Nuprl Lemma : contr-witness_wf

∀[X:j⊢]. ∀[A:{X ⊢ _}]. ∀[c:{X ⊢ _:A}]. ∀[p:{X.A ⊢ _:(Path_(A)p (c)p q)}].
  (contr-witness(X;c;p) ∈ {X ⊢ _:Contractible(A)})


Proof




Definitions occuring in Statement :  contr-witness: contr-witness(X;c;p),  contractible-type: Contractible(A),  path-type: (Path_A a b),  cc-snd: q,  cc-fst: p,  cube-context-adjoin: X.A,  csm-ap-term: (t)s,  cubical-term: {X ⊢ _:A},  csm-ap-type: (AF)s,  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,  contr-witness: contr-witness(X;c;p),  contractible-type: Contractible(A),  subtype_rel: A ⊆r B,  squash: ↓T,  prop: ℙ,  true: True,  all: ∀x:A. B[x],  uimplies: b supposing a,  guard: {T},  iff: P ⇐⇒ Q,  and: P ∧ Q,  rev_implies: P ⇐ Q,  implies: P ⇒ Q,  cubical-type: {X ⊢ _},  cc-snd: q,  cc-fst: p,  csm-ap-type: (AF)s,  csm-id-adjoin: [u],  csm-comp: G o F,  csm-ap: (s)x,  csm-id: 1(X),  csm-adjoin: (s;u),  compose: f o g,  pi1: fst(t),  csm-ap-term: (t)s,  pi2: snd(t)
Lemmas referenced :  cubical-pair_wf,  cubical-pi_wf,  cube-context-adjoin_wf,  cubical_set_cumulativity-i-j,  cubical-type-cumulativity2,  csm-ap-type_wf,  cc-fst_wf,  path-type_wf,  csm-ap-term_wf,  cc-snd_wf,  cubical-term_wf,  cubical-type_wf,  cubical_set_wf,  squash_wf,  true_wf,  cubical-lambda_wf,  equal_wf,  istype-universe,  csm-cubical-pi,  csm-id-adjoin_wf,  subtype_rel_self,  iff_weakening_equal,  csm_id_adjoin_fst_type_lemma,  csm-ap-id-type,  csm-path-type,  csm-adjoin_wf,  csm-comp_wf,  subtype_rel-equal,  cube_set_map_wf,  csm-id_wf
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation_alt,  introduction,  cut,  extract_by_obid,  sqequalHypSubstitution,  isectElimination,  thin,  hypothesisEquality,  instantiate,  applyEquality,  hypothesis,  sqequalRule,  because_Cache,  axiomEquality,  equalityTransitivity,  equalitySymmetry,  universeIsType,  isect_memberEquality_alt,  isectIsTypeImplies,  inhabitedIsType,  lambdaEquality_alt,  imageElimination,  natural_numberEquality,  imageMemberEquality,  baseClosed,  hyp_replacement,  universeEquality,  dependent_functionElimination,  independent_isectElimination,  productElimination,  independent_functionElimination,  Error :memTop,  setElimination,  rename

Latex:
\mforall{}[X:j\mvdash{}].  \mforall{}[A:\{X  \mvdash{}  \_\}].  \mforall{}[c:\{X  \mvdash{}  \_:A\}].  \mforall{}[p:\{X.A  \mvdash{}  \_:(Path\_(A)p  (c)p  q)\}].
    (contr-witness(X;c;p)  \mmember{}  \{X  \mvdash{}  \_:Contractible(A)\})



Date html generated: 2020_05_20-PM-03_23_30
Last ObjectModification: 2020_04_07-PM-03_49_59

Theory : cubical!type!theory


Home Index