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God created the real numbers

(www.ethanheilman.com)
136 points Bogdanp | 2 comments | | HN request time: 0.001s | source
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andrewla ◴[] No.45067770[source]
I'm an enthusiastic Cantor skeptic, I lean very heavily constructivist to the point of almost being a finitist, but nonetheless I think the thesis of this article is basically correct.

Nature and the universe is all about continuous quantities; integral quantities and whole numbers represent an abstraction. At a micro level this is less true -- elementary particles specifically are a (mostly) discrete phenomenon, but representing the state even of a very simple system involves continuous quantities.

But the Cantor vision of the real numbers is just wrong and completely unphysical. The idea of arbitrary precision is intrinsically broken in physical reality. Instead I am off the opinion that computation is the relevant process in the physical universe, so approximations to continuous quantities are where the "Eternal Nature" line lies, and the abstraction of the continuum is just that -- an abstraction of the idea of having perfect knowledge of the state of anything in the universe.

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NoahZuniga ◴[] No.45068389[source]
You know it wouldn't be possible for us to tell the difference between a rational universe (one where all quantities are rational numbers) and a real universe (one where you can have irrational quantities).

The standard construction for the real numbers is to start with the rationals and "fill in all the holes". So why even bother with filling in the holes and instead just declare God created the rationals?

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tomrod ◴[] No.45071862[source]
Because the square root of 2 exists.
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tremon ◴[] No.45074324[source]
How does it exist though? Does it exist because we have a notation for it, or because we know its definition? Does the number 2 itself even exist? What does it mean to say that the number 2 exists?

Calculo, ergo sum?

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tomrod ◴[] No.45074868[source]
The number 2 simply exists independent of human intervention.
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1. chopin ◴[] No.45075824{3}[source]
I am not convinced. There are no two equal things in nature. Numbering things, say apples, is a completely human abstraction over two different things.
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2. tomrod ◴[] No.45086331[source]
How many units of protons does Helium have?