Module LWE ⇔ Ring LWE

Module LWE is equivalent to Ring LWE.

Statement

Migrated verbatim from LS15 - Worst-case to average-case reductions for module lattices:

Introduced Module LWE (MLWE), which generalizes Ring LWE by considering rank- modules over a polynomial ring . When this recovers Ring LWE; when this recovers plain LWE. The module structure interpolates between the two extremes, yielding a flexible parameter trade-off between efficiency and security assumptions. Kyber (ML-KEM) and Dilithium (ML-DSA), the NIST post-quantum standards, are based on Module LWE.

Notes

class: unstated: no citing page says which notion of reduction is meant. Recording a class the wiki does not state would add a claim.

Recorded during migration and not fixed — these are claims about the source text, not changes to it:

  • STRUCTURAL: no Abstract heading; unlabelled editorial paragraph.
  • SUSPECTED IMPRECISION (recorded, not fixed): ‘when k = n this recovers plain LWE’ is wrong as stated. Plain LWE is the degree-1 ring R = Z at rank n; over a degree-n ring, rank n gives a module of total dimension n^2, not plain LWE. The k=1 Ring LWE half is correct.
  • MAJOR OMISSION: the page’s own title promises worst-case to average-case reductions for module lattices, and the inventory already records that edge (Assumptions/learning-with-errors.md:129 [worst-case-module-lattice-problems module-lwe], sourced to LS15). This editorial summary omits the paper’s actual theorem entirely and describes only the definition and deployments.
  • The Kyber/Dilithium sub-edge is a deployment claim with NO citation and no reference page for either scheme — sources[] left empty rather than fabricated.
  • The two specialisation equivalences (rank-1 = RLWE, rank-n = LWE) are NOT in the existing 861-record inventory; they are the only genuinely new content on this page.
  • No inline citations.