Real projective plane Updated 2025-07-16
For some reason, Ciro Santilli is mildly obsessed with understanding and visualizing the real projective plane.
To see why this is called a plane, move he center of the sphere to , and project each line passing on the center of the sphere on the x-y plane. This works for all points of the sphere, except those at the equator . Those are the points at infinity. Note that there is one such point at infinity for each direction in the x-y plane.
Dedekind cut Updated 2025-07-16
Real line Updated 2025-07-16
Real plane Updated 2025-07-16
Dimension Updated 2025-07-16
Euclidean space Updated 2025-07-16
with extra structure added to make it into a metric space.
Fraction Updated 2025-07-16
Quora Updated 2025-07-16
Quora is crap in many, many senses, but in part due to some bad Stack Overflow policies, it is the best crap we've got for certain (mostly useless) subjects. Until OurBigBook.com dominates the world.
The worst thing about quora is that you cannot subscribe only to certain subjects on your feed. Quora just keeps pumping shit you never subscribed to, no matter what. Ciro, for sport, unfollowed every single idiotic subject it was proposing, but it didn't work, sooner or later Quora just keeps pumping more shit back. Mind you, some of that shit is fun. But it's still shit. Though on second thought, YouTube also randomly decides to reset Ciro's humongous "don't recomend this shitty channel" choices from time to time, which is not much different...
Other terrible things, they just seem to have an incredible ability of making the website worse and more annoying over time! Truly amazing:
Quora is getting so bad that it is basically being killed by Reddit, especially after they lifted the 6-month hard thread lock...
See also: cirosantilli.com/china-dictatorship/quora for a coverage of the intense pro-CCP astroturfing present on the website.
Stack Overflow Updated 2025-07-16
The best place to get answers to programming questions as of 2019. Google into Stack Overflow is always the best bet.
An overview of Ciro Santilli's Stack Overflow contribution can be found at: Ciro Santilli's Stack Overflow contributions.
Figure 1.
Stack Overflow in a nutshell
. Source.
As the "WTF look at my points" guy, Ciro Santilli approves of this meme. A few more elements could be added, notably deletion of the last link-only answer, but good enough.
By the profile image, the "Grammar Nazi" editor is actually appropriately the notorious serial editor Peter Mortensen. Ciro Santilli welcomes grammar fixes, but more subjective style fixes can be a bit annoying.
Modus ponens Updated 2025-07-16
Breakthrough Prize Updated 2025-07-16
By Zuckerberg. The selection seems decent. And natural sciences only, which is good. A bit more application oriented than the Nobel Prize it seems, e.g. 2022 separates physics and fundamental physics.
Appears to explain award reasoning even worse than the Nobel Foundation.

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