Post-quantum cryptography (PQC), like Falcon signature schemes, are designed to withstand quantum attacks, but their current inefficiencies make signatures costly on Ethereum

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Quantum computing threatens all cryptocurrency networks that rely on current cryptographic standards, though experts disagree on the timescale of viable attacks. Some post-quantum methods, such as Falcon signature schemes, provide resistance against quantum computing-enabled attacks, but certain inefficient functions currently make the signatures expensive on Ethereum.