Lattice: A Post-Quantum Settlement Layer

TL;DR

Lattice is a post-quantum secure peer-to-peer digital cash system utilizing quantum-resistant cryptography, hardware, and network defenses, with a unique economic model and adaptive block parameters for long-term sustainability.

Contribution

It introduces a novel post-quantum settlement layer combining quantum-resistant signatures, adaptive difficulty, and hardware resilience, with detailed economic and network bootstrap mechanisms.

Findings

Successfully implements post-quantum cryptography in a blockchain context.

Employs LWMA-1 difficulty adjustment for network stability.

Features a halving schedule and tail emission for economic sustainability.

Abstract

We present Lattice (L, ticker: LAT), a peer-to-peer electronic cash system designed as a post-quantum settlement layer for the era of quantum computing. Lattice combines three independent defense vectors: hardware resilience through RandomX CPU-only proof-of-work, network resilience through LWMA-1 per-block difficulty adjustment (mitigating the Flash Hash Rate vulnerability that affects fixed-interval retarget protocols), and cryptographic resilience through ML-DSA-44 post-quantum digital signatures (NIST FIPS 204, lattice-based), enforced exclusively from the genesis block with no classical signature fallback. The protocol uses a brief warm-up period of 5,670 fast blocks (53-second target, 25 LAT reduced reward) for network bootstrap, then transitions permanently to 240-second blocks, following a 295,000-block halving schedule with a perpetual tail emission floor of 0.15 LAT per block. Block weight capacity grows in stages (11M to 28M to 56M) as the network matures. The smallest unit of LAT is the shor, named after Peter Shor, where 1 LAT = 10^8 shors.