Scalar Pitchfork Lean 4 library · release v0.1.0
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Modules

The library root imports every module below.

Module Contents
ScalarPitchfork.Cubic The exact cubic $\alpha\tau A-\beta A^3$: nonzero zeros $\pm\sqrt{\alpha\tau/\beta}$ on the side $\tau\beta>0$, derivative $-2\alpha\tau$ there
ScalarPitchfork.Perturbed At a given nonzero zero of a perturbed cubic: side, derivative sign, square-root amplitude error
ScalarPitchfork.Existence The field pitchforkField; both signed branches exist under the remainder bounds (intermediate value theorem), side and stability of every small zero
ScalarPitchfork.Branch Uniqueness in a fixed window, classification of small zeros, continuity of the branch functions; packaged in pitchfork_branch_curves
ScalarPitchfork.StrongRemainder The stronger remainder bound implies the weak one; the branch theorems transfer
ScalarPitchfork.Jet PitchforkJet: $C^4$, the axis condition and five vanishing jets give the remainder bounds; the stronger bound holds iff $\partial_zR(\tau,0)=0$; branch theorems from jets
ScalarPitchfork.JetCounterexample $R=\tau^2z$: the jets do not give the stronger bound; the axis condition from an exact linearization
ScalarPitchfork.Global.Alternatives The three global alternatives as hypotheses: elimination, closedness, unbounded parameter, connectedness propagation, exclusion for strictly monotone profiles
ScalarPitchfork.Global.ComponentClosure Parent component, one-sided remainder and selected component of a solution set; closedness