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Ciro Santilli 37 Updated 2025-07-16

The traffic is designed for cars, which makes many red stops for bicycles completely stupid.

In a bicycle you just have too much more control and awareness than in a car, so if the way is completely clear, you should be allowed to stop, look if the way is clear, and then run reds.

Of course, this does increase the chances of hitting pedestrians a little bit. But the risk change feels so little that it would be worth it. Studies quoted by Wikipedia corroborate. It just feels extremely unintuitive to make cyclists stop in certain places when the street is clear.

www.theguardian.com/cities/2015/oct/27/cyclists-run-red-lights-paris-london-san-francisco Should cyclists be allowed to run red lights? by The Guardian 2015
www.vox.com/2014/5/9/5691098/why-cyclists-should-be-able-to-roll-through-stop-signs-and-ride

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Otto Ernst Heinrich Klemperer by

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Dilbert by

Ciro Santilli 37 Updated 2025-07-16

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The trash man is the best.

Official archive: dilbert.com/

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Musical instrument by

Ciro Santilli 37 Updated 2025-07-16

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Physics Stack Exchange by

Ciro Santilli 37 Updated 2025-07-16

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physics.stackexchange.com/

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Accounts controlled by Ciro Santilli by

Ciro Santilli 37 Updated 2025-07-16

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Ciro Santilli controls the following accounts.

With non-trivial activity:

github.com/cirosantilli on GitHub
stackoverflow.com/users/895245 on Stack Overflow
www.linkedin.com/in/cirosantilli on LinkedIn
www.youtube.com/c/CiroSantilli on YouTube
Twitter: see Section "Ciro Santilli's Twitter accounts"
archive.org/details/@cirosantilli2 on the Internet Archive. Was archive.org/details/@cirosantilli but got deleted due to an "admin error" and the old username cannot be restored!^[ref]
en.wikipedia.org/wiki/User:Cirosantilli2 and commons.wikimedia.org/wiki/User:Cirosantilli2: Ciro tries to upload all educational CC content he creates to Wikimedia Commons as an extra backup and sometimes to use in Wikipedia pages
www.facebook.com/cirosantilli/ Ciro accepts all friend requests there, but expect a few non-technical posts. Unless you look like a massive honeypot account, please send context in advance in that case.
www.quora.com/profile/Ciro-Santilli
www.reddit.com/user/cirosantilli/ is Ciro's Reddit account, mostly computer and China topics
maps.app.goo.gl/npV35XTppSBTmNqC8: Google Maps. Ciro Santilli likes to make additions to certain niche topics that are missing, having reached Local Guide Level 6 as of 2024. He can't do as much as he'd like so as to not reveal his current city however.

Trivial or no activity:

Profiles without URLs (OMG...):

Discord: username cirosantilli, previously cirosantilli#8921

Accounts in Chinese websites. These accounts might be banned or altered or offer other limitations, so Ciro only communicates briefly through them. All communication through those channels should obviously be assumed to be compromised:

bbs.nibaedu.com/index.php?m=space&uid=70
www.renren.com/338003848/profile
www.tianya.cn/109285544 (can't post, no cell phone)
hacpai.com/member/cirosantilli unable to login as of 2019-10-12, reason unclear, either ban or website too crappy.
pincong.rocks/people/cirosantilli Lost account tested as of 2022-11 and likely much earlier. Last existing password not working, and there doesn't seem to be a reset password button. Creating cirosantilli2
pincong.rocks/people/cirosantilli2
tieba.baidu.com/home/main?id=5cd56369726f73616e74696c6c69c944
v2ex.com/member/cirosantilli: Ciro was blocked and or account deleted on 2020-07-23: cirosantilli.com/china-dictatorship/v2ex
- v2ex.com/member/cirosantilli2: was created by someone else most likely and cannot be re-registered. Also blocked.
- v2ex.com/member/cirosantilli3: Ciro created this new account November 2023, let's see how long it lasts.
www.zhihu.com/people/cirosantilli. Ciro was prevented from posting in 2018-06-25, and the account and all content mentioning him were taken down in 2019-11-03.
www.weibo.com/p/1005055601627311: started requiring a cell phone to login in 2020, and Ciro didn't want to give his cell phone number to the CCP and didn't have the patience to manage a secondary phone number, so he is not logging in for now. The account was blocked in 2021: cirosantilli.com/china-dictatorship/ciro-santillis-weibo-block

Accounts in Russian websites:

vk.com/id595305194

Dead websites:

www.citeulike.org/user/cirosantilli (2019-05)

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Liquid slugging by

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Americas by

Ciro Santilli 37 Updated 2025-07-16

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Welteislehre by

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Schrödinger equation by

Ciro Santilli 37 Updated 2025-07-16

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The partial differential equation of non-relativistic quantum mechanics.

Experiments explained:

via the Schrödinger equation solution for the hydrogen atom it predicts:
- spectral line basic lines, plus Zeeman effect
Schrödinger equation solution for the helium atom: perturbative solutions give good approximations to the energy levels
double-slit experiment: I think we have a closed solution for the max and min probabilities on the measurement wall, and they match experiments

Experiments not explained: those that the Dirac equation explains like:

To get some intuition on the equation on the consequences of the equation, have a look at:

The easiest to understand case of the equation which you must have in mind initially that of the Schrödinger equation for a free one dimensional particle.

Then, with that in mind, the general form of the Schrödinger equation is:

i ℏ \frac{\partial ψ ( x , t )}{\partial t} = \hat{H} [ψ (x, t)]

(1)

Equation 1.

Schrodinger equation

where:

$ℏ$ is the reduced Planck constant
$ψ$ is the wave function
$t$ is the time
$\hat{H}$ is a linear operator called the Hamiltonian. It takes as input a function $ψ$ , and returns another function. This plays a role analogous to the Hamiltonian in classical mechanics: determining it determines what the physical system looks like, and how the system evolves in time, because we can just plug it into the equation and solve it. It basically encodes the total energy and forces of the system.

The

x

argument of

ψ

could be anything, e.g.:

we could have preferred polar coordinates instead of linear ones if the potential were symmetric around a point
we could have more than one particle, e.g. solutions of the Schrodinger equation for two electrons, which would have e.g. $x_{1}$ and $x_{2}$ for different particles. No matter how many particles there are, we have just a single $ψ$ , we just add more arguments to it.
we could have even more generalized coordinates. This is much in the spirit of Hamiltonian mechanics or generalized coordinates

Note however that there is always a single magical

t

time variable. This is needed in particular because there is a time partial derivative in the equation, so there must be a corresponding time variable in the function. This makes the equation explicitly non-relativistic.

The general Schrödinger equation can be broken up into a trivial time-dependent and a time-independent Schrödinger equation by separation of variables. So in practice, all we need to solve is the slightly simpler time-independent Schrödinger equation, and the full equation comes out as a result.

Existence and uniqueness: mathoverflow.net/questions/212913/existence-and-uniqueness-for-two-dimensional-time-dependent-schr%C3%B6dinger-equation

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Quantum yield by

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Quantum yield is a measure of the efficiency of a photophysical or photochemical process, defined as the ratio of the number of events of a specific type (such as emitted photons, formed molecules, etc.) to the number of photons absorbed. It is a dimensionless quantity often expressed as a decimal or a percentage.

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Kutta–Joukowski theorem by

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Diorama by

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Mono and paraphyly by

Ciro Santilli 37 Updated 2025-07-16

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3D rigid body dynamics simulator by

Ciro Santilli 37 Updated 2025-07-16

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Lord of the Rings by

Ciro Santilli 37 Updated 2025-07-16

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Real-time attack speedrun by

Ciro Santilli 37 Updated 2025-07-16

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A non-tool-assisted speedrun.

Ciro Santilli views humans as biological robots, and therefore RTA videos can be thought of as probabilistic TAS with human achievable reflex constraints.

This aspect is especially highlighted in "speed run record evolution videos", which can be quite fun, e.g. www.youtube.com/watch?v=pmS9e7kzgS4 Ocarina of Time - World Record History and Progression (Any% Speedrun, 1990s-2017) by retro (2017)

From a similar point of view, Ciro also sometimes watches/learns a bit about competitive PvP games from a "could a computer play this better than a human" point of view.

Ciro also likes to watch commented manual speedruns of games as a way of experiencing the game at a high level without spending too much time on it, often from Games Done Quick. Their format is good because it generally showcases one player focusing more on the gameplay, and three couch commentators to give context, that's a good setup.

It is a

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Works about Richard Feynman by

Ciro Santilli 37 Updated 2025-07-16

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Richard Feynman's drug use by

Ciro Santilli 37 Updated 2025-07-16

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From Surely You're Joking, Mr. Feynman chapter O Americano, Outra Vez!:

The people from the airlines were somewhat bored with their lives, strangely enough, and at night they would often go to bars to drink. I liked them all, and in order to be sociable, I would go with them to the bar to have a few drinks, several nights a week.
One day, about 3:30 in the afternoon, I was walking along the sidewalk opposite the beach at Copacabana past a bar. I suddenly got this treMENdous, strong feeling: "That's just what I want; that'll fit just right. I'd just love to have a drink right now!"
I started to walk into the bar, and I suddenly thought to myself, "Wait a minute! It's the middle of the afternoon. There's nobody here, There's no social reason to drink. Why do you have such a terribly strong feeling that you have to have a drink?" - and I got scared.
I never drank ever again, since then. I suppose I really wasn't in any danger, because I found it very easy to stop. But that strong feeling that I didn't understand frightened me. You see, I get such fun out of thinking that I don't want to destroy this most pleasant machine that makes life such a big kick. It's the same reason that, later on, I was reluctant to try experiments with LSD in spite of my curiosity about hallucinations.

One notable drug early teens Ciro consumed was Magic: The Gathering, see also: Section "Magic: The Gathering is addictive".

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Niobium-Titanium by

Ciro Santilli 37 Updated 2025-07-16

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 Pinned article: Introduction to the OurBigBook Project

Welcome to the OurBigBook Project! Our goal is to create the perfect publishing platform for STEM subjects, and get university-level students to write the best free STEM tutorials ever.

Everyone is welcome to create an account and play with the site: ourbigbook.com/go/register. We belive that students themselves can write amazing tutorials, but teachers are welcome too. You can write about anything you want, it doesn't have to be STEM or even educational. Silly test content is very welcome and you won't be penalized in any way. Just keep it legal!

Video 1.

Intro to OurBigBook

. Source.

We have two killer features:

topics: topics group articles by different users with the same title, e.g. here is the topic for the "Fundamental Theorem of Calculus" ourbigbook.com/go/topic/fundamental-theorem-of-calculus
Articles of different users are sorted by upvote within each article page. This feature is a bit like:
- a Wikipedia where each user can have their own version of each article
- a Q&A website like Stack Overflow, where multiple people can give their views on a given topic, and the best ones are sorted by upvote. Except you don't need to wait for someone to ask first, and any topic goes, no matter how narrow or broad
This feature makes it possible for readers to find better explanations of any topic created by other writers. And it allows writers to create an explanation in a place that readers might actually find it.
Figure 1.
Screenshot of the "Derivative" topic page
. View it live at: ourbigbook.com/go/topic/derivative
Video 2.
OurBigBook Web topics demo
. Source.
local editing: you can store all your personal knowledge base content locally in a plaintext markup format that can be edited locally and published either:
- to OurBigBook.com to get awesome multi-user features like topics and likes
- as HTML files to a static website, which you can host yourself for free on many external providers like GitHub Pages, and remain in full control
This way you can be sure that even if OurBigBook.com were to go down one day (which we have no plans to do as it is quite cheap to host!), your content will still be perfectly readable as a static site.
Figure 2.
You can publish local OurBigBook lightweight markup files to either OurBigBook.com or as a static website
.
Figure 3.
Visual Studio Code extension installation
.
Figure 4.
Visual Studio Code extension tree navigation
.
Figure 5.
Web editor
. You can also edit articles on the Web editor without installing anything locally.
Video 3.
Edit locally and publish demo
. Source. This shows editing OurBigBook Markup and publishing it using the Visual Studio Code extension.
Video 4.
OurBigBook Visual Studio Code extension editing and navigation demo
. Source.
Internal cross file references done right:
Infinitely deep tables of contents:
Figure 6.
Dynamic article tree with infinitely deep table of contents
.
Live URL: ourbigbook.com/cirosantilli/chordate
Descendant pages can also show up as toplevel e.g.: ourbigbook.com/cirosantilli/chordate-subclade

All our software is open source and hosted at: github.com/ourbigbook/ourbigbook

Further documentation can be found at: docs.ourbigbook.com

Feel free to reach our to us for any help or suggestions: docs.ourbigbook.com/#contact

 Site settings

 Pinned article: Introduction to the OurBigBook Project  Hide

 Pinned article: Introduction to the OurBigBook Project