Irreducibility survives the affine primitive-part reduction #
theorem
NairTenenbaum.affineRestriction_irreducible_map
{Q : Polynomial ℤ}
(hQ : Irreducible (Polynomial.map (Int.castRingHom ℚ) Q))
{M : ℤ}
(hM : M ≠ 0)
(a : ℤ)
:
Irreducible (Polynomial.map (Int.castRingHom ℚ) (affineRestriction Q M a))
theorem
NairTenenbaum.affineRestriction_primPart_irreducible_map
{Q : Polynomial ℤ}
(hQ : Irreducible (Polynomial.map (Int.castRingHom ℚ) Q))
{M : ℤ}
(hM : M ≠ 0)
(a : ℤ)
:
Irreducible (Polynomial.map (Int.castRingHom ℚ) (affineRestriction Q M a).primPart)
theorem
NairTenenbaum.exists_affine_primitive_reduction
{Q : Polynomial ℤ}
(hQ : Irreducible (Polynomial.map (Int.castRingHom ℚ) Q))
:
∃ (M : ℕ),
0 < M ∧ ∀ (a : ℤ),
NoFixedPrimeDivisor (affineRestriction Q (↑M) a).primPart ∧ Irreducible (Polynomial.map (Int.castRingHom ℚ) (affineRestriction Q (↑M) a).primPart)