uselessness of the European Union.
The problem was how the campaign was conducted, in a purely nationalistic, populist and fake news manner, and largely supported by business leaders who immediately after still wanted to hire cheap foreign labour, use tax havens and move headquarters to other countries, e.g.:
British politician Updated +Created
Eight Chinese Cuisines Updated +Created
This classification is too restrictive, and too South-centered. But if is worth knowing.
eLearning provider Updated +Created
Electromagnetic four-potential Updated +Created
A different and more elegant way to express Maxwell's equations by using the:instead of the:
Frederick Sanger Updated +Created
Ah, this seems like a nice dude.
Video 1.
Fred Sanger 1918-2013 by Birgitta Olofsson (2013)
Source. This is a good video especially is you know Cambridge, to help situate Sanger's places a bit. Good Sanger quote at the end:
I always tell people, it is much easier to get the second one than the first
The missing link between continuous and discrete AI Updated +Created
The old man lost his horse Updated +Created
Another notable reference is in Lost Horse LLC, MacKenzie Bezos's charity instrument.
Breakdown:
  • 塞翁 sai4 weng1: TODO his name?
  • 失马 shi1 ma3: lost horse
  • 焉知 yan1 zhi1: who knows, literary
  • 非福 fei1 fu2: bad (or) good
Video 1.
Zen master and the little boy scene from Charlie Wilson's War
. Source. This is how Ciro Santilli first heard the old man lost his horse! The scene happens after the Americans seem to have had sucess in arming the Taliban in the 1980s to fight the Soviets, and then they decide to stop all monetary help to rebuild the country, which then leads to a terrorism threat many years later.
Video 2.
The Blessing of Bad Luck by Pursuit of Wonder (2022)
Source. A bit too long. But worth it.
BIOS Updated +Created
Carleson's theorem Updated +Created
The Fourier series of an function (i.e. the function generated from the infinite sum of weighted sines) converges to the function pointwise almost everywhere.
The theorem also seems to hold (maybe trivially given the transform result) for the Fourier series (TODO if trivially, why trivially).
Only proved in 1966, and known to be a hard result without any known simple proof.
This theorem of course implies that Fourier basis is complete for , as it explicitly constructs a decomposition into the Fourier basis for every single function.
TODO vs Riesz-Fischer theorem. Is this just a stronger pointwise result, while Riesz-Fischer is about norms only?

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