OAI/LinearAlgebra/MatrixMultiplication/AuxiliarySeparation/Arithmetic/ExponentComparison.lean
3 declarations, 0 contain sorry, 0 declared as axioms
Comparing power growth
The last scalar step of the auxiliary-separation argument compares a fourth-power lower bound for the cube of the diagonal profile with its dimension upper bound. Powers of two suffice to compare the exponents, so the argument needs no asymptotic estimates or approximation of constants.
- theorem
OAI.MatrixMultiplication.AuxiliarySeparation.rpow_exponent_le_of_nat_boundline 19Source documentation
A uniform bound on all positive natural inputs forces the exponent on the left to be no larger than the exponent on the right.
theorem rpow_exponent_le_of_nat_bound {a b C : ℝ} (hbound : ∀ n : ℕ, 1 ≤ n → (n : ℝ) ^ a ≤ C * (n : ℝ) ^ b) : a ≤ b := by … - theorem
OAI.MatrixMultiplication.AuxiliarySeparation.diagonal_exponent_le_three_quartersline 43Source documentation
The diagonal lower bound and the dimension upper bound force the scalar exponent to be at most
3/4.theorem diagonal_exponent_le_three_quarters {D : ℕ → ℝ} {t : ℝ} (ht : 0 < t) (hnonneg : ∀ n : ℕ, 1 ≤ n → 0 ≤ D n) (hlower : ∀ n : ℕ, 1 ≤ n → (n : ℝ) ^ 4 ≤ D n ^ 3) (hupper : ∀ n : ℕ, 1 ≤ n → D n ≤ (2 * (n : ℝ) - 1) ^ (1 / t)) : t ≤ 3 / 4 := by … - theorem
OAI.MatrixMultiplication.AuxiliarySeparation.three_mul_diagonal_exponent_le_nine_quartersline 78Source documentation
The scalar comparison in the normalization used for the matrix multiplication exponent.
theorem three_mul_diagonal_exponent_le_nine_quarters {D : ℕ → ℝ} {t : ℝ} (ht : 0 < t) (hnonneg : ∀ n : ℕ, 1 ≤ n → 0 ≤ D n) (hlower : ∀ n : ℕ, 1 ≤ n → (n : ℝ) ^ 4 ≤ D n ^ 3) (hupper : ∀ n : ℕ, 1 ≤ n → D n ≤ (2 * (n : ℝ) - 1) ^ (1 / t)) : 3 * t ≤ 9 / 4 := by …