Evil demon Updated 2025-07-16
Genesis block message Updated 2025-07-16
Inscription added by Satoshi Nakamoto on the Genesis block containing:
The Times 03/Jan/2009 Chancellor on brink of second bailout for banks
which is a reference to: www.thetimes.co.uk/article/chancellor-alistair-darling-on-brink-of-second-bailout-for-banks-n9l382mn62h wihch is fully titled:
Chancellor Alistair Darling on brink of second bailout for banks
The "Alistair" was slikely removed due to limited payload concerns.
Through the newspaper reference, the message proves a minimal starting date for the first mine.
And it hints that one of Bitcoin's motivation was the financial crisis of 2007-2008, where banks were given bailouts by the government to not go under, which many people opposed as the crisis was their own fault in the first place. A notable related stab is taken at Len Sassaman tribute.
We can extract the image from the blockchain ourselves by starting from: blockchain.info/block-height/0?format=json.
From that page we manually extract the hash 000000000019d6689c085ae165831e934ff763ae46a2a6c172b3f1b60a8ce26f and then:
wget -O 0.hex https://blockchain.info/block/000000000019d6689c085ae165831e934ff763ae46a2a6c172b3f1b60a8ce26f?format=hex
xxd -p -r 0.hex
and that does contain the famous genesis block string:
EThe Times 03/Jan/2009 Chancellor on brink of second bailout for banks
The JSON clarifies that the data is encoded in the script field of the transaction input:
{
      {
         "script":"04ffff001d0104455468652054696d65732030332f4a616e2f32303039204368616e63656c6c6f72206f6e206272696e6b206f66207365636f6e64206261696c6f757420666f722062616e6b73"
The extra E (0x45 in ASCII) in EThe Times is just extra noise required by the script, we can break things up as:
04ffff001d0104 45 5468652054696d65732030332f4a616e2f32303039204368616e63656c6c6f72206f6e206272696e6b206f66207365636f6e64206261696c6f757420666f722062616e6b73
where:
  • 54 is T
  • the 04ffff001d0104 part just doesn't show up on the terminal because it is not made of any printable characters.
The initial 04 is OP_RETURN.
TODO what is actual the meaning of the ffff001d010445 part? @defango twitter.com/defango/status/1642750851134652417 comments:
04ffff001d0104 is a hexadecimal string. It is commonly used in the Bitcoin network as a part of the mining process. Specifically, it is used as the target value for a block to be considered valid by the Bitcoin network.
This value represents the level of difficulty required for a miner to generate a block that meets the network's criteria. The first four bytes, 04ffff, represent the maximum possible target value. The next three bytes, 001d01, represent the current difficulty level
while the final byte, 04, is a padding byte. In summary, this value sets the difficulty level for mining a new block in the Bitcoin network.
TODO the output of the transaction has a jumbled script, likely just a regular output to get things going, can't be arbitrary like input.
Neon lamp Updated 2025-07-16
The impact of the work is greater when you examine what one single new technology would do to existing society, as in Primer (2004), rather than "start on a society with severl new technologies", like in Star Wars.
Ciro Santilli is a big believer that there is value in tutorials written by beginners, because beginners are more likely to explain things in a way that other beginners can understand.
Even though they make more mistakes, this more approachable point of view can be very valuable.
And mistakes/omissions can be corrected on comments by people with more knowledge, so that the writer also ends up learning something new.
By other people:
  • jakobschwichtenberg.com/about/ from Jakob Schwichtenberg mentions quotes C. S. Lewis book "Reflections on the Psalms"[ref]:
    It often happens that two schoolboys can solve difficulties in their work for one another better than the master can. [...] The fellow-pupil can help more than the master because he knows less. The difficulty we want him to explain is one he has recently met. The expert met it so long ago he has forgotten. He sees the whole subject, by now, in a different light that he cannot conceive what is really troubling the pupil; he sees a dozen other difficulties which ought to be troubling him but aren't.
Thermodynamic potential Updated 2025-07-16
chemistry.stackexchange.com/questions/7696/how-do-i-distinguish-between-internal-energy-and-enthalpy/7700#7700 has a good insight:
To summarize, internal energy and enthalpy are used to estimate the thermodynamic potential of the system. There are other such estimates, like the Gibbs free energy G. Which one you choose is determined by the conditions and how easy it is to determine pressure and volume changes.
The simplest multicellular species Updated 2025-07-16
One of the simplest known seems to be: en.wikipedia.org/wiki/Trichoplax
www.u-tokyo.ac.jp/focus/en/articles/a_00220.html "The simplest multicellular organism unveiled" from 2013 mentions Tetrabaena socialis.
Then of course: Caenorhabditis elegans is a relatively simple and widely studied model organism.
Video 1.
Nicole King (UC Berkeley, HHMI) 1: The origin of animal multicellularity by iBiology (2015)
Source.
Daniel Sank Updated 2025-07-16
Started at Google Quantum AI in 2014.
Has his LaTeX notes at: github.com/DanielSank/theory. One day he will convert to OurBigBook.com. Interesting to see that he is able to continue his notes despite being at Google.
Diffraction Updated 2025-07-16
Excretion Updated 2025-07-16
Existence and uniqueness Updated 2025-07-16
Existence and uniqueness results are fundamental in mathematics because we often define objects by their properties, and then start calling them "the object", which is fantastically convenient.
But calling something "the object" only makes sense if there exists exactly one, and only one, object that satisfies the properties.
One particular context where these come up very explicitly is in solutions to differential equations, e.g. existence and uniqueness of solutions of partial differential equations.
Seemed to just work at 68bbadfd77f679f0df0fcd0de5bceb9c37b1144a Ubuntu 20.10, was forked from parent project in 2018.

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