The row-corank bound for a uniform binary matrix
Lax342547.CorankCounting · concepts/Lax342547/CorankCounting.lean · lax-342547
No public endorsements yet.
Loading review…
Sign in with ORCIDNatural Language Statement
Theorem
A matrix with row corank at least s admits s independent row relations. Count the relation matrix first, then require every column to lie in its kernel. This gives the sharper 2^(ms-sn) probability bound used for the bounded row lists in Lemma 5.5, written as a ratio of nonnegative powers.
Concept map
Evidence
Lean source view on GitHub
| 1 | import Lax342547.LowRankCounting |
| 2 | |
| 3 | /-! |
| 4 | --- |
| 5 | title: The row-corank bound for a uniform binary matrix |
| 6 | type: theorem |
| 7 | --- |
| 8 | A matrix with row corank at least s admits s independent row relations. |
| 9 | Count the relation matrix first, then require every column to lie in its |
| 10 | kernel. This gives the sharper 2^(ms-sn) probability bound used for the |
| 11 | bounded row lists in Lemma 5.5, written as a ratio of nonnegative powers. |
| 12 | -/ |
| 13 | |
| 14 | namespace Lax342547.CorankCounting |
| 15 | |
| 16 | axiom exists_row_relations {K I J : Type} [Field K] [Fintype I] [Fintype J] |
| 17 | (M : Matrix I J K) (s : ℕ) (hs : M.rank + s ≤ Fintype.card I) : |
| 18 | ∃ C : Matrix (Fin s) I K, Function.Surjective C.mulVec ∧ C * M = 0 |
| 19 | |
| 20 | open Lax342547.MomentSpace |
| 21 | open scoped ENNReal |
| 22 | |
| 23 | axiom card_corank {I J : Type} [Fintype I] [Fintype J] (s : ℕ) : |
| 24 | Nat.card {M : Matrix I J Binary // M.rank + s ≤ Fintype.card I} ≤ |
| 25 | 2 ^ (s * Fintype.card I + (Fintype.card I - s) * Fintype.card J) |
| 26 | |
| 27 | axiom uniform_corank_bound {I J : Type} [Fintype I] [Fintype J] [DecidableEq I] [DecidableEq J] |
| 28 | (s : ℕ) : |
| 29 | (PMF.uniformOfFintype (Matrix I J Binary)).toOuterMeasure {M | M.rank + s ≤ Fintype.card I} ≤ |
| 30 | (2 : ℝ≥0∞) ^ (s * Fintype.card I) / 2 ^ (s * Fintype.card J) |
| 31 | |
| 32 | end Lax342547.CorankCounting |
| 33 |
Discussion
Ask a question or add context. Endorsements and structured flags are kept in the review panel above.
0 comments