Jump to content

# Do numbers actually exist?

## Recommended Posts

I think it's more accurate to say that certain physical systems can be modeled using the mathematics of complex numbers. Whether complex numbers (or indeed, real numbers) exist in their own right is a matter of philosophy.

Edit: One representative discussion can be found here: http://philosophy.stackexchange.com/questions/451/do-numbers-exist-independently-from-observers.

Edited by John

• Replies 52
• Created
• Last Reply

#### Popular Days

I think it's more accurate to say that certain physical systems can be modeled using the mathematics of complex numbers. Whether complex numbers (or indeed, real numbers) exist in their own right is a matter of philosophy.

Edit: One representative discussion can be found here: http://philosophy.stackexchange.com/questions/451/do-numbers-exist-independently-from-observers.

It is not a matter if philosophy if you consider our label of numbers to be different than the inherent values themselves. Obviously, there are finite amounts of real objects.

##### Share on other sites

It is not a matter if philosophy if you consider our label of numbers to be different than the inherent values themselves.

That sounds like a philosophical argument. (Actually, I don't understand what you are trying to say, there.)

Obviously, there are finite amounts of real objects.

That is not obvious at all. The universe may be infinite, in which case it is filled with an infinite number of atoms.

##### Share on other sites

... Obviously, there are finite amounts of real objects.

What is 'real' and what is an 'object'? To the second question: the boundary of what constitutes an object, and how many there are, is arbitrary. Is a wall a plural of objects (bricks) or a single object?

##### Share on other sites

Buych778

Do numbers actually exist?

According to the site information the OP has not been since since posting this.

Upon rereading my post#3 I find I owe him, or her an apology for taking this thread down imaginary avenue towards complex street, fascinating though the scenery en route has been.

Post#1 clearly did not envision complex numbers, indeed it is not totally clear if even the full real number system was meant.

I am backtracking because in other mathematics forums there are currently debates going on as to whether numbers actually exist or can be realised in the real world. That seems to be the thrust of post#1 and the thread title.

My answer is yes, any real number can, in principle, be given a place in reality.

Edited by studiot
##### Share on other sites

That sounds like a philosophical argument. (Actually, I don't understand what you are trying to say, there.)

Assuming that you do not regard all of humanity's knowledge as an illusion, it in fact is not, because we can measure amounts from empirical observation. A physical amount is different than a concept of a symbol.

That is not obvious at all. The universe may be infinite, in which case it is filled with an infinite number of atoms.

Well, if you don't have eyes then I suppose it is more difficult to see. Regardless of whatever you may think, we empirically measure amounts of objects. To say otherwise would be to discard all knowledge that exists in humanity.

What is 'real' and what is an 'object'? To the second question: the boundary of what constitutes an object, and how many there are, is arbitrary. Is a wall a plural of objects (bricks) or a single object?

Objects that are real occupy nonzero quantities of dimensional space. If an object does not exist, it will not have any dimensional coordinates or capacity for empirical measurement. Take this apple I'm holding. It has 0 length, 0 width and 0 height, and no one can observe it, not even me. As a scientist, would you tell me that apple exists?

Edited by MWresearch
##### Share on other sites

Well, if you don't have eyes then I suppose it is more difficult to see. Regardless of whatever you may think, we empirically measure amounts of objects. To say otherwise would be to discard all knowledge that exists in humanity.

You said "there are finite amounts of real objects" not "there are finite amounts of real objects that [have] measured".

If the universe is infinite, there are an infinite number of real objects. Whether we can measure them or not.

##### Share on other sites

You said "there are finite amounts of real objects" not "there are finite amounts of real objects that [have] measured".

If the universe is infinite, there are an infinite number of real objects. Whether we can measure them or not.

Regardless of semantics, it is a fact that people have measured finite amounts of objects. Whether or not you want the parameters of measurement to encompass the whole universe is arbitrary.

If you want you can say all measurements are an illusion, but then you would have no basis to say all measurements are an illusion.

Edited by MWresearch
##### Share on other sites

I give up. I've never evaluated inequalities between vectors.

We can also induce a partial order on the complex numbers using the concentric circles of magnitude mentioned earlier, counting clockwise around each circle before moving to the "next." It's probably easier to think about this in terms of polar coordinates, in which we can say that $(|z_1|, \theta_1) < (|z_2|, \theta_2) \iff \left(|z_1| < |z_2|\right) \textnormal{ or } \left(|z_1| = |z_2| \textnormal{ and } \theta_1 < \theta_2\right)$. However, this is a bit unsatisfying since it means, among other things, that 1 < -1.
##### Share on other sites

mondie

I give up. I've never evaluated inequalities between vectors.

Complex numbers and geometric vectors are not the same.

Edited by studiot
##### Share on other sites

Regardless of semantics, it is a fact that people have measured finite amounts of objects. Whether or not you want the parameters of measurement to encompass the whole universe is arbitrary.

I was simply pointing out that "obviously, there are finite amounts of real objects" is neither obvious nor necessarily true. If you want to move the goalposts, that's fine with me.

If you want you can say all measurements are an illusion, but then you would have no basis to say all measurements are an illusion.

I don't want to say that. But thanks for the offer.

##### Share on other sites

I was simply pointing out that "obviously, there are finite amounts of real objects" is neither obvious nor necessarily true. If you want to move the goalposts, that's fine with me.

Anyway, according to our models, there are a finite amount of objects in any finite space. Since we cannot measure outside of the hubble volume, our measurements of the universe are confined to finite space.

I don't think we've ever encountered anything that we've "measured" as infinite. By it's very nature, it is impossible to count to infinity.

##### Share on other sites

I don't think we've ever encountered anything that we've "measured" as infinite. By it's very nature, it is impossible to count to infinity.

But we can (and do) include infinity in our counting.

There are as many real numbers between 0 and 1 as there are on the entire real number line.

This is why ordering is an important concept.

Because if we count reals in order from 0 to1 we have counted an infinity of numbers.

##### Share on other sites

But we can (and do) include infinity in our counting.

There are as many real numbers between 0 and 1 as there are on the entire real number line.

This is why ordering is an important concept.

Because if we count reals in order from 0 to1 we have counted an infinity of numbers.

According to that logic if I add 0 and 1 = 1 then I add an infinite amount of numbers. But, the sum of all numbers between 0 and 1 is infinity, you are therefore saying infinity=1.

There are infinite numbers between 0 and 1, but that doesn't mean we are distinguishing all of them in an infinite set just because we focus on the integers 0 and 1.

The act of counting itself as I am sure you know is much more complicated, you are actually doing the opposite of what you describe, specifically seeking out certain numbers of a general infinite set, not necessarily creating another infinite set.

##### Share on other sites

If numbers don't exist then how do these work?

http://en.wikipedia.org/wiki/Periodical_cicadas

And how did they choose primes?

##### Share on other sites

Anyway, according to our models, there are a finite amount of objects in any finite space. Since we cannot measure outside of the hubble volume, our measurements of the universe are confined to finite space.

I don't think we've ever encountered anything that we've "measured" as infinite. By it's very nature, it is impossible to count to infinity.

None of that is relevant to "obviously, there are finite amounts of real objects" being neither obvious nor necessarily true. That is all I was saying.

If you want to modify that statement to "obviously, there are finite amounts of real objects in the observable universe" then I have no objection.

##### Share on other sites

We can also induce a partial order on the complex numbers using the concentric circles of magnitude mentioned earlier, counting clockwise around each circle before moving to the "next." It's probably easier to think about this in terms of polar coordinates, in which we can say that $(|z_1|, \theta_1) < (|z_2|, \theta_2) \iff \left(|z_1| < |z_2|\right) \textnormal{ or } \left(|z_1| = |z_2| \textnormal{ and } \theta_1 < \theta_2\right)$. However, this is a bit unsatisfying since it means, among other things, that 1 < -1.

Just noticed this should say "counterclockwise" rather than "clockwise." We could go clockwise too, I suppose, but then we'd need $(|z_1|, \theta_1) < (|z_2|, \theta_2) \iff \left(|z_1| < |z_2|\right) \textnormal{ or } \left(|z_1| = |z_2| \textnormal{ and } \theta_1 > \theta_2\right)$, since angles increase in the counterclockwise direction.

I give up. I've never evaluated inequalities between vectors.

Well, in this case, the inequalities are just between magnitudes and angles, both of which are scalar values.

##### Share on other sites

If numbers don't exist then how do these work?

http://en.wikipedia.org/wiki/Periodical_cicadas

And how did they choose primes?

I'm arguing in favor of the existence of numbers, not against.

Or at least, I did not make an effort to say they do not exist, I merely wanted to know where imaginary numbers fit into existence from a mathematician's point of view.

##### Share on other sites

Or at least, I did not make an effort to say they do not exist, I merely wanted to know where imaginary numbers fit into existence from a mathematician's point of view.

At right angles to the reals.

##### Share on other sites

At right angles to the reals.

So does every single infinitesimal real value have a corresponding imaginary axis? How would that work in 3D space where you run out of ways to represent orthogonal dimensions?

##### Share on other sites

So does every single infinitesimal real value have a corresponding imaginary axis? How would that work in 3D space where you run out of ways to represent orthogonal dimensions?

It was actually a joke. But complex numbers can be represented as points on a plane with the x axis as the reals and the y axis as the imaginary number line.

http://mathworld.wolfram.com/ArgandDiagram.html

##### Share on other sites

It was actually a joke. But complex numbers can be represented as points on a plane with the x axis as the reals and the y axis as the imaginary number line.

http://mathworld.wolfram.com/ArgandDiagram.html

And?

##### Share on other sites

And?

And what? That was the answer to your question: where do imaginary numbers fit? (And also an explanation of my feeble "joke" of "at right angles").

##### Share on other sites

I was not asking anything akin to where imaginary numbers fit in mathematics, I was asking where they fit in physical reality.

##### Share on other sites

I was not asking anything akin to where imaginary numbers fit in mathematics, I was asking where they fit in physical reality.

They can describe real things in the same way that real numbers can. For example, when describing signals the imaginary part describes the phase (actually, its a little more complex than that).

## Create an account or sign in to comment

You need to be a member in order to leave a comment

## Create an account

Sign up for a new account in our community. It's easy!

Register a new account

## Sign in

Already have an account? Sign in here.

Sign In Now

×

• #### Activity

• Leaderboard
×
• Create New...

## Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.