inductive
definition
ReionizationEpoch
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IndisputableMonolith.Cosmology.ReionizationHistoryFromRS on GitHub at line 19.
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16namespace IndisputableMonolith.Cosmology.ReionizationHistoryFromRS
17open Constants
18
19inductive ReionizationEpoch where
20 | darkAges
21 | firstStars
22 | galaxyFormation
23 | bulkReionization
24 | saturation
25 deriving DecidableEq, Repr, BEq, Fintype
26
27theorem reionizationEpoch_count :
28 Fintype.card ReionizationEpoch = 5 := by decide
29
30noncomputable def boundaryRedshift (k : ℕ) : ℝ := phi ^ k
31
32theorem redshift_ratio (k : ℕ) :
33 boundaryRedshift (k + 1) / boundaryRedshift k = phi := by
34 unfold boundaryRedshift
35 have hpos : (0 : ℝ) < phi ^ k := pow_pos phi_pos k
36 rw [div_eq_iff hpos.ne', pow_succ]
37 ring
38
39theorem redshift_pos (k : ℕ) : 0 < boundaryRedshift k :=
40 pow_pos phi_pos k
41
42structure ReionizationCert where
43 five_epochs : Fintype.card ReionizationEpoch = 5
44 phi_ratio : ∀ k, boundaryRedshift (k + 1) / boundaryRedshift k = phi
45 boundary_always_pos : ∀ k, 0 < boundaryRedshift k
46
47noncomputable def reionizationCert : ReionizationCert where
48 five_epochs := reionizationEpoch_count
49 phi_ratio := redshift_ratio