Nuprl Lemma : universe-decode-encode
∀[X:j⊢]. ∀[T:{X ⊢ _}]. ∀[cT:X ⊢ CompOp(T)].  (decode(encode(T;cT)) = T ∈ {X ⊢ _})
Proof
Definitions occuring in Statement : 
universe-decode: decode(t), 
universe-encode: encode(T;cT), 
composition-op: Gamma ⊢ CompOp(A), 
cubical-type: {X ⊢ _}, 
cubical_set: CubicalSet, 
uall: ∀[x:A]. B[x], 
equal: s = t ∈ T
Definitions unfolded in proof : 
uall: ∀[x:A]. B[x], 
member: t ∈ T, 
uimplies: b supposing a, 
subtype_rel: A ⊆r B, 
cubical-type: {X ⊢ _}, 
universe-decode: decode(t), 
universe-encode: encode(T;cT), 
cubical-term-at: u(a), 
cubical-type-at: A(a), 
pi1: fst(t), 
csm-ap-type: (AF)s, 
context-map: <rho>, 
csm-ap: (s)x, 
functor-arrow: arrow(F), 
cube-set-restriction: f(s), 
universe-type: universe-type(t;I;a), 
I_cube: A(I), 
functor-ob: ob(F), 
formal-cube: formal-cube(I), 
names-hom: I ⟶ J, 
all: ∀x:A. B[x], 
squash: ↓T, 
prop: ℙ, 
true: True, 
guard: {T}, 
iff: P ⇐⇒ Q, 
and: P ∧ Q, 
rev_implies: P ⇐ Q, 
implies: P ⇒ Q
Lemmas referenced : 
cubical-type-equal2, 
universe-decode_wf, 
universe-encode_wf, 
composition-op_wf, 
cubical_set_cumulativity-i-j, 
cubical-type-cumulativity2, 
cubical-type_wf, 
cubical_set_wf, 
I_cube_wf, 
fset_wf, 
nat_wf, 
cube-set-restriction-id, 
cubical-type-at_wf, 
formal-cube_wf1, 
universe-type_wf, 
nh-id_wf, 
names-hom_wf, 
cubical_type_ap_morph_pair_lemma, 
subtype_rel-equal, 
cube-set-restriction_wf, 
equal_wf, 
squash_wf, 
true_wf, 
istype-universe, 
cube-set-restriction-comp, 
subtype_rel_self, 
iff_weakening_equal, 
nh-id-right
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
isect_memberFormation_alt, 
cut, 
introduction, 
extract_by_obid, 
sqequalHypSubstitution, 
isectElimination, 
thin, 
hypothesisEquality, 
hypothesis, 
independent_isectElimination, 
universeIsType, 
instantiate, 
applyEquality, 
sqequalRule, 
setElimination, 
rename, 
productElimination, 
dependent_pairEquality_alt, 
functionExtensionality, 
because_Cache, 
dependent_functionElimination, 
Error :memTop, 
lambdaEquality_alt, 
imageElimination, 
equalityTransitivity, 
equalitySymmetry, 
universeEquality, 
natural_numberEquality, 
imageMemberEquality, 
baseClosed, 
independent_functionElimination, 
inhabitedIsType, 
functionIsType
Latex:
\mforall{}[X:j\mvdash{}].  \mforall{}[T:\{X  \mvdash{}  \_\}].  \mforall{}[cT:X  \mvdash{}  CompOp(T)].    (decode(encode(T;cT))  =  T)
Date html generated:
2020_05_20-PM-07_17_17
Last ObjectModification:
2020_04_25-PM-09_42_03
Theory : cubical!type!theory
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