Nuprl Lemma : contractible-type-at

[X,A,I,rho:Top].  (Contractible(A)(rho) u:A(rho) × cubical-pi-family(X.A;(A)p;(Path_((A)p)p (q)p q);I;(rho;u)))


Proof




Definitions occuring in Statement :  contractible-type: Contractible(A) path-type: (Path_A b) cubical-pi-family: cubical-pi-family(X;A;B;I;a) cc-snd: q cc-fst: p cc-adjoin-cube: (v;u) cube-context-adjoin: X.A csm-ap-term: (t)s csm-ap-type: (AF)s cubical-type-at: A(a) uall: [x:A]. B[x] top: Top product: x:A × B[x] sqequal: t
Definitions unfolded in proof :  uall: [x:A]. B[x] member: t ∈ T contractible-type: Contractible(A) cubical-pi: ΠB cubical-sigma: Σ B all: x:A. B[x] top: Top
Lemmas referenced :  cubical_type_at_pair_lemma top_wf
Rules used in proof :  sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity isect_memberFormation introduction cut sqequalRule extract_by_obid sqequalHypSubstitution dependent_functionElimination thin isect_memberEquality voidElimination voidEquality hypothesis sqequalAxiom isectElimination hypothesisEquality because_Cache

Latex:
\mforall{}[X,A,I,rho:Top].
    (Contractible(A)(rho)  \msim{}  u:A(rho)  \mtimes{}  cubical-pi-family(X.A;(A)p;(Path\_((A)p)p  (q)p  q);I;(rho;u)))



Date html generated: 2018_05_23-AM-09_39_12
Last ObjectModification: 2018_05_20-PM-06_39_41

Theory : cubical!type!theory


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