Bitcoin faces a practical scaling problem if quantum computing forces a migration to post-quantum cryptography. Post-quantum signatures are substantially larger than current ECDSA signatures, creating two divergent paths forward.

The first solution involves increasing Bitcoin's block size. Current blocks cap at 1MB, constraining transaction throughput. Larger blocks would accommodate bulkier quantum-resistant signatures without reducing transaction capacity. However, this approach resurrects the block size debate that fractured the community in 2017. Bigger blocks raise node running costs and create centralization pressures, potentially concentrating validation power among well-capitalized operators.

The alternative leverages zero-knowledge STARK proofs for signature aggregation. STARK (Scalable Transparent Argument of Knowledge) technology allows multiple signatures to be compressed into a single cryptographic proof. This keeps block sizes manageable while verifying transaction authenticity. STARKs avoid the trusted setup phase required by some zero-knowledge schemes, making them philosophically aligned with Bitcoin's trustless ethos.

STARKs introduce their own complexity. Proof generation demands significant computational resources, shifting verification work from network nodes to transaction creators. The proving infrastructure must mature substantially before mainnet deployment becomes viable. Integration also requires substantial protocol changes and community consensus.

The quantum timeline remains uncertain. Cryptographers estimate 10-20 years before quantum computers threaten Bitcoin's elliptic curve security. This window allows thorough research and testing, but not indefinite delays. The network must settle on a migration strategy long before quantum threats materialize.

Block size increases favor simpler implementation but sacrifice Bitcoin's node accessibility. STARK aggregation preserves decentralization but demands years of cryptographic R&D and engineering work. Neither option gains obvious consensus among developers and miners.

Bitcoin's response will likely combine both approaches. Moderate block size increases could accompany a phased transition to quantum-resistant