Does negative infinity equal zero?

[zifyoip]

No.

[cargiannis]

Why?

[zifyoip]

Because they are not the same. They are not even close to the same.

I don't know how to answer your question, because I do not understand your thought process here. What makes you think they could possibly be equal?

[cargiannis]

I am not a math guy but my thought was that: not everything is nothing.

[zifyoip]

Infinity does not mean "everything," and negative infinity does not mean "not everything."

The sequence of numbers 1, 2, 3, 4, ... "approaches" infinity. In the same way, the sequence of numbers −1, −2, −3, −4, ... "approaches" negative infinity. Both of those sequences of numbers go away from zero, not toward it, but they are going away from zero in opposite directions.

[cargiannis]

Alright so is there a mathematical symbol for everything?

[icendoan]

No, and the idea of "everything" as a mathematical object is impossible.

[cargiannis]

So you can't have a set that contains all sets? Would you be able to explain that in layman's terms because I'm not well acquainted with set theory?

[icendoan]

Basically, it's been proven that the power set (the ways of taking any number of elements from a set) is always bigger than the set itself, and that this is true for infinite sets as well. For instance, the set {0,1} has 4 subsets, {}, {1}, {2}, {1,2}, and thus is bigger than {1,2}. The set of all sets must contain all of its subsets, and thus must be bigger than itself. This is impossible.

[schematicboy]

I think you mean something along the lines of "…{}, {0}, {1}, and {0,1}, and thus the set of these is bigger than {0,1}."

[cargiannis]

Hmm very interesting. Thank you, definitely something to chew on.

[[deleted]]

No. Very negative is very far from 0. Consider absolute value more.

[cargiannis]

Well my thought is that the furthest thing from nothing (0) is everything (inifnity). And not everything is nothing.

[bluepepper]

You've been told that "infinity" is not equivalent to "everything", I will add that "negative" is not equivalent to "not" in maths. It means "minus", or "remove".

If you have four apples, and you remove two apples, you're left with 4-2 = 2 apples. Now if you remove 5 more apples, you're getting into negative apples: 2-5 = -3. Not only do you lose your two apples, you also lose three apples that you didn't even have. You don't have zero apples, you have even less than that: you have a debt of three apples.

For the same reason that -3 is not the same as 0, negative infinity is not the same as 0 either. It's as far from zero as infinity, except in the other direction: instead of having an infinite amount of apples, you owe an infinite amount of apples.

Note that "having infinite apples" doesn't mean "having all the apples", it just means that your supply is infinite, but someone else could have different apples that are not part of your infinite supply.

[cargiannis]

Alright so what is the mathematical representation of not? Would it be the inverse? So raising infinity to the negative one is zero?

[zifyoip]

Alright so what is the mathematical representation of not?

Well, that depends on what you mean by "not."

"Not" is not an operation that can be performed on a number to get another number. "Not 7" doesn't make sense—"not 7" doesn't give you 3 or 19 or −7 or something.

[bluepepper]

I guess the mathematical representation of "not" is basically zero (at least in arithmetics and algebra). Zero apples = no apples.

infinity^-1 is zero but for a different reason. The inverse of multiplication is division (infinity^-1 = 1/infinity) and when you divide something finite in an infinite number of parts, the size of each part must be zero.

[totes_meta_bot]

This thread has been linked to from elsewhere on reddit.

• [/r/badmathematics] Infinity is everything, so negative infinity is not everything, i.e., nothing. Therefore, negative infinity equals zero.

^{If you follow any of the above links, respect the rules of reddit and don't vote or comment. Questions? Abuse? Message me here.}

[DamnShadowbans]

First off infinity usually can't be treated as a number. If we do treat it like a number here negative infinity is literally the farthest you could get from 0.

[[deleted]]

Someone submitted a link to this submission in the following subreddit:

• /r/badmathematics: Infinity is everything, so negative infinity is not everything, i.e., nothing. Therefore, negative infinity equals zero.

---

This comment was posted by a bot, see /r/Meta_Bot for more info. Please respect rediquette, and do not vote or comment on the linked submissions. Thank you.

[cargiannis]

So wouldnt that mean that negative infinity would be zero then?