Nuprl Lemma : approx-fixpoint-unit-ball-0

∀n:ℕ+. ∀f:{f:B(n) ⟶ B(n)| 
           (∀e:{e:ℝ| r0 < e} . ∃del:{del:ℝ| r0 < del} . ∀x,y:B(n).  ((d(x;y) < del) ⇒ (d(f x;f y) < e)))
           ∧ (¬(∀x:B(n). f x ≠ x))} . ∀e:{e:ℝ| r0 < e} .
  ∃t:B(n) ⟶ 𝔹
   ((∀p:B(n). ((↑(t p)) ⇒ (↓d(f p;p) < e))) ∧ (↓∃k:ℕ+. ∃q:unit-ball-approx(n;k). (↑(t approx-ball-to-ball(k;q)))))


Proof




Definitions occuring in Statement :  approx-ball-to-ball: approx-ball-to-ball(k;p),  unit-ball-approx: unit-ball-approx(n;k),  real-unit-ball: B(n),  real-vec-sep: a ≠ b,  real-vec-dist: d(x;y),  rless: x < y,  int-to-real: r(n),  real: ℝ,  nat_plus: ℕ+,  assert: ↑b,  bool: 𝔹,  all: ∀x:A. B[x],  exists: ∃x:A. B[x],  not: ¬A,  squash: ↓T,  implies: P ⇒ Q,  and: P ∧ Q,  set: {x:A| B[x]} ,  apply: f a,  function: x:A ⟶ B[x],  natural_number: $n
Definitions unfolded in proof :  all: ∀x:A. B[x],  member: t ∈ T,  uall: ∀[x:A]. B[x],  uimplies: b supposing a,  rneq: x ≠ y,  guard: {T},  or: P ∨ Q,  iff: P ⇐⇒ Q,  and: P ∧ Q,  rev_implies: P ⇐ Q,  implies: P ⇒ Q,  less_than: a < b,  squash: ↓T,  less_than': less_than'(a;b),  true: True,  nat: ℕ,  nat_plus: ℕ+,  rless: x < y,  sq_exists: ∃x:A [B[x]],  decidable: Dec(P),  not: ¬A,  satisfiable_int_formula: satisfiable_int_formula(fmla),  exists: ∃x:A. B[x],  false: False,  top: Top,  prop: ℙ,  subtype_rel: A ⊆r B,  real-unit-ball: B(n),  isr: isr(x),  assert: ↑b,  ifthenelse: if b then t else f fi ,  bfalse: ff,  btrue: tt,  sq_stable: SqStable(P),  sq_type: SQType(T),  int_nzero: ℤ-o,  nequal: a ≠ b ∈ T ,  rdiv: (x/y),  uiff: uiff(P;Q),  req_int_terms: t1 ≡ t2,  cand: A c∧ B,  so_lambda: λ2x.t[x],  so_apply: x[s],  real-vec-sep: a ≠ b,  rge: x ≥ y,  stable: Stable{P}
Lemmas referenced :  rmul_preserves_rless,  rdiv_wf,  rless-int,  rless-cases,  rmul_wf,  int-to-real_wf,  real-vec-dist_wf,  nat_plus_properties,  decidable__le,  full-omega-unsat,  intformand_wf,  intformnot_wf,  intformle_wf,  itermConstant_wf,  itermVar_wf,  intformless_wf,  istype-int,  int_formula_prop_and_lemma,  istype-void,  int_formula_prop_not_lemma,  int_formula_prop_le_lemma,  int_term_value_constant_lemma,  int_term_value_var_lemma,  int_formula_prop_less_lemma,  int_formula_prop_wf,  istype-le,  real-unit-ball_wf,  istype-true,  bfalse_wf,  btrue_wf,  nat_plus_subtype_nat,  istype-assert,  squash_wf,  rless_wf,  nat_plus_wf,  unit-ball-approx_wf,  assert_wf,  approx-ball-to-ball_wf,  real_wf,  real-vec-sep_wf,  itermSubtract_wf,  itermMultiply_wf,  rinv_wf2,  sq_stable__rless,  subtype_base_sq,  int_subtype_base,  decidable__equal_int,  intformeq_wf,  int_formula_prop_eq_lemma,  int_term_value_mul_lemma,  nequal_wf,  radd-preserves-rless,  radd_wf,  itermAdd_wf,  rless_functionality,  req_transitivity,  rmul-rinv3,  req-iff-rsub-is-0,  real_polynomial_null,  real_term_value_sub_lemma,  real_term_value_mul_lemma,  real_term_value_const_lemma,  real_term_value_var_lemma,  int-rinv-cancel,  real_term_value_add_lemma,  small-reciprocal-real,  rmin_wf,  rmin_strict_ub,  rmin-rleq,  rless_transitivity1,  decidable__lt,  real-unit-ball-totally-bounded1,  mul_nat_plus,  istype-less_than,  decidable__exists-unit-ball-approx,  multiply_nat_wf,  decidable__assert,  isr_wf,  rneq-int,  rless_transitivity2,  rsub_wf,  rless-implies-rless,  rleq_weakening,  rleq_wf,  rless_functionality_wrt_implies,  rleq_weakening_equal,  stable__rleq,  false_wf,  not_wf,  not-rless,  minimal-double-negation-hyp-elim,  minimal-not-not-excluded-middle,  real-vec-triangle-inequality,  real-vec-dist-symmetry,  req_weakening,  rleq_weakening_rless,  radd_functionality_wrt_rless2,  radd_functionality_wrt_rleq,  radd_functionality_wrt_rless1,  rless_irreflexivity
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  lambdaFormation_alt,  cut,  introduction,  extract_by_obid,  sqequalHypSubstitution,  dependent_functionElimination,  thin,  because_Cache,  isectElimination,  independent_isectElimination,  sqequalRule,  hypothesis,  inrFormation_alt,  productElimination,  independent_functionElimination,  natural_numberEquality,  independent_pairFormation,  imageMemberEquality,  hypothesisEquality,  baseClosed,  closedConclusion,  dependent_set_memberEquality_alt,  setElimination,  rename,  unionElimination,  approximateComputation,  dependent_pairFormation_alt,  lambdaEquality_alt,  int_eqEquality,  isect_memberEquality_alt,  voidElimination,  universeIsType,  applyEquality,  inhabitedIsType,  equalityTransitivity,  equalitySymmetry,  functionExtensionality,  equalityIstype,  functionIsType,  productIsType,  productEquality,  setIsType,  imageElimination,  instantiate,  cumulativity,  intEquality,  sqequalBase,  minusEquality,  multiplyEquality,  unionEquality,  functionEquality,  unionIsType

Latex:
\mforall{}n:\mBbbN{}\msupplus{}.  \mforall{}f:\{f:B(n)  {}\mrightarrow{}  B(n)| 
                      (\mforall{}e:\{e:\mBbbR{}|  r0  <  e\} 
                            \mexists{}del:\{del:\mBbbR{}|  r0  <  del\}  .  \mforall{}x,y:B(n).    ((d(x;y)  <  del)  {}\mRightarrow{}  (d(f  x;f  y)  <  e)))
                      \mwedge{}  (\mneg{}(\mforall{}x:B(n).  f  x  \mneq{}  x))\}  .  \mforall{}e:\{e:\mBbbR{}|  r0  <  e\}  .
    \mexists{}t:B(n)  {}\mrightarrow{}  \mBbbB{}
      ((\mforall{}p:B(n).  ((\muparrow{}(t  p))  {}\mRightarrow{}  (\mdownarrow{}d(f  p;p)  <  e)))
      \mwedge{}  (\mdownarrow{}\mexists{}k:\mBbbN{}\msupplus{}.  \mexists{}q:unit-ball-approx(n;k).  (\muparrow{}(t  approx-ball-to-ball(k;q)))))



Date html generated: 2019_10_30-AM-11_29_07
Last ObjectModification: 2019_07_30-PM-00_30_01

Theory : real!vectors


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