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: uall: [x:A]. B[x] equal: 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:  Q cubical-universe: c𝕌 pi1: fst(t) subtype_rel: A ⊆B names-hom: I ⟶ J I_cube: A(I) functor-ob: ob(F) formal-cube: formal-cube(I) cubical-type-ap-morph: (u 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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