Module

NormalSplittingPolynomial.lean

Nyll.ValuedFieldTheory.Valuation.NormalSplittingPolynomial
1 declaration indexed from sourceView source ↗

Nonzero splitting polynomials for finite normal extensions

A finite normal extension is the splitting field of a nonzero polynomial. If the polynomial supplied by the standard existence theorem is zero, the constant polynomial one has the same empty root set and generates the same extension.

Declarations

Normal.exists_ne_zero_isSplittingField

A finite normal extension admits a nonzero splitting polynomial.

Source context 1 command

Surrounding namespaces, section variables, and local commands at this declaration.

namespace Normal
theorem exists_ne_zero_isSplittingField
    (F K : Type*) [Field F] [Field K] [Algebra F K]
    [Normal F K] [FiniteDimensional F K] :
    ∃ f : Polynomial F, f ≠ 0 ∧ Polynomial.IsSplittingField F K f