Nuprl Lemma : csm-universe-type
∀[X:j⊢]. ∀[t:{X ⊢ _:c𝕌}]. ∀[I:fset(ℕ)]. ∀[a:X(I)]. ∀[K:fset(ℕ)]. ∀[f:K ⟶ I].
  ((universe-type(t;I;a))<f> = universe-type(t;K;f(a)) ∈ {formal-cube(K) ⊢ _})
Proof
Definitions occuring in Statement : 
universe-type: universe-type(t;I;a)
, 
cubical-universe: c𝕌
, 
cubical-term: {X ⊢ _:A}
, 
csm-ap-type: (AF)s
, 
cubical-type: {X ⊢ _}
, 
context-map: <rho>
, 
formal-cube: formal-cube(I)
, 
cube-set-restriction: f(s)
, 
I_cube: A(I)
, 
cubical_set: CubicalSet
, 
names-hom: I ⟶ J
, 
fset: fset(T)
, 
nat: ℕ
, 
uall: ∀[x:A]. B[x]
, 
equal: s = t ∈ T
Definitions unfolded in proof : 
uall: ∀[x:A]. B[x]
, 
universe-type: universe-type(t;I;a)
, 
member: t ∈ T
, 
all: ∀x:A. B[x]
, 
implies: P 
⇒ Q
, 
cubical-universe: c𝕌
, 
pi1: fst(t)
, 
subtype_rel: A ⊆r B
, 
names-hom: I ⟶ J
, 
I_cube: A(I)
, 
functor-ob: ob(F)
, 
formal-cube: formal-cube(I)
, 
cubical-type-ap-morph: (u a f)
, 
pi2: snd(t)
, 
closed-type-to-type: closed-type-to-type(T)
, 
closed-cubical-universe: cc𝕌
, 
csm-fibrant-type: csm-fibrant-type(G;H;s;FT)
, 
csm-ap-type: (AF)s
Lemmas referenced : 
cubical-term-at-morph, 
cubical-universe_wf, 
cubical-universe-at, 
pi1_wf_top, 
cubical-type_wf, 
formal-cube_wf1, 
names-hom_wf, 
I_cube_wf, 
fset_wf, 
nat_wf, 
istype-cubical-universe-term, 
cubical_set_wf, 
cubical-term-at_wf, 
csm-ap-type_wf, 
context-map_wf, 
subtype_rel_self
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
isect_memberFormation_alt, 
cut, 
thin, 
instantiate, 
introduction, 
extract_by_obid, 
sqequalHypSubstitution, 
isectElimination, 
because_Cache, 
hypothesisEquality, 
hypothesis, 
sqequalRule, 
Error :memTop, 
applyLambdaEquality, 
productElimination, 
independent_pairEquality, 
universeIsType, 
dependent_functionElimination, 
equalityTransitivity, 
equalitySymmetry, 
inhabitedIsType, 
lambdaFormation_alt, 
equalityIstype, 
independent_functionElimination, 
applyEquality
Latex:
\mforall{}[X:j\mvdash{}].  \mforall{}[t:\{X  \mvdash{}  \_:c\mBbbU{}\}].  \mforall{}[I:fset(\mBbbN{})].  \mforall{}[a:X(I)].  \mforall{}[K:fset(\mBbbN{})].  \mforall{}[f:K  {}\mrightarrow{}  I].
    ((universe-type(t;I;a))<f>  =  universe-type(t;K;f(a)))
Date html generated:
2020_05_20-PM-07_11_59
Last ObjectModification:
2020_04_25-PM-09_24_55
Theory : cubical!type!theory
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