English
There exists weights w such that Q is equivalent to the weighted sum-of-squares representation; a standard diagonalization result.
Русский
Существуют веса w, делающие Q эквивалентной диагонализированной форме весов.
LaTeX
$$$\exists w, Q \text{ Equivalent } \operatorname{weightedSumSquares} K w$$$
Lean4
/-- `LinearMap.fst` as an isometry, when the second space has the zero quadratic form. -/
@[simps!]
def fst (Q₁ : QuadraticMap R M₁ P) : (Q₁.prod (0 : QuadraticMap R M₂ P)) →qᵢ Q₁
where
toLinearMap := LinearMap.fst R _ _
map_app' m₁ := by simp