Nuprl Lemma : equiv-discrete-type

A,B:Type. ∀f:A ⟶ B.  (Bij(A;B;f)  (∀X:j⊢{X ⊢ _:Equiv(discr(A);discr(B))}))


Proof




Definitions occuring in Statement :  cubical-equiv: Equiv(T;A) discrete-cubical-type: discr(T) cubical-term: {X ⊢ _:A} cubical_set: CubicalSet biject: Bij(A;B;f) all: x:A. B[x] implies:  Q function: x:A ⟶ B[x] universe: Type
Definitions unfolded in proof :  all: x:A. B[x] implies:  Q uall: [x:A]. B[x] member: t ∈ T exists: x:A. B[x] and: P ∧ Q uimplies: supposing a subtype_rel: A ⊆B prop:
Lemmas referenced :  biject-inverse bijection-equiv_wf cubical_set_cumulativity-i-j cubical_set_wf biject_wf istype-universe
Rules used in proof :  sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity lambdaFormation_alt cut introduction extract_by_obid sqequalHypSubstitution isectElimination thin hypothesisEquality independent_functionElimination hypothesis productElimination instantiate cumulativity independent_isectElimination applyEquality sqequalRule universeIsType functionIsType inhabitedIsType universeEquality

Latex:
\mforall{}A,B:Type.  \mforall{}f:A  {}\mrightarrow{}  B.    (Bij(A;B;f)  {}\mRightarrow{}  (\mforall{}X:j\mvdash{}.  \{X  \mvdash{}  \_:Equiv(discr(A);discr(B))\}))



Date html generated: 2020_05_20-PM-03_43_05
Last ObjectModification: 2020_04_06-PM-07_14_26

Theory : cubical!type!theory


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