inductive
definition
SolarWindType
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IndisputableMonolith.Astrophysics.SolarWindFromPhiLadder on GitHub at line 23.
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20namespace IndisputableMonolith.Astrophysics.SolarWindFromPhiLadder
21open Constants
22
23inductive SolarWindType where
24 | quiet | slow | intermediate | fast | extreme
25 deriving DecidableEq, Repr, BEq, Fintype
26
27theorem solarWindTypeCount : Fintype.card SolarWindType = 5 := by decide
28
29/-- Adjacent solar wind speeds at phi-ladder rungs. -/
30noncomputable def solarWindSpeed (k : ℕ) : ℝ := phi ^ k
31
32theorem solarWindSpeedRatio (k : ℕ) :
33 solarWindSpeed (k + 1) / solarWindSpeed k = phi := by
34 unfold solarWindSpeed
35 have hpos := pow_pos phi_pos k
36 rw [pow_succ, div_eq_iff hpos.ne']
37 ring
38
39structure SolarWindCert where
40 five_types : Fintype.card SolarWindType = 5
41 phi_ratio : ∀ k, solarWindSpeed (k + 1) / solarWindSpeed k = phi
42
43noncomputable def solarWindCert : SolarWindCert where
44 five_types := solarWindTypeCount
45 phi_ratio := solarWindSpeedRatio
46
47end IndisputableMonolith.Astrophysics.SolarWindFromPhiLadder