Nuprl Lemma : contraction-to-extend_wf
∀[Gamma:j⊢]. ∀[A:{Gamma ⊢ _}]. ∀[cA:Gamma ⊢ Compositon(A)]. ∀[ctr:{Gamma ⊢ _:Contractible(A)}].
  (contraction-to-extend(Gamma;A;cA;ctr) ∈ Gamma ⊢ Extension(A))
Proof
Definitions occuring in Statement : 
contraction-to-extend: contraction-to-extend(Gamma;A;cA;ctr), 
uniform-extend: uniform-extend{i:l}(Gamma; A), 
composition-structure: Gamma ⊢ Compositon(A), 
contractible-type: Contractible(A), 
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, 
contraction-to-extend: contraction-to-extend(Gamma;A;cA;ctr), 
extension-fun: extension-fun{i:l}(Gamma;A), 
subtype_rel: A ⊆r B, 
uimplies: b supposing a, 
all: ∀x:A. B[x], 
implies: P ⇒ Q, 
and: P ∧ Q, 
guard: {T}, 
csm-comp-structure: (cA)tau, 
interval-type: 𝕀, 
csm-comp: G o F, 
compose: f o g, 
cubical-type: {X ⊢ _}, 
csm-ap-type: (AF)s, 
csm-id: 1(X), 
csm-ap: (s)x, 
interval-0: 0(𝕀), 
csm-id-adjoin: [u], 
csm-adjoin: (s;u), 
constrained-cubical-term: {Gamma ⊢ _:A[phi |⟶ t]}, 
uniform-extend: uniform-extend{i:l}(Gamma; A), 
uniform-extension-fun: uniform-extension-fun{i:l}(Gamma;A;ext), 
prop: ℙ, 
cubical-path-app: pth @ r, 
cand: A c∧ B, 
composition-structure: Gamma ⊢ Compositon(A), 
squash: ↓T, 
true: True, 
cc-fst: p, 
csm+: tau+, 
interval-1: 1(𝕀), 
cc-snd: q, 
constant-cubical-type: (X), 
pi1: fst(t), 
contr-path: contr-path(c;x), 
path-eta: path-eta(pth), 
csm-ap-term: (t)s, 
pi2: snd(t)
Lemmas referenced : 
contr-center_wf, 
csm-ap-type_wf, 
csm-ap-term_wf, 
contractible-type_wf, 
subset-cubical-term2, 
sub_cubical_set_self, 
csm-contractible-type, 
contr-path_wf, 
context-subset_wf, 
thin-context-subset, 
contractible-type-subset, 
context-subset-is-subset, 
path-eta_wf, 
path-type-subtype, 
context-subset-term-subtype, 
csm-comp-structure_wf, 
cube-context-adjoin_wf, 
interval-type_wf, 
cc-fst_wf_interval, 
csm-comp_term, 
csm_id_adjoin_fst_type_lemma, 
subset-cubical-term, 
istype-cubical-term, 
cubical_set_cumulativity-i-j, 
cubical-type-cumulativity2, 
csm-context-subset-subtype2, 
face-type_wf, 
cube_set_map_wf, 
uniform-extension-fun_wf, 
composition-structure_wf, 
cubical-type_wf, 
cubical_set_wf, 
cubical-path-app-0, 
cubical-path-app-1, 
path-eta-0, 
path-eta-1, 
comp_term_wf, 
constrained-cubical-term_wf, 
squash_wf, 
true_wf, 
csm-id-adjoin-subset, 
equal_wf, 
istype-universe, 
cubical-term_wf, 
csm-path-eta, 
csm-cubical-app, 
csm-cubical-snd, 
csm-contr-center, 
csm-face-type, 
context-subset-map, 
subtype_rel_self
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
isect_memberFormation_alt, 
introduction, 
cut, 
lambdaEquality_alt, 
extract_by_obid, 
sqequalHypSubstitution, 
isectElimination, 
thin, 
because_Cache, 
hypothesisEquality, 
hypothesis, 
applyEquality, 
independent_isectElimination, 
sqequalRule, 
Error :memTop, 
lambdaFormation_alt, 
equalityTransitivity, 
equalitySymmetry, 
inhabitedIsType, 
independent_pairFormation, 
equalityIstype, 
dependent_functionElimination, 
independent_functionElimination, 
productElimination, 
instantiate, 
setElimination, 
rename, 
dependent_set_memberEquality_alt, 
universeIsType, 
axiomEquality, 
isect_memberEquality_alt, 
isectIsTypeImplies, 
applyLambdaEquality, 
imageMemberEquality, 
baseClosed, 
imageElimination, 
natural_numberEquality, 
hyp_replacement, 
universeEquality, 
functionEquality, 
cumulativity
Latex:
\mforall{}[Gamma:j\mvdash{}].  \mforall{}[A:\{Gamma  \mvdash{}  \_\}].  \mforall{}[cA:Gamma  \mvdash{}  Compositon(A)].  \mforall{}[ctr:\{Gamma  \mvdash{}  \_:Contractible(A)\}].
    (contraction-to-extend(Gamma;A;cA;ctr)  \mmember{}  Gamma  \mvdash{}  Extension(A))
Date html generated:
2020_05_20-PM-05_23_07
Last ObjectModification:
2020_04_17-PM-00_39_36
Theory : cubical!type!theory
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