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

∀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 :  member: t ∈ T,  approx-fixpoint-unit-ball-0,  rless-cases,  rmul_preserves_rless,  rless-int,  rless_functionality,  radd-preserves-rless,  sq_stable__rless,  rmul_functionality_wrt_rless,  rless-iff4,  rless-iff-large-diff,  radd_functionality_wrt_rless2,  rinv-positive,  regular-less-iff,  decidable__le,  any: any x
Lemmas referenced :  approx-fixpoint-unit-ball-0,  rless-cases,  rmul_preserves_rless,  rless-int,  rless_functionality,  radd-preserves-rless,  sq_stable__rless,  rmul_functionality_wrt_rless,  rless-iff4,  rless-iff-large-diff,  radd_functionality_wrt_rless2,  rinv-positive,  regular-less-iff,  decidable__le
Rules used in proof :  introduction,  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  cut,  instantiate,  extract_by_obid,  hypothesis,  sqequalRule,  thin,  sqequalHypSubstitution,  equalityTransitivity,  equalitySymmetry

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_10
Last ObjectModification: 2019_07_30-PM-00_31_32

Theory : real!vectors


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