claimroutineinferred_dep
Pi is irrational
Shows is irrational: a rational value would be an exact approximation
makes approximation errors nonzero for the pigeonhole step
Claim·§4 Choice of parameters and proof of Theorem~thm:main·inside thmIrrationality exponent of pi is 2
Statement (paper)
The number is irrational: if were rational, then exact representations with arbitrarily large denominators (unreduced fractions, zero error) would satisfy , which has been excluded for arbitrarily large , a contradiction.
In plain English
The number is irrational, since a rational value would give exact approximations with arbitrarily large denominators, which the preceding argument rules out.
Why it's here
Exact representations (unreduced, with zero error) satisfy the same approximation condition that the previous claim showed cannot hold for arbitrarily large , so rationality leads to a contradiction. This lets the later pigeonhole step assume is irrational, so the approximation errors are nonzero.
Classified routine:
This follows directly from claim-thm-main-4: if π were rational, unreduced fractions would give exact approximations with arbitrarily large denominators, contradicting the preceding exclusion.
Uses
Used by
Sources
PaperOpen
- Section
- §4 Choice of parameters and proof of Theorem~thm:main
- Page
- —
- Label
—- Line
sections/conclusion.tex:136
Leannot aligned
Phase 2 aligns this node to a Lean declaration.
Friction
- infoinferred_depoutline: "Exact approximations exclude rationality" rests on claim-thm-main-4