Bitcoin's Quantum Future: ZK STARKs vs Block Size Increase

The future of Bitcoin's security in a post-quantum world is becoming increasingly important as experts weigh the options for keeping the blockchain secure. StarkWare co-founder Eli Ben-Sasson believes that Zero-Knowledge (ZK) STARKs are the way to go, reducing the size of large post-quantum signatures and allowing for more transactions per second.

Ben-Sasson claims that increasing Bitcoin's block size is a blunt fix that could lead to centralization, and argues that ZK STARKs can handle the issues created by making Bitcoin quantum-safe while also reaching mass adoption. Blockstream founder Adam Back agrees with Ben-Sasson on this point.

According to Marin Ivezic, author of PostQuantum.com and founder of Applied Quantum, SegWit reduced the impact of large signatures by up to 75%, but his modeling of NIST's ML-DSA-44 scheme suggests that block capacity would be around 500 to 700 transactions, down from 2,500 to 3,000 today.

Other solutions being explored include compressing post-quantum signature schemes and using ZK proof aggregation. However, Ivezic warns that Bitcoin governance is the sticking point, with many in favor of a simple block size increase due to its ease of implementation.