Nuprl Lemma : extend-to-contraction_wf

∀Gamma:j⊢. ∀A:{Gamma ⊢ _}. ∀ext:Gamma +⊢ Extension(A).
  (extend-to-contraction(Gamma;A;ext) ∈ {Gamma ⊢ _:Contractible(A)})


Proof




Definitions occuring in Statement :  extend-to-contraction: extend-to-contraction(Gamma;A;ext),  uniform-extend: uniform-extend{i:l}(Gamma; A),  contractible-type: Contractible(A),  cubical-term: {X ⊢ _:A},  cubical-type: {X ⊢ _},  cubical_set: CubicalSet,  all: ∀x:A. B[x],  member: t ∈ T
Definitions unfolded in proof :  all: ∀x:A. B[x],  member: t ∈ T,  uniform-extend: uniform-extend{i:l}(Gamma; A),  extension-fun: extension-fun{i:l}(Gamma;A),  uall: ∀[x:A]. B[x],  subtype_rel: A ⊆r B,  extend-to-contraction: extend-to-contraction(Gamma;A;ext),  constrained-cubical-term: {Gamma ⊢ _:A[phi |⟶ t]},  uimplies: b supposing a,  so_lambda: λ2x.t[x],  so_apply: x[s],  cubical-type: {X ⊢ _},  cc-snd: q,  interval-type: 𝕀,  cc-fst: p,  csm-ap-type: (AF)s,  constant-cubical-type: (X),  csm-comp: G o F,  compose: f o g,  csm-ap: (s)x,  squash: ↓T,  prop: ℙ,  true: True,  uniform-extension-fun: uniform-extension-fun{i:l}(Gamma;A;ext),  pi1: fst(t),  csm-adjoin: (s;u),  csm-id: 1(X),  csm-id-adjoin: [u],  interval-0: 0(𝕀),  implies: P ⇒ Q,  interval-1: 1(𝕀),  csm-ap-term: (t)s,  pi2: snd(t),  guard: {T},  iff: P ⇐⇒ Q,  and: P ∧ Q,  rev_implies: P ⇐ Q
Lemmas referenced :  csm-ap-term_wf,  cube-context-adjoin_wf,  cubical-type-cumulativity2,  cubical_set_cumulativity-i-j,  interval-type_wf,  csm-ap-type_wf,  cc-fst_wf,  cc-fst_wf_interval,  cc-snd_wf,  contr-witness_wf,  csm-id_wf,  face-0_wf,  empty-context-subset-lemma3,  subtype_rel_set,  cubical-term-eqcd,  equal-wf-base-T,  thin-context-subset,  context-subset_wf,  istype-cubical-term,  subset-cubical-term2,  sub_cubical_set_self,  csm-ap-id-type,  term-to-path_wf,  csm-comp_wf,  face-one_wf,  context-subset-is-subset,  context-subset-term-subtype,  path-type_wf,  squash_wf,  true_wf,  uniform-extend_wf,  cubical-type_wf,  cubical_set_wf,  csm-id-adjoin_wf-interval-0,  istype-universe,  equal_wf,  csm-face-0,  face-one-interval-0,  csm-interval-0,  cc_snd_csm_id_adjoin_lemma,  csm-face-one,  csm_id_adjoin_fst_term_lemma,  context-subset-map,  csm-id-adjoin_wf-interval-1,  interval-1_wf,  subset-cubical-term,  context-1-subset,  face-one-interval-1,  sub_cubical_set_wf,  face-type_wf,  iff_weakening_equal
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  lambdaFormation_alt,  cut,  sqequalHypSubstitution,  setElimination,  thin,  rename,  instantiate,  introduction,  extract_by_obid,  isectElimination,  hypothesisEquality,  applyEquality,  because_Cache,  hypothesis,  sqequalRule,  Error :memTop,  equalityTransitivity,  equalitySymmetry,  independent_isectElimination,  lambdaEquality_alt,  baseClosed,  dependent_functionElimination,  productElimination,  imageElimination,  universeIsType,  inhabitedIsType,  natural_numberEquality,  imageMemberEquality,  hyp_replacement,  universeEquality,  applyLambdaEquality,  equalityIstype,  independent_functionElimination

Latex:
\mforall{}Gamma:j\mvdash{}.  \mforall{}A:\{Gamma  \mvdash{}  \_\}.  \mforall{}ext:Gamma  +\mvdash{}  Extension(A).
    (extend-to-contraction(Gamma;A;ext)  \mmember{}  \{Gamma  \mvdash{}  \_:Contractible(A)\})



Date html generated: 2020_05_20-PM-05_22_45
Last ObjectModification: 2020_05_02-PM-03_25_05

Theory : cubical!type!theory


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