satoshi@vistomail.com by Ciro Santilli 40 Updated 2025-07-16
One of Satoshi's email addresses, it's how he made the First public announcement of Bitoin on first public announcement of Bitcoin on 2008-10-31.
At some point later on vistomail.com was discontinued and acquired by a super dodgy dude, Alex Elbanna, so it hasn't been Satoshi for a while.
Propositional logic by Ciro Santilli 40 Updated 2025-07-16
This is the part of the formalization of mathematics that deals only with the propositions.
In some systems, e.g. including Metamath, modus ponens alone tends to be enough, everything else can be defined based on it.
Erik Finman by Ciro Santilli 40 Updated 2025-07-16
www.unilad.com/technology/erik-finman-bitcoin-12-year-old-millionaire-invest-798094-20231207
In 2011, Finman made a deal with his parents that he would not pursue a college degree as he wanted to make his fortune outside of traditional education.
After receiving $1,245 from his grandmother that year, Finman invested into Bitcoin (BTC) - which was then trading at around $12 - and this gave him about 103 BTC.
Shame that he seems to be a American exceptionalism idiot. Perhaps it was inevitable given his circonstances. After a small market crash: x.com/erikfinman/status/1820457023013626322.
Opportunities like this come across only once every few years.
This ain’t financial advice…
But if you got the cash.
Never bet against America
If is the change of basis matrix, then the matrix representation of a bilinear form that looked like:
then the matrix in the new basis is:
Sylvester's law of inertia then tells us that the number of positive, negative and 0 eigenvalues of both of those matrices is the same.
Proof: the value of a given bilinear form cannot change due to a change of basis, since the bilinear form is just a function, and does not depend on the choice of basis. The only thing that change is the matrix representation of the form. Therefore, we must have:
and in the new basis:
and so since:
Dot product by Ciro Santilli 40 Updated 2025-07-16
The definition of the "dot product" of a general space varies quite a lot with different contexts.
Most definitions tend to be bilinear forms.
We use the unqualified generally refers to the dot product of Real coordinate spaces, which is a positive definite symmetric bilinear form. Other important examples include:
The rest of this section is about the case.
The positive definite part of the definition likely comes in because we are so familiar with metric spaces, which requires a positive norm in the norm induced by an inner product.
The default Euclidean space definition, we use the matrix representation of a symmetric bilinear form as the identity matrix, e.g. in :
so that:
medium.com/left-right/the-education-system-is-about-to-implode-5c95f774b523 The Education System is About to Implode by Nicholas Budny (2020)
Stanford, MIT, Harvard and Oxford are luxury goods in the same sense that a Mercedes-Benz might be, or the latest iPhone. They sell an aesthetic experience that provides the consumer with social status, similar to acquiring expensive clothes or a fancy house.
Video 1.
Bar scene from Good Will Hunting
. Source. This scene is way way overdone. But:
Hero: You wasted $150,000 on an education you coulda got for $1.50 in late fees at the public library.
Bad guy: Yeah, but I will have a degree. And you'll be serving my kids fries at a drive-through on our way to a skiing trip.
TODO application.
TODO speedup over algorithm for general matrices.
www.studentclustercompetition.us/ comments:
The HPCG benchmark uses a preconditioned conjugate gradient (PCG) algorithm to measure the performance of HPC platforms with respect to frequently observed but challenging patterns of computing, communication, and memory access. While HPL provides an optimistic performance target for applications, HPCG can be considered as a lower bound on performance. Many of the top 500 supercomputers also provide their HPCG performance as a reference.
Every invertible matrix can be written as:
where:
Note therefore that this decomposition is unique up to swapping the order of eigenvectors. We could fix a canonical form by sorting eigenvectors from smallest to largest in the case of a real number.
Intuitively, Note that this is just the change of basis formula, and so:
ASCII art of a Force of Will, a famous and powerful Magic: The Gathering card first printed in 1996.
This is Ciro Santilli's personal favorite ASCII art he has found in the blockchain so far. Also Ciro could not find any other previous source of this, so there is some chance it is original. One can dream.
The choice of card is probably linked to the function of the card in the game of Magic: The Gathering. This card essentially prevents the opponent from casting a spell they are about to cast. The presumed intended meaning of this art is further accentuated by the old card type term "interrupt" (late renamed to "instant"), which suggests that "this ASCII art is an interruption to the normal monetary transactions of the blockchain".
One of also reminded of the prayer wars interruption attempts. We could not however identify anything specific that this ASCII art might have tried to interrupt besides the normal flow of monetary transactions.
If one goes full art critic mode, it is also tempting to draw a parallel between the card's "You may pay 1 life" alternative casting cost (as opposed to 5 mana, 3 and two blue, which is a very large cost for most games) as being a reference to the money spent by the uploader of the art to upload it.
TODO understand exactly how it was encoded and why it is so weird. The UUUU has a slightly weird encoding which we fixed by hand here TODO understand.
 -------------------------------------
|  Force of Will               3 U U  |
|  ---------------------------------  |
| |                  ////////////   | |
| |                ////() ()\////\  | |
| |               ///_\ (--) \///\  | |
| |        )      ////  \_____///\\ | |
| |       ) \      /   /   /    /   | |
| |    ) /   \     |   |  /   _/    | |
| |   ) \  (  (   /   / /   / \     | |
| |  / ) ( )  / (    )/(    )  \    | |
| |  \(_)/(_)/  /UUUU \  \\\/   |   | |
| .---------------------------------. |
| Interrupt                           |
| ,---------------------------------, |
| | You may pay 1 life and remove a | |
| | blue card in your hand from the | |
| | game instead of paying Force of | |
| | Will's casting cost.  Effects   | |
| | that prevent or redirect damage | |
| | cannot be used to counter this  | |
| | loss of life.                   | |
| | Counter target spell.           | |
| `---------------------------------` |
|                                     l
| Illus.  Terese Nelsen               |
 -------------------------------------
Figure 1. Source. A high resolution scan of the original card depicted in the ASCII art for comparison.
The following two ASCII transactions:
tx 0f05c47a8caafadecc10d70ba3bf010eaf6bb416b5e1ad7b01cf3445f5fb7a1c
I am. Therefore, I have come to be.

-- Hyena


tx e6d48f6912929a58a2ee30c13768058777d8547215c27109b5cb0724e7abaaba
Erich,
Bro, this looks excellent!!
-Duriel
suggest this ASCII art might have been uploaded by Figure "Erich Erstu", AKA Hyena, creator of cryptograffiti.info, a service which would have allowed uploading ASCII content to the blockchain.
The only other mention of "Duriel" in the blockchain is tx 140562ceb42fc8943fa52ccc0ddbb11ca2d88dae9b5240d7a4b46864538c515a which has some freedom of speech comments and gives the email:
Duriel@paystamper.com = 1HcuhfTAiQCt6KdMG2rZLXsTcKYj9nLDhS
paystamper.com was some other blockchain service from circa 2015:
All found so far are also reproduced at: asciiart.website/index.php?art=people/naked%20ladies therefore not blockchain original.
Some of the very first ASCII art present in the blockchain besides BitLen is porn. Surprising?

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!
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    Screenshot of the "Derivative" topic page
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    Figure 2.
    You can publish local OurBigBook lightweight markup files to either https://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.
  3. https://raw.githubusercontent.com/ourbigbook/ourbigbook-media/master/feature/x/hilbert-space-arrow.png
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    Figure 6.
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    .
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All our software is open source and hosted at: github.com/ourbigbook/ourbigbook
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Feel free to reach our to us for any help or suggestions: docs.ourbigbook.com/#contact