WRSWorld Research StateContribute
WORLD RESEARCH STATE

Dilworth: finite-width chain decomposition of partially ordered sets

Contribution grade

Order theory and combinatorics · Exact theorem and reusable mathematical method

Reference score245,000Provisional editorial estimate of this exact contribution; its grade is assessed separately.

What changed

A partially ordered set of finite width k—no antichain of size k+1 and an antichain of size k—can be partitioned into k disjoint chains, and fewer chains cannot suffice. Dilworth proves the finite case and extends it to arbitrary finite-width ordered sets using a maximal principle. The paper applies the decomposition to set representatives and finite distributive-lattice embeddings.

Scientific scope

A partially ordered set of finite width k—no antichain of size k+1 and an antichain of size k—can be partitioned into k disjoint chains, and fewer chains cannot suffice. Dilworth proves the finite case and extends it to arbitrary finite-width ordered sets using a maximal principle. The paper applies the decomposition to set representatives and finite distributive-lattice embeddings. The infinite-set extension retains a finite integer width and uses the maximal principle; it is not an unrestricted infinite-cardinal chain-cover theorem or a constructive algorithm. The number of chains in a partition is not generally the Dushnik–Miller order dimension; the original distinguishes these representations. Hall/Rado and Kreweras representative theorems are inherited antecedents or consequences, not separately relabelled discoveries. The finite lattice application concerns lattice embeddings into a product of chains, not every non-distributive lattice.

Evidence

The linked original works support the scoped statement and contribution attribution. WRS has not independently replayed experiments or reconstructed a full mathematical proof. The infinite-set extension retains a finite integer width and uses the maximal principle; it is not an unrestricted infinite-cardinal chain-cover theorem or a constructive algorithm. The number of chains in a partition is not generally the Dushnik–Miller order dimension; the original distinguishes these representations. Hall/Rado and Kreweras representative theorems are inherited antecedents or consequences, not separately relabelled discoveries. The finite lattice application concerns lattice embeddings into a product of chains, not every non-distributive lattice.

Contributors

Provisional WRS assessment, edition 2026-10-23.3. Independent expert calibration is pending. This grade does not certify correctness or assign ownership.

Full scientific record · Browse contribution grades · Request a correction