Nuprl Lemma : contractible_comp_wf
∀[X:j⊢]. ∀[A:{X ⊢ _}]. ∀[cA:X +⊢ Compositon(A)].  (contractible_comp(X;A;cA) ∈ X ⊢ Compositon(Contractible(A)))
Proof
Definitions occuring in Statement : 
contractible_comp: contractible_comp(X;A;cA)
, 
composition-structure: Gamma ⊢ Compositon(A)
, 
contractible-type: Contractible(A)
, 
cubical-type: {X ⊢ _}
, 
cubical_set: CubicalSet
, 
uall: ∀[x:A]. B[x]
, 
member: t ∈ T
Definitions unfolded in proof : 
contractible-type: Contractible(A)
, 
uall: ∀[x:A]. B[x]
, 
member: t ∈ T
, 
contractible_comp: contractible_comp(X;A;cA)
, 
subtype_rel: A ⊆r B
Lemmas referenced : 
sigma_comp_wf2, 
cubical-pi_wf, 
cube-context-adjoin_wf, 
cubical-type-cumulativity2, 
cubical_set_cumulativity-i-j, 
csm-ap-type_wf, 
cc-fst_wf, 
path-type_wf, 
csm-ap-term_wf, 
cc-snd_wf, 
composition-structure-cumulativity, 
pi_comp_wf2, 
csm-comp-structure_wf, 
path_comp_wf, 
composition-structure_wf, 
cubical-type_wf, 
cubical_set_wf
Rules used in proof : 
sqequalSubstitution, 
sqequalRule, 
sqequalReflexivity, 
sqequalTransitivity, 
computationStep, 
isect_memberFormation_alt, 
introduction, 
cut, 
extract_by_obid, 
sqequalHypSubstitution, 
isectElimination, 
thin, 
hypothesisEquality, 
instantiate, 
applyEquality, 
because_Cache, 
hypothesis, 
equalityTransitivity, 
equalitySymmetry, 
axiomEquality, 
universeIsType, 
isect_memberEquality_alt, 
isectIsTypeImplies, 
inhabitedIsType
Latex:
\mforall{}[X:j\mvdash{}].  \mforall{}[A:\{X  \mvdash{}  \_\}].  \mforall{}[cA:X  +\mvdash{}  Compositon(A)].
    (contractible\_comp(X;A;cA)  \mmember{}  X  \mvdash{}  Compositon(Contractible(A)))
Date html generated:
2020_05_20-PM-05_14_03
Last ObjectModification:
2020_04_17-AM-00_16_02
Theory : cubical!type!theory
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