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Add lean source and binary files (part 19)
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import OAI.Analysis.HyperbolicCones.Pencil
import OAI.Analysis.HyperbolicCones.TangentObstruction
import OAI.Analysis.HyperbolicCones.Deformation
import OAI.Analysis.HyperbolicCones.LinePolynomial
import OAI.Analysis.HyperbolicCones.ConeZero
import OAI.Analysis.HyperbolicCones.Coordinates
namespace OAI
noncomputable section
open Matrix
open scoped Matrix.Norms.L2Operator
namespace Paper256
theorem cone_not_spectrahedral (N : ℕ) (hN : 0 < N) (L : Ambient →ₗ[ℝ] Sym N) :
cone ≠ {x | (L x : Mat N ℝ).PosSemidef} := by
intro hL
obtain ⟨P⟩ := pencil_normalization N hN L hL
exact P.impossible
/-- An explicit degree-20 hyperbolic polynomial in a 23-dimensional real space
whose closed hyperbolicity cone is not spectrahedral. -/
theorem main_result :
Module.finrank ℝ Ambient = 23 ∧
polynomial.IsHomogeneous 20 ∧
polynomial.totalDegree = 20 ∧
MvPolynomial.eval (coordinates basePoint) polynomial = 1 ∧
(∀ (x : Ambient) (z : ℂ), (linePolynomial x).aeval z = 0 → z.im = 0) ∧
∀ (N : ℕ) (_hN : 0 < N) (L : Ambient →ₗ[ℝ] Sym N),
cone ≠ {x | (L x : Mat N ℝ).PosSemidef} := by
exact ⟨ambient_finrank, polynomial_homogeneous, polynomial_totalDegree,
polynomial_basePoint, linePolynomial_complex_roots_real, cone_not_spectrahedral⟩
end Paper256
end
end OAI