OAI/MeasureTheory/Falconer/Measures/MonotoneMeasureMass.lean
2 declarations, 0 contain sorry, 0 declared as axioms
Positive increments of decreasing finite measures
This is the measure-theoretic telescoping step of asm:monotone-shell.
The total variation of each positive decrement is its mass, and those
masses are summable. No quantitative convergence rate is introduced.
- theorem
OAI.Falconer.antitone_measure_sum_decrementsline 24Source documentation
The finite telescoping identity is an equality of measures, not just of masses. Each difference is the positive measure difference.
theorem antitone_measure_sum_decrements (α : ℕ → Measure X) [∀ n, IsFiniteMeasure (α n)] (hα : Antitone α) (N : ℕ) : (∑ n ∈ Finset.range N, (α n - α (n + 1))) + α N = α 0 := by … - theorem
OAI.Falconer.summable_antitone_measure_decrementsline 36Source documentation
Monotonicity and finite initial mass supply precisely the summability needed for the variation correction in the shell argument.
theorem summable_antitone_measure_decrements (α : ℕ → Measure X) [∀ n, IsFiniteMeasure (α n)] (hα : Antitone α) : Summable (fun n => (α n - α (n + 1)).real univ) := by …