Nuprl Lemma : sigma-path-fst

X:j⊢. ∀A:{X ⊢ _}. ∀B:{X.A ⊢ _}. ∀x,y:{X ⊢ _:Σ B}.  ({X ⊢ _:(Path_Σ y)}  {X ⊢ _:(Path_A x.1 y.1)})


Proof




Definitions occuring in Statement :  path-type: (Path_A b) cubical-fst: p.1 cubical-sigma: Σ B cube-context-adjoin: X.A cubical-term: {X ⊢ _:A} cubical-type: {X ⊢ _} cubical_set: CubicalSet all: x:A. B[x] implies:  Q
Definitions unfolded in proof :  all: x:A. B[x] implies:  Q member: t ∈ T uall: [x:A]. B[x] subtype_rel: A ⊆B and: P ∧ Q cubical-type: {X ⊢ _} cc-snd: q cc-fst: p csm-ap-type: (AF)s interval-type: 𝕀 csm-comp: F csm-ap: (s)x constant-cubical-type: (X) compose: g uimplies: supposing a cubical-path-app: pth r true: True same-cubical-term: X ⊢ u=v:A squash: T prop: guard: {T} iff: ⇐⇒ Q rev_implies:  Q
Lemmas referenced :  cubical-term_wf path-type_wf cubical-sigma_wf cubical-type-cumulativity2 cubical_set_cumulativity-i-j cube-context-adjoin_wf cubical-type_wf cubical_set_wf path-eta_wf path-type-subtype cubical-sigma-p interval-type_wf term-to-path-wf cubical-fst_wf csm-ap-type_wf cc-fst_wf csm-adjoin_wf csm-comp_wf cc-snd_wf csm-cubical-fst path-eta-1 path-eta-0 same-cubical-term_wf squash_wf true_wf cubical-path-app-1 iff_weakening_equal cubical-path-app-0
Rules used in proof :  sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity lambdaFormation_alt universeIsType cut thin instantiate introduction extract_by_obid sqequalHypSubstitution isectElimination hypothesisEquality applyEquality hypothesis sqequalRule inhabitedIsType because_Cache rename dependent_functionElimination equalitySymmetry dependent_set_memberEquality_alt independent_pairFormation equalityTransitivity productIsType equalityIstype applyLambdaEquality setElimination productElimination lambdaEquality_alt hyp_replacement independent_isectElimination Error :memTop,  natural_numberEquality imageElimination imageMemberEquality baseClosed independent_functionElimination

Latex:
\mforall{}X:j\mvdash{}.  \mforall{}A:\{X  \mvdash{}  \_\}.  \mforall{}B:\{X.A  \mvdash{}  \_\}.  \mforall{}x,y:\{X  \mvdash{}  \_:\mSigma{}  A  B\}.
    (\{X  \mvdash{}  \_:(Path\_\mSigma{}  A  B  x  y)\}  {}\mRightarrow{}  \{X  \mvdash{}  \_:(Path\_A  x.1  y.1)\})



Date html generated: 2020_05_20-PM-03_25_06
Last ObjectModification: 2020_04_07-PM-04_41_22

Theory : cubical!type!theory


Home Index