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Brennan's Conjecture

Reference:

namespace BrennanConjectureopen Complex Filter MeasureTheory Set Topologydef unitDisk : Set := {z | z < 1}

The standard class $\mathcal{S}$ of normalised univalent functions on $\mathbb{D}$.

structure IsUnivalentNormalized (f : ) : Prop where analyticOn : AnalyticOn f unitDisk injOn : InjOn f unitDisk map_zero : f 0 = 0 deriv_zero : deriv f 0 = 1

$\beta_f(\tau) := \limsup_{r \to 1^-} \frac{\log \int_{-\pi}^{\pi} |f'(re^{i\theta})|^\tau , d\theta}{|\log(1-r)|}$

noncomputable def integralMeansSpectrum (f : ) (τ : ) : := limsup (fun r => Real.log ( θ in Ioc (-Real.pi) Real.pi, deriv f (r exp (Complex.I * θ)) ^ τ) / |Real.log (1 - r)|) (𝓝[Iio 1] (1 : ))noncomputable def universalSpectrum (τ : ) : := sSup {β | f : , IsUnivalentNormalized f β = integralMeansSpectrum f τ}noncomputable def universalSpectrumBounded (τ : ) : := sSup {β | f : , IsUnivalentNormalized f Bornology.IsBounded (f '' unitDisk) β = integralMeansSpectrum f τ}@[category API, AMS 30] theorem universalSpectrumBounded_le (τ : ) : universalSpectrumBounded τ universalSpectrum τ := τ:universalSpectrumBounded τ universalSpectrum τ τ:BddAbove {β | f, IsUnivalentNormalized f β = integralMeansSpectrum f τ}τ:{β | f, IsUnivalentNormalized f Bornology.IsBounded (f '' unitDisk) β = integralMeansSpectrum f τ}.Nonemptyτ:{β | f, IsUnivalentNormalized f Bornology.IsBounded (f '' unitDisk) β = integralMeansSpectrum f τ} {β | f, IsUnivalentNormalized f β = integralMeansSpectrum f τ} τ:BddAbove {β | f, IsUnivalentNormalized f β = integralMeansSpectrum f τ} All goals completed! 🐙 τ:{β | f, IsUnivalentNormalized f Bornology.IsBounded (f '' unitDisk) β = integralMeansSpectrum f τ}.Nonempty All goals completed! 🐙 τ:{β | f, IsUnivalentNormalized f Bornology.IsBounded (f '' unitDisk) β = integralMeansSpectrum f τ} {β | f, IsUnivalentNormalized f β = integralMeansSpectrum f τ} τ:f: hf:IsUnivalentNormalized fleft✝:Bornology.IsBounded (f '' unitDisk)integralMeansSpectrum f τ {β | f, IsUnivalentNormalized f β = integralMeansSpectrum f τ}; All goals completed! 🐙@[category test, AMS 30] theorem integralMeansSpectrum_id (τ : ) : integralMeansSpectrum id τ = 0 := τ:integralMeansSpectrum id τ = 0 All goals completed! 🐙

Brennan's conjecture, part 1: $B(-2) = 1$.

@[category research open, AMS 30] theorem brennan_universalSpectrum : universalSpectrum (-2) = 1 := universalSpectrum (-2) = 1 All goals completed! 🐙

Brennan's conjecture, part 2: $B_b(-2) = 1$.

@[category research open, AMS 30] theorem brennan_universalSpectrumBounded : universalSpectrumBounded (-2) = 1 := universalSpectrumBounded (-2) = 1 All goals completed! 🐙

Brennan's conjecture, part 3: $B(-2) = B_b(-2)$.

All goals completed! 🐙

Brennan's conjecture: $B(-2) = B_b(-2) = 1$.

@[category API, AMS 30] theorem brennan : universalSpectrum (-2) = 1 universalSpectrumBounded (-2) = 1 := brennan_universalSpectrum, brennan_universalSpectrumBoundedend BrennanConjecture