Concurrent programming course of the University of Oxford Updated 2025-07-16
Computer science course of the University of Oxford variant Updated 2025-07-16
Open source text-to-image model Updated 2025-07-16
Radio transceiver Updated 2025-07-16
Raised and lowered indices Updated 2025-07-16
TODO what is the point of them? Why not just sum over every index that appears twice, regardless of where it is, as mentioned at: www.maths.cam.ac.uk/postgrad/part-iii/files/misc/index-notation.pdf.
Those in indices on bottom are called contravariant vectors.
It is possible to change between them by Raising and lowering indices.
The values are different only when the metric signature matrix is different from the identity matrix.
Computer science masters course of the University of Oxford Updated 2025-07-16
Binutils utility Updated 2025-07-16
Cool data embedded in the Bitcoin blockchain AtomSea & EMBII Updated 2026-04-05
"AtomSea & EMBII" refers to an upload system for various media types includeing text, images, HTML pages and audio.
The name "AtomSea & EMBII" is a reference to the online handles of its creators. That string appears to be added as padding in the protocol and is therefore visible repeatebly in the blockchain, though it is sometimes cut up a bit. The following online profiles of the creators feel authentic:
Tried saying hi to them at: twitter.com/cirosantilli/status/1382080760774033415 and they replied: twitter.com/AllenVandever/status/1563964396656812034
The feature-set of their protocol is impressive:Basically they've created a fully descentralized Bitcoin-based social media. Their system is basically a sligly more clunky superset of Ordinal ruleset inscriptions, just way older and way less known for whatever reason.
- various media formats:
- multipage setups:
The Mahabharatabitfossil.org/root/0618f12af65a4e82f8e7b41f8578721dfeb109e9a73ff71aebdbc982696e3720/
Figure 1. Illustration for The Mahabharata inscription. - image galleries: bitfossil.org/root/ae8d3b46b934bedc363e11abe8c8607171994470957c286274f699a0b3a9bbd7/index.htm
- audio:
Spock_Live_Long_And_Prosper.mp3bitfossil.org/root/1bc87dbff1ff5831287f62ac7cf95579794e4386688479bab66174963f9a4a0c/index.htm
- social fetures:
- author photo below post via signture! bitfossil.org/root/738ab32bf82e3e0d4d2b29e40ad194cbbef6685d0116e94371e3cef4992349c8/index.htm (testnet) See the
SIGNED BYwith EMBII's photo! This feature was added in January 2015[ref]- For example, this lists the buy and sell orders for Figure "
YellowRobot.jpg": p2fk.io/GetObjectByAddress/17mdB8cVCQVhBi46bF43JpniZ4DAgE3JjH?mainnet=true&verbose=trueThe NFT system was retroactively added on top of signatures, it didn't exist at the time signatures were added. The first listing was made on December 2023[ref]:Inscriptions without signature such as those from before signatures were added can be claimed by the first person who claims them without any cryptographic proof[ref]:unsigned URN can be claimed and traded by the first who try they are basically free for all public domain
Figure 2. . Source. tx 4c7d8f6e7082a30d2d2d07c47ab462ea389415f4b95559106ff5f83f2bca8c82 (March 2015) seems to have a summary of the system. It shows in particular the cross-blockchain mechanism that mad EMBII implemented.creation.jpg
- sending messages to other people. TODO example.
- voting. TODO example.
- author photo below post via signture! bitfossil.org/root/738ab32bf82e3e0d4d2b29e40ad194cbbef6685d0116e94371e3cef4992349c8/index.htm (testnet) See the
- tooling:
- bitfossil.org is an indexer website for the inscriptions. For example bitfossil.org/67b2facfd8160d4fa11b02829b6387d07537b57a7a24f19b029b2a5ae7b81830/ displays Figure "
YellowRobot.jpg" which was inscribed at toplevel transaction tx 67b2facfd8160d4fa11b02829b6387d07537b57a7a24f19b029b2a5ae7b81830. Functionality seems a bit limited compared to the local clients however, e.g. you can't see all uploades by a given author. - apertus.io/ TODO vs Sup? At x.com/EMBII4U/status/1929498259883536886 EMBII tries to explain it but not sure.
Each P2FK inscription is done over P2FKH payloads. Each inscription a toplevel transaction which links to other transactions. All the linked transactions together make up the payload. The most common payload type is a text plus image, as is the case of Nelson-Mandela.jpg, which can be seen at bitfossil.org/root/78f0e6de0ce007f4dd4a09085e649d7e354f70bc7da06d697b167f353f115b8e/ where
78f0e6de0ce007f4dd4a09085e649d7e354f70bc7da06d697b167f353f115b8e is the toplevel transaction ID: www.blockchain.com/btc/tx/78f0e6de0ce007f4dd4a09085e649d7e354f70bc7da06d697b167f353f115b8e See Section "Nelson-Mandela.jpg" for a detailed reverse engineering of the format, and Section "AtomSea & EMBII data format" for a summary of it.The system shows the messages and the images on a single page: bitfossil.org/root/4cbb32cd27b5b5edc12d3559bdffc1355ac2a210463d5cfaadc7ce9b06675b2b/index.htm It is basically a blockchain-based Twitter.
Somewhat related projects:
At twitter.com/EMBII4U/status/1762501350997233976 (2024) EMBII mentions that he was inspired by the Satoshi uploader.
Computer mouse Updated 2025-07-16
Rigid body dynamics simulator Updated 2025-07-16
Cool data embedded in the Bitcoin blockchain Taproot Wizards Updated 2025-07-16
www.coindesk.com/tech/2024/01/12/taproot-wizards-bitcoin-ordinals-project-that-raised-75m-to-sell-quantum-cats-collection/:OMG if only the worlds wouldn't invest in such useless crap... it would probably be a better and more boring world.
Cool data embedded in the Bitcoin blockchain Largest ordinal inscription Updated 2025-07-16
We can get a list of the ordinals at: archive.org/details/bitcoin-ordinal-inscriptions.csv and then sort them by payload size with:
sort -k6 -n -t, ordinals.csv -o ordinals-sort-size.csvThis shows to us that as of block ~831k, there are 4 ordinals which are far far larger than any other between 3 MiB and 4 MiB, at about 10x larger than then 5th one d115a6e689086fd587e5032f24ba2a8c01f2f87cba758c9d5eb8cf7f6e9a816a
In those cases, a single inscription takes almost the entire block, and the inscribers must have had direct dealings with their mining pool:
- ordinals.com/inscription/4af9047d8b4b6ffffaa5c74ee36d0506a6741ba6fc6b39fe20e4e08df799cf99i0: 3,946,469 bytes (image/jpeg). Bitcoin Magazine cover showing the face of Julian Assange. tx 4af9047d8b4b6ffffaa5c74ee36d0506a6741ba6fc6b39fe20e4e08df799cf99 block 786501 (2023-04-22). Mined by Terra Pool.
- ordinals.com/inscription/0301e0480b374b32851a9462db29dc19fe830a7f7d7a88b81612b9d42099c0aei0: 3,915,537 bytes (image/jpeg). Taproot Wizards ad. This was apparently the largest block ever mined at the time: www.reddit.com/r/Bitcoin/comments/10r6t1l/the_first_4_mb_block_in_bitcoin_history_mined_by/ and received some notice. tx 0301e0480b374b32851a9462db29dc19fe830a7f7d7a88b81612b9d42099c0ae block 774628 (2023-02-01). Mined by Luxor pool.
- ordinals.com/inscription/79b91e594c03c8f06d70c44a288a88a413c540abca007829ca119686a7f979dai0: 3,878,842 bytes (image/webp). "Bitcoin War Bonds". A spoof of something. No time to understand now. tx 79b91e594c03c8f06d70c44a288a88a413c540abca007829ca119686a7f979da block 777945 (2023-02-23). Mined by Terra Pool.
- ordinals.com/inscription/b5a7e05f28d00e4a791759ad7b6bd6799d856693293ceeaad9b0bb93c8851f7fi0: 3,379,682 bytes (video/mp4). Short looping video of a "purple frog drinking from a glass with a straw". Yes you heard that right. TODO context? tx b5a7e05f28d00e4a791759ad7b6bd6799d856693293ceeaad9b0bb93c8851f7f block 776884 (2023-02-16 ) Despite being huge, this received very little attention, the only Google mention is at An overview of recent non-standard Bitcoin transactions by 0xB10C. Mined by Terra Pool.
Ciro Santilli's hardware SanDisk Ultra Flair 64 GB Updated 2025-07-16
Cool data embedded in the Bitcoin blockchain Nelson-Mandela.jpg Updated 2026-04-05
bitfossil.org/root/78f0e6de0ce007f4dd4a09085e649d7e354f70bc7da06d697b167f353f115b8e/ in block 273536 (2013-12-07).
This is one of the earliest AtomSea & EMBII uploads.
Nelson-Mandela.jpg"There is nothing like returning to a place that remains unchanged to find the ways in which you yourself have altered." - Nelson Mandela Nelson Rolihlahla Mandela was a South African anti-apartheid revolutionary, politician and philanthropist who served as President of South Africa from 1994 to 1999. - Wikipedia Born: July 18, 1918, Mvezo, South Africa Died: December 5, 2013.
Stefan Thomas Updated 2025-07-16
www.nytimes.com/2021/01/12/technology/bitcoin-passwords-wallets-fortunes.html
As for his lost password and inaccessible Bitcoin, Mr. Thomas has put the IronKey in a secure facility - he won’t say where - in case cryptographers come up with new ways of cracking complex passwords. Keeping it far away helps him try not to think about it, he said.
“I would just lay in bed and think about it," Mr. Thomas said.
Star Trek character Updated 2025-07-16
Bitcoin implementation Updated 2025-07-16
Stacks Project Updated 2025-07-16
- Renders: stacks.math.columbia.edu/. HTML is one tiny section per page, making it unreadable.
- LaTeX source: github.com/stacks/stacks-project
The book is very dry, extremelly boring unfortunately. Definition and theorem only for the most part.
Ganesh Sittampalam Updated 2025-07-16
Sexual innuendo Updated 2025-07-16
There are unlisted articles, also show them or only show them.