# Difference between revisions of "Talk:Infinity"

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:Merriam-Webster's definition of infinity is unusually inadequate: "an indefinitely great number or amount." The essence of infinity is not that it is indefinite.--[[User:Aschlafly|Andy Schlafly]] ([[User talk:Aschlafly|talk]]) 00:36, 18 May 2018 (EDT) | :Merriam-Webster's definition of infinity is unusually inadequate: "an indefinitely great number or amount." The essence of infinity is not that it is indefinite.--[[User:Aschlafly|Andy Schlafly]] ([[User talk:Aschlafly|talk]]) 00:36, 18 May 2018 (EDT) | ||

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+ | == Bernhard Riemann == | ||

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+ | ''Inherent in the concept of infinity is the concept of infinitesimal: infinity small. Bernhard Riemann identified the sum of infinitesimal strips of area under a function to establish a rigorous definition of the integral, now known as the Riemann Integral. '' | ||

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+ | I think that this misrepresents Bernhard Riemann's ideas: | ||

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+ | The infinitesimals were tools of the creative geniuses of the 18th century, as Euler, Leibniz, and Newton. Riemann took a step away: he does not talk about things which ''are'' infinitely small, but which ''become'' infinitely small - using the idea of limits. Therefore, the integral is not the sum of infinitesimal strips, but the limit of finite sums of small stripes, becoming smaller and smaller. | ||

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+ | That may sound like hair-splitting, but his approach could be rigorously formalized quite easily, while this was much more difficult for infinitesimals.--[[User:AugustO|AugustO]] ([[User talk:AugustO|talk]]) 10:36, 30 July 2018 (EDT) |

## Revision as of 08:36, 30 July 2018

This article refers to infinity as both being a number, and not being a number. Clarify. RDre 14:12, 11 April 2007 (EDT)

- Can you fix it? --Ed Poor 14:13, 11 April 2007 (EDT)

- I'm not qualified to judge which it is, but it's been dealt with now. RDre 14:19, 11 April 2007 (EDT)

- Good start, but ...
- In the early 1600's Galileo began to show signs of a modern attitude toward the infinite, when he proposed that "infinity should obey a different arithmetic than finite numbers." But it was not until the late 19th century that Georg Cantor (1845-1918), a German mathematician, finally put infinity on a firm logical foundation and described a way to do arithmetic with infinite quantities useful to mathematics. [1]

- We better start over. --Ed Poor 14:50, 11 April 2007 (EDT)

- It wasn't that bad. Infinity is not a number, but it
*is*greater than any real number. Tsumetai 14:52, 11 April 2007 (EDT)

- It wasn't that bad. Infinity is not a number, but it

XD yea. I had my fun. Pie5 21:04, 4 December 2007 (EST)

## Contents

## Limit at the top of the page

Wow...Just wow...You guys claim that
is infinite.

...I don't know what to say to this. **Any student who's had more than a week of calculus knows that this is incorrect. ** The correct statement is the limit from the *right.* The way you have it, the limit is undefined. Andy Schlafly, weren't you supposedly trained in a semi-technical field..? I'm amazed about the mistakes you make. Both here and on your "counterexamples to relativity" page....Wow... AndyFrankinson 20:02, 14 October 2011 (EDT)

## Rough and sloppy

I need a lot of help with this article. It had a mention of division by zero, which all mathematicians (and most math students) know is a forbidden operation. Don't put nonsense like that in math articles. --Ed Poor ^{Talk} 10:47, 18 September 2009 (EDT)

- I like your new edits. What else are you thinking of adding? I will help where I can. --MarkGall 11:35, 18 September 2009 (EDT)

## My recent changes

I hope I have beaten the readers over the head sufficiently with the dictum that infinity is not a number, and hence dealt with Ed's complaint about this. You just don't divide by zero. Period. It's illegal. If you see an equation that appears to be dividing by zero, that equation is wrong.

I have taken out the stuff about "sample size". That refers to the size of a set in the field of statistics. We already cover set cardinality in general.

I have taken out the reference to "elementary techniques". That was meaningless, and seemed to be invoking the notion of "elementary proof", which is a page that needs a lot of work. Invoking that notion from here is just confusing the issue. Unless, of course, someone can clarify what that means, and give citations.

I can't figure out how to get spacing between the "math" parts and the "plain" parts in my list of 5 equations, so it looks horrible. Does anyone know how to do this? I know how in LaTeX, but that's way too complicated for a wiki, and probably wouldn't work.

PatrickD 15:35, 19 September 2009 (EDT)

## My concept of infinity

To me, the only infinity is that in which God has lived before creating us, and that which He grants us in Heaven. That's all I have to say about it. --Pious (talk) 00:47, 20 April 2017 (EDT)

## Were the Greeks flat out wrong?

This page seems to go at the Greeks in a biased way. It says they were "flat out wrong" about infinity -- even if this is correct, I think this sentence certainly needs re-phrasing. Anyways, while I think that God is certainly infinite, I do not accept that infinity can exist in the natural world, and so I consider that the Greeks were, to some extent, correct. Philosophers are generally in agreement with me as well.

## Definition

The definition needs improvement. Some infinities are greater than others.--Andy Schlafly (talk) 01:00, 12 May 2018 (EDT)

- Merriam-Webster's definition of infinity is unusually inadequate: "an indefinitely great number or amount." The essence of infinity is not that it is indefinite.--Andy Schlafly (talk) 00:36, 18 May 2018 (EDT)

## Bernhard Riemann

*Inherent in the concept of infinity is the concept of infinitesimal: infinity small. Bernhard Riemann identified the sum of infinitesimal strips of area under a function to establish a rigorous definition of the integral, now known as the Riemann Integral. *

I think that this misrepresents Bernhard Riemann's ideas:

The infinitesimals were tools of the creative geniuses of the 18th century, as Euler, Leibniz, and Newton. Riemann took a step away: he does not talk about things which *are* infinitely small, but which *become* infinitely small - using the idea of limits. Therefore, the integral is not the sum of infinitesimal strips, but the limit of finite sums of small stripes, becoming smaller and smaller.

That may sound like hair-splitting, but his approach could be rigorously formalized quite easily, while this was much more difficult for infinitesimals.--AugustO (talk) 10:36, 30 July 2018 (EDT)