leanVM quantum-resistant proofs, execution proofs built from hashes alone

Strawmap I* (2028) · leanVM PQ proofs

This item shows, with a hash-based proof that is hard to break even for quantum computers, that the result processed by leanVM, the simple execution virtual machine Ethereum is pursuing, is correct.

Why it is needed

Today every Ethereum node re-executes each transaction in a block one by one and checks the result. This is safe, but nodes have a lot to do, which makes it hard to make blocks bigger. So the direction is to skip re-executing transactions and instead check only a short proof (zero-knowledge proof) that execution finished correctly. However, many of the proof systems in wide use today rely on elliptic curve cryptography. Elliptic curve cryptography can be broken once a sufficiently large quantum computer exists. If a proof can be forged, everyone would believe an incorrect state to be correct, so the proof system must withstand quantum computers. This item aims to build and verify post-quantum proofs that use only hash functions, on top of leanVM, the simple execution virtual machine the Ethereum Foundation is pursuing under the name Lean Ethereum. Hash-based proofs are known to be hard to break even with quantum computers. On leanVM, which has few instructions and a simple structure, producing proofs is also easier. However, the I* slot in the Strawmap is only an estimated position. This item is still at the research stage, so its content may change or it may be dropped.

How it works

  1. Execute transactions in leanVM The party producing the proof executes the transactions in the block on leanVM, the simple virtual machine, and obtains the result.
  2. Build the proof from hashes alone It summarizes the execution mathematically and produces a short proof that this execution is correct, using only hash functions instead of elliptic curves.
  3. Nodes only check the proof Other nodes verify only the proof without re-executing transactions. Because it is hash-based, the proof is hard to forge even once quantum computers arrive.

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