Nuprl Lemma : groupoid_inv

∀[G:Groupoid]
  ∀x,y:cat-ob(cat(G)). ∀f:cat-arrow(cat(G)) x y.
    (((cat-comp(cat(G)) x y x f groupoid-inv(G;x;y;f)) = (cat-id(cat(G)) x) ∈ (cat-arrow(cat(G)) x x))
    ∧ ((cat-comp(cat(G)) y x y groupoid-inv(G;x;y;f) f) = (cat-id(cat(G)) y) ∈ (cat-arrow(cat(G)) y y)))


Proof




Definitions occuring in Statement :  groupoid-inv: groupoid-inv(G;x;y;x_y),  groupoid-cat: cat(G),  groupoid: Groupoid,  cat-comp: cat-comp(C),  cat-id: cat-id(C),  cat-arrow: cat-arrow(C),  cat-ob: cat-ob(C),  uall: ∀[x:A]. B[x],  all: ∀x:A. B[x],  and: P ∧ Q,  apply: f a,  equal: s = t ∈ T
Definitions unfolded in proof :  guard: {T},  pi2: snd(t),  groupoid-inv: groupoid-inv(G;x;y;x_y),  pi1: fst(t),  groupoid-cat: cat(G),  groupoid: Groupoid,  cand: A c∧ B,  and: P ∧ Q,  all: ∀x:A. B[x],  member: t ∈ T,  uall: ∀[x:A]. B[x]
Lemmas referenced :  groupoid_wf,  cat-ob_wf,  groupoid-cat_wf,  cat-arrow_wf
Rules used in proof :  because_Cache,  axiomEquality,  independent_pairEquality,  dependent_functionElimination,  lambdaEquality,  hypothesisEquality,  isectElimination,  lemma_by_obid,  applyEquality,  independent_pairFormation,  hypothesis,  sqequalRule,  rename,  setElimination,  thin,  productElimination,  sqequalHypSubstitution,  lambdaFormation,  cut,  introduction,  isect_memberFormation,  sqequalReflexivity,  computationStep,  sqequalTransitivity,  sqequalSubstitution

Latex:
\mforall{}[G:Groupoid]
    \mforall{}x,y:cat-ob(cat(G)).  \mforall{}f:cat-arrow(cat(G))  x  y.
        (((cat-comp(cat(G))  x  y  x  f  groupoid-inv(G;x;y;f))  =  (cat-id(cat(G))  x))
        \mwedge{}  ((cat-comp(cat(G))  y  x  y  groupoid-inv(G;x;y;f)  f)  =  (cat-id(cat(G))  y)))



Date html generated: 2016_05_18-AM-11_54_28
Last ObjectModification: 2015_12_28-PM-02_23_11

Theory : small!categories


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