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If there is one thing that makes Ciro Santilli learn German, this is it (the Romance language are all the same, so reading them is basically covered for Ciro already).
Ciro Santilli intends to move his beauty list here little by little: github.com/cirosantilli/mathematics/blob/master/beauty.md
The most beautiful things in mathematics are results that are:
- simple to state but hard to prove:
- Fermat's Last Theorem
- number of unknown rationality, e.g. is rational?
- transcendental number conjectures, e.g. is transcendental?
- basically any conjecture involving prime numbers:
- many combinatorial game questions, e.g.:
- surprising results: we had intuitive reasons to believe something as possible or not, but a theorem shatters that conviction and brings us on our knees, sometimes via pathological counter-examples. General surprise themes include:Lists:
- classification of potentially infinite sets like: compact manifolds, etc.
- problems that are more complicated in low dimensions than high like:
- generalized Poincaré conjectures. It is also fun to see how in many cases complexity peaks out at 4 dimensions.
- classification of regular polytopes
- unpredictable magic constants:
- why is the lowest dimension for an exotic sphere 7?
- why is 4 the largest degree of an equation with explicit solution? Abel-Ruffini theorem
- undecidable problems, especially simple to state ones:
- mortal matrix problem
- sharp frontiers between solvable and unsolvable are also cool:
- attempts at determining specific values of the Busy beaver function for Turing machines with a given number of states and symbols
- related to Diophantine equations:
- applications: make life easier and/or modeling some phenomena well, e.g. in physics. See also: explain how to make money with the lesson
Good lists of such problems Lists of mathematical problems.
Whenever Ciro Santilli learns a bit of mathematics, he always wonders to himself:Unfortunately, due to how man books are written, it is not really possible to reach insight without first doing a bit of memorization. The better the book, the more insight is spread out, and less you have to learn before reaching each insight.
Am I achieving insight, or am I just memorizing definitions?
Here is a more understandable description of the semi-satire that follows: math.stackexchange.com/questions/53969/what-does-formal-mean/3297537#3297537
You start with a very small list of:
- certain arbitrarily chosen initial strings, which mathematicians call "axioms"
- rules of how to obtain new strings from old strings, called "rules of inference" Every transformation rule is very simple, and can be verified by a computer.
Using those rules, you choose a target string that you want to reach, and then try to reach it. Before the target string is reached, mathematicians call it a "conjecture".
Since every step of the proof is very simple and can be verified by a computer automatically, the entire proof can also be automatically verified by a computer very easily.
Finding proofs however is undoubtedly an uncomputable problem.
Most mathematicians can't code or deal with the real world in general however, so they haven't created the obviously necessary: website front-end for a mathematical formal proof system.
The fact that Mathematics happens to be the best way to describe physics and that humans can use physical intuition heuristics to reach the NP-hard proofs of mathematics is one of the great miracles of the universe.
Once we have mathematics formally modelled, one of the coolest results is Gödel's incompleteness theorems, which states that for any reasonable proof system, there are necessarily theorems that cannot be proven neither true nor false starting from any given set of axioms: those theorems are independent from those axioms. Therefore, there are three possible outcomes for any hypothesis: true, false or independent!
Some famous theorems have even been proven to be independent of some famous axioms. One of the most notable is that the Continuum Hypothesis is independent from Zermelo-Fraenkel set theory! Such independence proofs rely on modelling the proof system inside another proof system, and forcing is one of the main techniques used for this.
The landscape of modern Mathematics comic by Abstruse Goose
. Source. This comic shows that Mathematics is one of the most diversified areas of useless human knowledge.Not to be confused with algebra over a field, which is a particular algebraic structure studied within algebra.
As mentioned at Human Compatible by Stuart J. Russell (2019), game theory can be seen as the part of artificial intelligence that deas with scenarios where multiple intelligent agents are involved.
Poet, scientists and warriors all in one? Conquerors of the useless.
A wise teacher from University of São Paulo once told the class Ciro Santilli attended an anecdote about his life:It turned out that, about 10 years later, Ciro ended up following this advice, unwittingly.
I used to want to learn Mathematics.But it was very hard.So in the end, I became an engineer, and found an engineering solution to the problem, and married a Mathematician instead.
It is hard to decide what makes Ciro Santilli more sad: the usage of Greek letters, the invention of new symbols, or the fifty million alternative font styles used.
Only Chinese characters could be worse than that!
Techniques to get numerical approximations to numeric mathematical problems.
The entire field comes down to estimating the true values with a known error bound, and creating algorithms that make those error bounds asymptotically smaller.
Not the most beautiful field of pure mathematics, but fundamentally useful since we can't solve almost any useful equation without computers!
The solution visualizations can also provide valuable intuition however.
Important numerical analysis problems include solving:
Ciro Santilli is actively looking for donations and contracts so he can continue to work full time on OurBigBook.com sustainably, and develop free hardcore university-level STEM education for all ages!
For 1M USD I will quit my job to work on OurBigBook for three more years to try and kickstart The Higher Education Revolution. Status: ~44k / 1M USD. MacArthur fellowship wink. At 4M USD I retire and work on open STEM forever.
I first quit my job 1st June 2024 to work on the project for 1 year after I reached my initial 100k goal mostly via a 1000 Monero donation. In this first year I improved project tech, but didn't go and solve university courses to create super targeted content, and didn't obtain a single contributing user except myself, see a summary at Section "OurBigBook Project Update March 2025". Day job total compensation as of August 2026 for reference: 205k USD/year. This may be inflated by the AI bubble. I try to keep the value up to date on LinkedIn: www.linkedin.com/in/cirosantilli/
For a followup, it would be an interesting experiment to spend on year full time solving as many courses as I can from a world class university in the city where I live in the UK, and adding that as content to the platform to see if that would attract interest, and reaching out directly to course takers at their university environment to try and help them. I intended to do that in year one but my got distracted by tech. It is quite possible that no one has ever done that before in history: a highly motivated technical person with the time and opportunity to do one single thing: help top university students learn their STEM courses better and have more fun doing so. I have in particular identified one course where this would be particularly feasible: the mathematics course, given that much of their course materials, and also their building are quite open. I do sometimes wonder if doing this would be just a waste of my life. But part of me tells me it could generate big interest and is worth a try. It would also be fun for you to watch me continue to commit career seppuku.
At 4M USD I retire and work on open STEM projects forever. At these timelines, I can't guarantee it will be specifically on education technology specifically all the way, but I guarantee that whatever it is it will be open and extremely well explained as usual.
It's necessary to be slightly underemployed if you are to do something significant - James Watson
Total donations to date ~144k USD. Donation breakdown:More details: Section "Accounting method"
- 2024-03-18: $126,352 (!!!): anonymous 1000 Monero donation to self-custody wallet. Further comments: Section "1000 Monero donation"
- 2024-03-13: $1,375: anonymous 10 Monero donation to self-custody wallet
- 2023-11-20: $14.563: anonymous 100 Monero donation to Binance wallet
- 2023-09: $810: anonymous 0.032 Bitcoin donation to Coinbase wallet
- subscriptions up to 2024-01: $143,795
Note to potential anonymous crypto donors: I live in the UK, and after some fun back and forth that included Barclays freezing my account for one week at one point, Barclays finally decided that they do not allow me to receive further anonymous donations. And I'm pretty sure that the same would happen on any other British bank sooner or later. Therefore, while I continue to accept anonymous donations, they will not count towards my "if I get X I do Y"-type donation goals, since I can't reliably spend that money. If you want to donate in crypto, and clearly give me your real identity and an explanation of how you got the money, then that is fine, it can count. Just be warned that I will need to give that information to my bank and clear it with them beforehand, and if they are still not happy with it, I'll just give it all back. Your identity does not have to be publicly disclosed, only the dates and amounts. But my bank has to know. Now, if you still want to donate a "retirement level amount" and treat me as a guinea pig in "find the best country for money laundering", well, go for it. But I make no promises! I don't want my children to grow up in shitcountries.
How to give:And if you have a different preferred payment mechanism not listed above, please contact Ciro, and he will set it up.
- one time donations:
- cryptocurrency: note that Ciro is not a regular crypto user, so you might want to make a smaller test donation and confirm that it worked by contacting Ciro before going for colossal amounts (one can dream):
- Monero address: 4A1KK4uyLQX7EBgN7uFgUeGt6PPksi91e87xobNq7bT2j4V6LqZHKnkGJTUuCC7TjDNnKpxDd8b9DeNBpSxim8wpSczQvzf. Secret view key: 7ccaf885ff5540b0ff18927e6ac5da30130afb1eaee09ad95d3c4536a6337e0f. This is a self-custody wallet on a "clean" dedicated Monero laptop connected the Internet. I check for incoming transactions from my dirty main laptop via a view-only wallet each weekend. The cash out method used is latest simplest thing that wasn't yet blocked in my country on a given week, the last time that was centralized swappers[ref]. The fact that the cash out method changes weekly confirms that Monero privacy hadn't yet been broken by countries and that Monero is still one of the most useful cryptocurrencies: Section "Are cryptocurrencies useful?". For transparency, I announce all non-trivial transactions on social media, and the full list of transactions can be seen by anyone with the secret view key provided. I previously had different addresses, so pre-existing donations on older addresses will not be visible there.
- Bitcoin address: 3KRk7f2JgekF6x7QBqPHdZ3pPDuMdY3eWR. This is a Coinbase wallet, off-chain transactions with no transaction fees accepted from other Coinbase users. This method has been tested, I have been able to receive funds from this address in 2023. Fees: non-fixed trading fees[ref] + 0% withdrawal fee on top of any Bitcoin network for on-chain transactions[ref]
- Ethereum address: 0x44cF8C9C015F46d3b2Df730b6492823FD7A91044. Test transaction recommended.
- Solana address: DjdaGawoVFdqxJEqpBGsSWuR4G4MVFNiNkAEu89HuKcE. Test transaction recommended.
- USDC address: 0x1dFABf2cdE6384f6Fdd4e6Dae3B9FA2d323e6F95
- TransferWise tag: wise.com/pay/me/cirod3. No fees apparently? Love it!
- PayPal: paypal.me/cirosantilli. Note that dots in Gmail address are ignored, and it is perfectly normal if the email you see has some extra dots in it. Fees: 2.9% + 0.30 GBP[ref].
- bank transfer: prove you are rich and you can have my bank details :-)
- cryptocurrency: note that Ciro is not a regular crypto user, so you might want to make a smaller test donation and confirm that it worked by contacting Ciro before going for colossal amounts (one can dream):
- monthly subscriptions of 1$/month or more on either:Symbolic 1 dollar/month donation are extremely welcome to signal your interest! This way if a certain critical mass of sponsors is ever reached (~100?), Ciro can start to more actively asking slightly higher amounts to really try to achieve full time self sufficiency.
- GitHub Sponsors: github.com/sponsors/cirosantilli. Fees: 0% for individuals, up to 6% for organizations[ref]
- Patreon: www.patreon.com/cirosantilli. Fees: 8% pro plan + 1% PayPal withdrawal capped at 20 USD[ref]. We are waiting to reach the cap to withdraw!
- larger grants/contracts from filthy rich individuals or organizations: contact Ciro as mentioned at: Section "How to contact Ciro Santilli" to discuss.Ciro is interested in contracts/voluntary work that would be compatible/synergic with the OurBigBook.com project. Some possibilities include:
- interacting directly with classes of university students to help them learn the class subject, while at the same time spreading the university knowledge outside of the university walls
- one-to-one mentoring of individuals of any age that are looking to make an impact in the world, and not just pass their exams
- fixing specific bugs in related projects Ciro has experience in. These could be either via one-off contracts, or on platforms such as:
Ciro's current ambitions require him to remain in developed countries, because Ciro wants to document advanced science and technology by liaising with top universities, and there is not nearly as much high technology in poor countries. Remaining in developed countries is also a required due to family reasons.
If you would like public acknowledgement for your support, Ciro will very gladly give it, just let Ciro know how you'd prefer it. Due to Ciro Santilli's campaign for freedom of speech in China, many supporters have chosen to be anonymous, and that is totally fine, not everyone is interested in politics, or has a situation where going public is acceptable, so we don't have a standard setup yet, let's build it together. A acknowledgement section at the bottom of this page would be a minimum, but I for larger donations we could add a your advertisement in a locations such as:
- near the top of of the accounts controlled by Ciro Santilli, e.g. one of Ciro Santilli's Twitter accounts, github.com/cirosantilli or stackoverflow.com/users/895245
- near the top of cirosantilli.com
The problem with education by Ciro Santilli
. Source. In this video Ciro Santilli exposes his fundamental philosophy regarding why Education is broken. This philosophy was the key motivation behind the failed OurBigBook Project.Intro to the OurBigBook Project
. Source. Maybe if he ever gets enough credibility, such opportunities would actually materialize. It could be a bit like Periodic Videos, but for molecular biology and physics, and backed by OurBigBook text/tree with minimal openly licensed videos. The fact that such opportunities are essentially impossible outside of the boredom of the university system is something we should really change about education.
Ciro Santilli has sometimes wasted time with low impact projects such as those listed at Ciro Santilli's minor projects instead of doing higher impact projects such as those mentioned at: Section "The most important projects Ciro Santilli wants to do".
But maybe "Everything you did brought you where you are now." applies, maybe it is during the "low impact activities" that one gets the inspiration and experience required for the "high impact ones".
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!
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-calculusArticles 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/derivativeVideo 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: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.
- 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
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 5. . 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. - Infinitely deep tables of contents:
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








