Nuprl Lemma : sigma-comp-exists

∀Gamma:j⊢. ∀A:{Gamma ⊢ _}. ∀B:{Gamma.A ⊢ _}.  (Gamma ⊢ CompOp(A) ⇒ Gamma.A ⊢ CompOp(B) ⇒ Gamma ⊢ CompOp(Σ A B))


Proof




Definitions occuring in Statement :  composition-op: Gamma ⊢ CompOp(A),  cubical-sigma: Σ A B,  cube-context-adjoin: X.A,  cubical-type: {X ⊢ _},  cubical_set: CubicalSet,  all: ∀x:A. B[x],  implies: P ⇒ Q
Definitions unfolded in proof :  all: ∀x:A. B[x],  implies: P ⇒ Q,  member: t ∈ T,  uall: ∀[x:A]. B[x],  subtype_rel: A ⊆r B
Lemmas referenced :  sigmacomp_wf,  cubical-type-cumulativity2,  cubical_set_cumulativity-i-j,  cube-context-adjoin_wf,  composition-op_wf,  cubical-type_wf,  cubical_set_wf
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  lambdaFormation_alt,  rename,  introduction,  cut,  thin,  instantiate,  extract_by_obid,  sqequalHypSubstitution,  isectElimination,  hypothesisEquality,  applyEquality,  because_Cache,  hypothesis,  sqequalRule,  universeIsType

Latex:
\mforall{}Gamma:j\mvdash{}.  \mforall{}A:\{Gamma  \mvdash{}  \_\}.  \mforall{}B:\{Gamma.A  \mvdash{}  \_\}.
    (Gamma  \mvdash{}  CompOp(A)  {}\mRightarrow{}  Gamma.A  \mvdash{}  CompOp(B)  {}\mRightarrow{}  Gamma  \mvdash{}  CompOp(\mSigma{}  A  B))



Date html generated: 2020_05_20-PM-04_06_32
Last ObjectModification: 2020_04_10-AM-03_42_27

Theory : cubical!type!theory


Home Index