Pikachu: Securing PoS Blockchains from Long-Range Attacks by Checkpointing into Bitcoin PoW using Taproot. (arXiv:2208.05408v1 [cs.CR])

Blockchain systems based on a reusable resource, such as proof-of-stake
(PoS), provide weaker security guarantees than those based on proof-of-work.
Specifically, they are vulnerable to long-range attacks, where an adversary can
corrupt prior participants in order to rewrite the full history of the chain.
To prevent this attack on a PoS chain, we propose a protocol that checkpoints
the state of the PoS chain to a proof-of-work blockchain such as Bitcoin. Our
checkpointing protocol hence does not rely on any …

attacks bitcoin blockchains pos