Nuprl Lemma : discrete-pair-inv-property

∀[A:Type]. ∀[B:A ⟶ Type]. ∀[X:j⊢]. ∀[b:{X ⊢ _:discr(a:A × B[a])}].
  (discrete-pair(discrete-pair-inv(X;b)) = b ∈ {X ⊢ _:discr(a:A × B[a])})


Proof




Definitions occuring in Statement :  discrete-pair-inv: discrete-pair-inv(X;b),  discrete-pair: discrete-pair(p),  discrete-cubical-type: discr(T),  cubical-term: {X ⊢ _:A},  cubical_set: CubicalSet,  uall: ∀[x:A]. B[x],  so_apply: x[s],  function: x:A ⟶ B[x],  product: x:A × B[x],  universe: Type,  equal: s = t ∈ T
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  discrete-pair-inv: discrete-pair-inv(X;b),  so_apply: x[s],  uimplies: b supposing a,  discrete-pair: discrete-pair(p),  discrete-cubical-type: discr(T),  all: ∀x:A. B[x],  cubical-snd: p.2,  cubical-fst: p.1,  cubical-term-at: u(a),  cubical-pair: cubical-pair(u;v),  pi1: fst(t),  pi2: snd(t),  implies: P ⇒ Q
Lemmas referenced :  I_cube_wf,  fset_wf,  nat_wf,  cubical-term-equal,  discrete-cubical-type_wf,  cubical-term_wf,  cubical_set_wf,  istype-universe,  cubical_type_at_pair_lemma,  cubical-term-at_wf
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation_alt,  introduction,  cut,  equalitySymmetry,  functionExtensionality,  extract_by_obid,  sqequalHypSubstitution,  isectElimination,  thin,  hypothesisEquality,  hypothesis,  productEquality,  applyEquality,  equalityTransitivity,  independent_isectElimination,  universeIsType,  instantiate,  cumulativity,  sqequalRule,  isect_memberEquality_alt,  axiomEquality,  isectIsTypeImplies,  inhabitedIsType,  functionIsType,  universeEquality,  dependent_functionElimination,  Error :memTop,  lambdaFormation_alt,  productElimination,  dependent_pairEquality_alt,  equalityIstype,  independent_functionElimination

Latex:
\mforall{}[A:Type].  \mforall{}[B:A  {}\mrightarrow{}  Type].  \mforall{}[X:j\mvdash{}].  \mforall{}[b:\{X  \mvdash{}  \_:discr(a:A  \mtimes{}  B[a])\}].
    (discrete-pair(discrete-pair-inv(X;b))  =  b)



Date html generated: 2020_05_20-PM-03_40_58
Last ObjectModification: 2020_04_06-PM-07_12_28

Theory : cubical!type!theory


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