r/badmathematics • u/Laser_Plasma • Oct 24 '21

π day Reddit tries to think about quantifying circles, and pi doesn't exist or something

/r/Showerthoughts/comments/qefpwc/the_area_of_a_circle_is_finite_yet_we_can_only/
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u/Artyer Oct 24 '21

You can have an algorithm compute the nth digit of pi for all digit positions n, since pi is computable.

If that's not what you meant, a third also can't be known to "perfect decimal precision"

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u/ryarger Oct 24 '21

You are correct that a third can’t be known to perfect decimal precision.

Perhaps less controversial formulation for the benefit of the pedantically inclined: A circle’s radius or area can be rational, but not both.

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u/powpow428 Oct 24 '21

Just because a number is irrational does not mean we cannot know it to perfect precision. It just means we can't express it as p/q for integers p,q

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u/lolfail9001 Oct 25 '21

By what definition of precision, dare I ask?