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This doesn't really explain why energy is needed in a blockchain. Every block contains a verifiable proof that energy has been used to mine the block. Given the
by Geee 4y ago
This doesn't really explain why energy is needed in a blockchain. Every block contains a verifiable proof that energy has been used to mine the block. Given the properties of the algorithm and physical reality, it is also a verifiable proof that certain amount of time has passed. This proof is what enables all participants to verify that the longest chain is the correct one.
Proof-of-work isn't used just to add cost, but to make sure that the longest chain has longest history in physical time, and make it objectively verifiable.
Proof-of-stake doesn't have this property. Whole history can be recreated in a microsecond, and there's no way to tell by looking at the blockchain. Instead, network participants have to ask others for the correct chain, or refer to a trusted source when there are disputes.
- dlubarov 4y agoI would argue that PoW participants still need to "ask others", albeit for different kinds of information - - For starters, if say I'm accepting a BTC payment, I need to ask a trusted source about the market value of BTC. - I need to ask which software I can trust to implement the Bitcoin protocol. - If I don't want to verify every transaction from the genesis, I need to ask for a checkpoint. - In case I'm being eclipsed, I need to ask whether the chain I'm seeing is the canonical one, or what approximate hash rate the canonical chain should have.
- Geee 4y agoThose things have a single truth, on which social consensus converges on. PoS doesn't have this single truth, and thus it's incapable of converging on it. "call a friend"-consensus fails when there are disputes.