Add pwedge_pequiv and plift_pwedge.

This commit is contained in:
favonia 2017-06-08 14:11:02 -06:00
parent 85c0ae53a6
commit 4165f9a613

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@ -2,7 +2,7 @@
import homotopy.wedge
open wedge pushout eq prod sum pointed equiv is_equiv unit
open wedge pushout eq prod sum pointed equiv is_equiv unit lift
namespace wedge
@ -38,4 +38,15 @@ namespace wedge
-- TODO: wedge is associative
definition pwedge_pequiv [constructor] {A A' B B' : Type*} (a : A ≃* A') (b : B ≃* B') : A B ≃* A' B' :=
begin
fapply pequiv_of_equiv,
exact pushout.equiv !pconst !pconst !pconst !pconst !pequiv.refl a b (λdummy, respect_pt a) (λdummy, respect_pt b),
exact ap pushout.inl (respect_pt a)
end
definition plift_pwedge.{u v} (A B : Type*) : plift.{u v} (A B) ≃* plift.{u v} A plift.{u v} B :=
calc plift.{u v} (A B) ≃* A B : by exact !pequiv_plift⁻¹ᵉ*
... ≃* plift.{u v} A plift.{u v} B : by exact pwedge_pequiv !pequiv_plift !pequiv_plift
end wedge