Nuprl Lemma : idom_alt_char

∀r:CRng
  ((∀x,y:|r|.  Dec(x = y ∈ |r|))
  ⇒ (IsIntegDom(r) ⇐⇒ 0 ≠ 1 ∈ |r|  ∧ (∀u,v:|r|.  (u = 0 ∈ |r|) ∨ (v = 0 ∈ |r|) supposing (u * v) = 0 ∈ |r|)))


Proof




Definitions occuring in Statement :  integ_dom_p: IsIntegDom(r),  crng: CRng,  rng_one: 1,  rng_times: *,  rng_zero: 0,  rng_car: |r|,  decidable: Dec(P),  uimplies: b supposing a,  infix_ap: x f y,  all: ∀x:A. B[x],  iff: P ⇐⇒ Q,  nequal: a ≠ b ∈ T ,  implies: P ⇒ Q,  or: P ∨ Q,  and: P ∧ Q,  equal: s = t ∈ T
Definitions unfolded in proof :  integ_dom_p: IsIntegDom(r),  all: ∀x:A. B[x],  implies: P ⇒ Q,  iff: P ⇐⇒ Q,  and: P ∧ Q,  nequal: a ≠ b ∈ T ,  not: ¬A,  false: False,  member: t ∈ T,  prop: ℙ,  uall: ∀[x:A]. B[x],  crng: CRng,  rng: Rng,  uimplies: b supposing a,  infix_ap: x f y,  so_lambda: λ2x.t[x],  so_apply: x[s],  rev_implies: P ⇐ Q,  or: P ∨ Q,  decidable: Dec(P),  guard: {T}
Lemmas referenced :  equal_wf,  rng_car_wf,  rng_zero_wf,  rng_one_wf,  rng_times_wf,  nequal_wf,  all_wf,  not_wf,  infix_ap_wf,  isect_wf,  or_wf,  decidable_wf,  crng_wf
Rules used in proof :  sqequalSubstitution,  sqequalRule,  sqequalReflexivity,  sqequalTransitivity,  computationStep,  lambdaFormation,  independent_pairFormation,  cut,  thin,  sqequalHypSubstitution,  hypothesis,  independent_functionElimination,  voidElimination,  introduction,  extract_by_obid,  isectElimination,  setElimination,  rename,  hypothesisEquality,  because_Cache,  isect_memberFormation,  axiomEquality,  applyEquality,  productEquality,  lambdaEquality,  functionEquality,  productElimination,  dependent_functionElimination,  equalityTransitivity,  equalitySymmetry,  unionElimination,  inrFormation,  inlFormation,  independent_isectElimination

Latex:
\mforall{}r:CRng
    ((\mforall{}x,y:|r|.    Dec(x  =  y))
    {}\mRightarrow{}  (IsIntegDom(r)  \mLeftarrow{}{}\mRightarrow{}  0  \mneq{}  1  \mmember{}  |r|    \mwedge{}  (\mforall{}u,v:|r|.    (u  =  0)  \mvee{}  (v  =  0)  supposing  (u  *  v)  =  0)))



Date html generated: 2017_10_01-AM-08_18_26
Last ObjectModification: 2017_02_28-PM-02_03_20

Theory : rings_1


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