I'm very excited about the launch of this paper which is part of a project Robin and I have been working on together. Today I hope to launch a demonstration that you can use bitcoin to compute a 64 bit division function.
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More details are provided on my github, where I'm also nearly finished with a proof-of-concept implementation of bitvm for bristol circuits:
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I've seen you (as in, on YT) code in sublime. And I thought that was impressive.
But this is so next level, I can't even.
To put it another way: I might know someone who knows someone who knows something about bristol circuits, if you catch my drift.
Thanks for the introduction!
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How much do I pay for 64b division? 😀
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The cost of a single transaction, if the BitVM paper is to believed
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well, 2. In the cooperative case there is a "funding" transaction and then a "settlement" transaction. In the dispute case there is also 1 or more "challenge" transactions and 0 or more "response" transactions.
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Wow! Sounds awesome! Congrats SuperTesnet!
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Interesting, reading it now.
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I read it. Although I don't understand everything, I think I prob get the gist of it.
If this becomes very widespread in use, and there need to be made ever more hashes to load these programs into the leaves, will the likely hood of collisions increase? And if so, can this be solved for by simple error-correction? Or maybe my questions doesn't make sense (i'm not very technical with computer stuff ;)
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Don't worry, the multiverse will run out of energy before we brute-force-search our way to a sha256 hash collision.
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Are you counting Marvel style 9 realms, or infinite multiverse? 😂
Either way congrats to the progress!
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Thanks for taking the time. I should've known that.
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Multiverse idk but for btc within its hash-horizon, it should suffice.
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idk if the question is even relevant.. so.. yeah sry. Trying to grok.
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ah! I was wondering how you got your demo out so fast!
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Holy shit it's a computer on Bitcoin.
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I wrote a post that hopefully unpacks BitVM: https://lightningnetwork.plus/posts/450 Please check and correct it if needed!
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Hmmm, this one's going to be interesting, seems like a whole lot of merkle tree style goodies are coming to bitcoin, wonder which one will really take hold as the front runner?
Always great to see people pushing for things that don't need consensus changes and waste time fighting with the community
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Good point! We can build many things on Bitcoin without soft forks.
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Here an explanation video on bitvm for people with limited technical knowledge. http://bit.ly/Bitvmtutorial
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I saw this elsewhere, came to post it here on stacker.news as soon as I started looking at it. Saw that you already posted it. Good job. Now I can go investigate it more...
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Bitcoin keeps getting better. Gold and Fiat keeps getting worse.
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While trying to understand the paper I did a simple explanation write-up https://github.com/fiksn/bitvm-explained
Feel free to add PRs to make this easier to grasp (or correct any mistakes I did).
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To reiterate, Bitcoin is now as Turing Complete as any other chain, and this requires zero changes to Bitcoin.
It’s become a canon maxi talking point that Turing Complete = Bad. This is silly for a number of reasons.
Firstly nothing in our reality will ever be TRULY Turing Complete, because the technical definition of Turing Complete actually requires an UNBOUNDED runtime, and we just don’t have an unbounded amount of space and time to accommodate for that.
Along the way a small cabal of script hackers such as @robin_linus and @super_testnet have figured out how to hack in all of the functionality we would want from a generalized computer into Bitcoin’s extremely limited OP set, so the only thing that has kept Bitcoin’s VM from being as Turing complete as something like Ethereum’s was not a matter of expressivity, but simply a matter of Runtime, with the most stringent limitation being the stack size limit.
All BitVM does is allow us to split the runtime of some logic that would be out of bounds of a single transaction ACROSS MULTIPLE TRANSACTIONS. That’s it. We aren’t adding any new semantic features, we just are exponentially increasing the length of the programs we can run.
So Bitcoin really isn’t any more Turing Complete by the technical definition as it was before, it simply has been given a runtime to its programs that we can reasonably say it’s “Turing complete enough” for any program that we could realistically want to execute.
Secondly this is the best thing possible for ossification. Why add in an Opcode when Bitcoin can already simulate any opcode imaginable? The debate now shifts to features to increase efficiency, privacy, security and not about features. Adding in this kind of functionality actually REDUCES risk for Bitcoin, precisely because it reduces the need for it to change in the future.
Thirdly being able to have satisfaction of arbitrary logical constraints means that you can cut out all kinds of trusted or semi-trusted escrow services that a version of Bitcoin without this requires. Congestion control/Coinjoin aggregators, sidechain quorums, certain types of DLC oracle type stuff all can go from trusted/semi trusted to 100% trustless. Bitcoin’s trustlessness is only as strong as the weakest link in the interaction you are engaging in with it. Oh and it means that Drivechains are unnecessary.
Finally this is opt-in. If you don’t trust your coins being locked to some Turing complete contract (totally reasonable) then don’t lock them to a Turing complete smart contract. One of beauties of the UTXO system is security sandboxing.
If people really feel strongly that Bitcoin shouldn’t have this functionality, perhaps for issues of incentives or something, that’s a conversation that should be had, but basically it would require ripping out Taproot, which seems very dumb at this point.
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I can't understand shit but I have the feeling that Turing Completeness didn't allow shit on Eth and that it will be the same on Bitcoin
We are seeking, uncensorability, scalibility, immutability of a digital asset nothing more, and Bitcoin is almost there already.
I feel strong shitcoinery here even if I don't really care since the consensus rules are kept untouched. And I'm also and happy that this innovation completely destroys the narrative of obvious high time pref stupid enemies of Bitcoin like Udi, Eric, and their kliq who want to change Bitcoin whenever they find a new fancy useless shit to build on Bitcoin.
Finally we should all get the obvious strong warning here. Taproot unlocked things (and it is maybe far from over) that nobody could have imagined before. So we should be extremely careful when we will decide to activate CTV or any form of covenants on Bitcoin IMHO We have to take all the time necessary and stop being pressured by Bitcoin enemies
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To be more precise it didn’t unlock things that people couldn’t imagine, all those changes were intentional. What people didn’t imagine was how those changes would be used. Most core devs didn’t spend too much time worrying about ordinals because the system was still functioning as expected
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Very impressed with stacker news comments today. Would have expected everyone to flip out about this.
Very excited to see what BitVM brings.
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From a theoretical computer science standpoint I am really excited. In practice I don't think this will change much. First and foremost bitcoin is a store of value, competing with real estate and gold. And in the end no one asks whether either of those bricks can be used to emulate a turing machine or not.
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Barely understand, but I'm down for bitcoin chess contracts
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Absolutely brilliant. Need to share more about this. Known about this for quite awhile from super, but we need more building!
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Am I the only one who thinks Bitcoin does not need to be a decentralized compute like shitcoins?
Like, idgaf what people pay their vbytes for. But some usecases just don't need to be on the hardest money in the world settlement layer?
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What is this wizardry?
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Prediction markets when
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BitVM falks doing a good job there. Honestly, I'm a NOOB here...