lean Ethereum Part 2: PQ Signatures and Poseidon with Dmitry and Benedikt

https://www.youtube.com/watch?v=xh8hbz1nqxQ In this episode, Nico Mohnblatt speaks with Benedikt Wagner and Dmitry Khovratovich, cryptography researchers at the Ethereum Foundation, for the second instalment of the lean Ethereum miniseries. They explore leanSig, a hash-based multi-signature scheme designed as a post-quantum replacement for BLS in Ethereum consensus. The conversation walks through how one-time signatures and Merkle trees can be combined to support long-lived validators, and why SNARK-based aggregation is needed in a post-quantum setting. The talk touches on key tradeoffs like signature size versus verification speed, encoding challenges behind their At the Top of the Hypercube work, and the role of Poseidon as the core hash function. Related Links

• lean Ethereum Part 1: Introduction with Justin Drake
• lean Ethereum
• Lean Consensus R&D Progress
• leanSig Implementation
• Poseidon2: A Faster Version of the Poseidon Hash Function
• At the Top of the Hypercube – Better Size-Time Tradeoffs for Hash-Based Signatures
• Hash-Based Multi-Signatures for Post-Quantum Ethereum
• Technical Note: LeanSig for Post-Quantum Ethereum
• Aborting Random Oracles: How to Build them, How to Use them
• The Billion Dollar Merkle Tree
• Poseidon: A New Hash Function for Zero-Knowledge Proof Systems
• Poseidon Cryptanalysis Initiative

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