Nuprl Lemma : uniform-extend-contractible

Gamma:j⊢. ∀A:{Gamma ⊢ _}. ∀ext:Gamma +⊢ Extension(A).  {Gamma ⊢ _:Contractible(A)}


Proof




Definitions occuring in Statement :  uniform-extend: uniform-extend{i:l}(Gamma; A) contractible-type: Contractible(A) cubical-term: {X ⊢ _:A} cubical-type: {X ⊢ _} cubical_set: CubicalSet all: x:A. B[x]
Definitions unfolded in proof :  all: x:A. B[x] member: t ∈ T subtype_rel: A ⊆B uall: [x:A]. B[x]
Lemmas referenced :  extend-to-contraction_wf cubical-type-cumulativity2 cubical_set_cumulativity-i-j uniform-extend_wf cubical-type_wf cubical_set_wf
Rules used in proof :  sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity lambdaFormation_alt introduction cut thin instantiate extract_by_obid sqequalHypSubstitution dependent_functionElimination hypothesisEquality applyEquality because_Cache hypothesis sqequalRule isectElimination universeIsType

Latex:
\mforall{}Gamma:j\mvdash{}.  \mforall{}A:\{Gamma  \mvdash{}  \_\}.  \mforall{}ext:Gamma  +\mvdash{}  Extension(A).    \{Gamma  \mvdash{}  \_:Contractible(A)\}



Date html generated: 2020_05_20-PM-05_23_21
Last ObjectModification: 2020_04_20-AM-10_13_40

Theory : cubical!type!theory


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