Nuprl Lemma : equiv-witness_wf

[G:j⊢]. ∀[A,T:{G ⊢ _}]. ∀[f:{G ⊢ _:(T ⟶ A)}]. ∀[iseq:{G ⊢ _:IsEquiv(T;A;f)}].
  (equiv-witness(f;iseq) ∈ {G ⊢ _:Equiv(T;A)})


Proof




Definitions occuring in Statement :  equiv-witness: equiv-witness(f;cntr) cubical-equiv: Equiv(T;A) is-cubical-equiv: IsEquiv(T;A;w) cubical-fun: (A ⟶ B) cubical-term: {X ⊢ _:A} cubical-type: {X ⊢ _} cubical_set: CubicalSet uall: [x:A]. B[x] member: t ∈ T
Definitions unfolded in proof :  uall: [x:A]. B[x] member: t ∈ T equiv-witness: equiv-witness(f;cntr) cubical-equiv: Equiv(T;A) subtype_rel: A ⊆B all: x:A. B[x] squash: T prop: true: True uimplies: supposing a guard: {T} iff: ⇐⇒ Q and: P ∧ Q rev_implies:  Q implies:  Q
Lemmas referenced :  cubical-term_wf is-cubical-equiv_wf cubical-type-cumulativity2 cubical_set_cumulativity-i-j cubical-fun_wf cubical-type_wf cubical_set_wf cubical-pair_wf cube-context-adjoin_wf csm-ap-type_wf cc-fst_wf cc-snd_wf-cubical-fun squash_wf true_wf equal_wf istype-universe csm-is-cubical-equiv csm-id-adjoin_wf subtype_rel_self iff_weakening_equal csm_id_adjoin_fst_type_lemma csm-ap-id-type cc_snd_csm_id_adjoin_lemma csm-ap-id-term
Rules used in proof :  sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity isect_memberFormation_alt introduction cut sqequalHypSubstitution hypothesis sqequalRule axiomEquality equalityTransitivity equalitySymmetry universeIsType thin instantiate extract_by_obid isectElimination hypothesisEquality applyEquality isect_memberEquality_alt isectIsTypeImplies inhabitedIsType because_Cache dependent_functionElimination lambdaEquality_alt hyp_replacement imageElimination natural_numberEquality imageMemberEquality baseClosed universeEquality independent_isectElimination productElimination independent_functionElimination Error :memTop

Latex:
\mforall{}[G:j\mvdash{}].  \mforall{}[A,T:\{G  \mvdash{}  \_\}].  \mforall{}[f:\{G  \mvdash{}  \_:(T  {}\mrightarrow{}  A)\}].  \mforall{}[iseq:\{G  \mvdash{}  \_:IsEquiv(T;A;f)\}].
    (equiv-witness(f;iseq)  \mmember{}  \{G  \mvdash{}  \_:Equiv(T;A)\})



Date html generated: 2020_05_20-PM-03_27_22
Last ObjectModification: 2020_04_06-PM-06_45_51

Theory : cubical!type!theory


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