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Comment by Dzugaru | Hacker News Reader

> Ethereum will use dramatically less carbon to be more secure

Why is that? PoS security model is fundamentally different from PoW - for instance - you cannot determine which of the two chains is "correct" anymore, you have to consult "a friend" [0]. That's not the case in Bitcoin, where the correct chain is simply the longest.

All PoS algos are very complex and have a ton of seemingly bandaid solutions for various problems that arise when you can create alternate histories freely (even if you use VDFs I think), and there is a disturbing lack of critique on that. So, why is it seen as "more secure"?

[0] https://yanmaani.github.io/proof-of-stake-is-a-scam-and-the-...

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If the most-difficult chain wins, period, then Bitcoin is completely controlled by the miners. Nobody else has any say over consensus rules, and even if the miners violated the rules to mint themselves extra money, they would still have the "correct chain" if it had the most accumulated hashpower.

If the correct chain is actually the most difficult chain that follows the accepted rules, then you're still checking with a friend to find out what software implements the correct rules.

Most bitcoin people tell me the latter is the actual case, which means there's a level of social consensus for PoW as well as PoS.

There's multiple levels of consensus. Chain consensus is what determines the correct chain, given the current rules. Miners work under these rules.

Consensus on which rules to use happens on a different level. I'd say that it's economic consensus enforced by network participants. There's economic incentive to use rules which will not split the network.

Right, so you're telling me it's the latter case.

That means you can't tell what the correct chain is just by counting hashes. You have to ask someone what the currently correct software is, and then you can find the correct chain for that software.

This puts you in the same position as someone on a proof-of-stake chain.

That's not really how it works either. Everyone makes decisions individually based on their understanding of the best rules and also tries to keep the network from splitting. There aren't any competing chains, because issues are debated and solved externally. If this consensus fails, then the network splits and there's a fork. After that, everyone can choose either Bitcoin or Bitcoin Cash. Neither of them is "correct". Everyone chooses whichever version they like most. I call this economic consensus, because I believe that this consensus tries to find rules which would maximize long-term economic demand for the currency.

This is completely different issue than chain consensus disputes, which means that inside the chosen rules there's disputes on which history is correct. I.e. it's the double-spend problem, which PoW solves. PoS is subjective, and it's impossible to determine the correct history without asking someone. [0]

[0] https://hugonguyen.medium.com/proof-of-stake-the-wrong-engin...

By "correct," I mean the chain used by the community I'm interested in. To know that, I have to ask a member of that community for the correct software.

Honestly, the thing kinda breaks if you have several sets of rules aka Bitcoin clones. No, ideally, the thing works if you have > 50% computation resources of the planet consumed (and of course, controlled) by miners using one set of rules. This way you cannot have competing chains at all, and the correctness of the set of rules is kinda obvious - they're correct if they make sense to me (paying arbitrary rewards to oneself does not make sense, obviously) - no need to ask anyone - I see an enourmous chain with enourmous burned computation and I see the code.

In this sense there could only be Bitcoin. PoS cannot come close to that at all.

P.S. To clarify a bit more - I don't think the most-difficult chain can be with broken nonsensical rules, not in the long term.

I concede that PoS is not as secure as a hypothetical future Bitcoin consuming over half the computation on the planet. That would also have the advantage of making 51% attacks flatly impossible.

Compared to Bitcoin as it exists in the real world, PoS has advantages.

Choosing between Bitcoin and Bitcoin Cash is a completely different matter. You choose whichever you like, and you can verify yourself that the software follows those rules. There's no chance that users wouldn't converge into their chosen blockchain, because both forks follow the longest chain in their forks.

You assume that the community somehow can agree which chain is the correct one in proof-of-stake. This is not true because there's no longest chain rule. Without an authority, users would never be able to converge into the same chain, after a split has happened.

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