Where does the universe end?

Eliot · 6 Aug 2009 at 13:06

infinity is a mathematical concept, and is impossible. fact

Gilly · 6 Aug 2009 at 13:07

taz488 said:
http://en.wikipedia.org/wiki/0.999...#Algebraic

So because maths can't deal with infinity it equals 1?

Well, it doesn't.

taz488 said:
and it annoys me when people say 'oh the universe cannot be infinate, it just cant'.

yes it can.

No it can't.

Eliot said:
infinity is a mathematical concept, and is impossible. fact

Prove it

lemonkettaz · 6 Aug 2009 at 13:12

I'm safe in the knowledge that obviously everyone here is qualified to back up their points of view with facts

The known universe isnt infinite... hasn't this been proven?

w11tho · 6 Aug 2009 at 13:12

Gilly said:
So because maths can't deal with infinity it equals 1?

Well, it doesn't.

From what authority do you speak? What makes you think "maths can't deal with infinity"?

Nanoman · 6 Aug 2009 at 13:13

If the universe is expanding then surely it can't be infinite?

taz488 · 6 Aug 2009 at 13:13

Gilly said:
So because maths can't deal with infinity it equals 1?
Well, it doesn't.

It does deal with it, it denotes an unbounded limit. And 0.999... is proven rigorously to be the same real number as 1.

Gilly said:
No it can't.

Prove it

Well its your word against mine im affraid. I said it first, so you can prove it first

Eliot · 6 Aug 2009 at 13:16

its quite easy to prove that the universe isnt infinite, if its constantly increasing in size at the speed of light (or faster) then if it was infinite about 15 mins ago when someone on here said it was. since then its grown quite vastly in size and so it couldnt have been infinte 15 minutes ago

(quick edit there lol accidently typed is infinite instead of isnt)

Gilly · 6 Aug 2009 at 13:16

taz488 said:
It does deal with it, it denotes an unbounded limit. And 0.999... is proven rigorously to be the same real number as 1.

Except it isn't, there's always a little bit more.

taz488 said:
Well its your word against mine im affraid. I said it first, so you can prove it first

However you were refuting someone else's statement, ergo need to prove it first using your own logic

Eliot · 6 Aug 2009 at 13:18

opps double post kinda.

D D Danneh · 6 Aug 2009 at 13:22

w11tho said:
From what authority do you speak? What makes you think "maths can't deal with infinity"?

0.99r = 1 is a limitation of our number system, nothing to do with "there can't be infinity".

If the world had used a base 3 number system, the whole "1 / 3 = 0.3r so 3/3 = 1 = 0.9r" would be wrong, because 10 / 3 would equal 1, so 3/3 would be 10, and not 2.22222222.

I reckon the universe is infinite. Tough to say why, but I think it is.

RDM · 6 Aug 2009 at 13:23

Nitefly said:
I find that if you don't ask how everything within our reality came into being, then you have to accept that everything just 'is' and 'has always been'. I'm not sure what's more ridiculous, everything we know has been around forever with no starting point, or that someone put on their wizard robes and created everything in 7 days.

To be honest either way you are left with the same question, the God thing just moves it back one stage. Either something suddenly appeared from nothing or something has always existed. Either one causes issues!

Amnesia · 6 Aug 2009 at 13:24

i'd be more interested in finding out if there were different (or even alternate) time lines so we could time travel.

i want to see jesus

taz488 · 6 Aug 2009 at 13:26

Can we have an infinite universe for example? The answer is no, the universe is finite. Stephen Hawking in 'A Brief History of Time' (1989 page 44) describes the universe as being "finite but unbounded". The simplest answer is that as the universe is known to be expanding, it cannot possibly be infinite. To be precise, the dictionary definition of the word universe is "all that is. The whole system of things." In this sense the universe is not expanding into anything other than itself, for whatever it is expanding into is part of the universe, there being nothing else but the universe. However, for the sake of simplicity, I am referring only to our Big Bang expanding universe as 'the universe'. (Even if you happen to disagree with the Big Bang theory, the term 'universe' will still have the same meaning here, as it refers to 'our' universe only, and does not include whatever may or may not exist outside of it.) I will try and explain a finite universe as some people understandably have problems with it.

oh how wrong i was...

but still maths deals with infinity, it just doesnt exist in the real world.

w11tho · 6 Aug 2009 at 13:26

D D Danneh said:
0.99r = 1 is a limitation of our number system, nothing to do with "there can't be infinity".

I'm not sure I was clear - I know 1 and 0.9r represent exactly the same real number. I was asking the member Gilly, from what authority he speaks because he seems to think he knows better than the entire mathematical community, and their predecessors.

D.P. · 6 Aug 2009 at 13:35

w11tho said:
I'm not sure I was clear - I know 1 and 0.9r represent exactly the same real number. I was asking the member Gilly, from what authority he speaks because he seems to think he knows better than the entire mathematical community, and their predecessors.

If Gilly can prove it then there is a Nobel prize waiting for him

D D Danneh · 6 Aug 2009 at 13:44

w11tho said:
I'm not sure I was clear - I know 1 and 0.9r represent exactly the same real number.

And what I was saying is that 0.99r is not the same number as 1, it is simply a limitation of the base 10 number system that leads us to say they are so similar, they might as well be the same number in practical use.

Gilly · 6 Aug 2009 at 13:47

w11tho said:
I'm not sure I was clear - I know 1 and 0.9r represent exactly the same real number. I was asking the member Gilly, from what authority he speaks because he seems to think he knows better than the entire mathematical community, and their predecessors.

0.9r and 1 are not the same number, else they'd both be written the same way

Nitefly · 6 Aug 2009 at 13:51

Gilly said:
0.9r and 1 are not the same number, else they'd both be written the same way

Indeed, if 0.9r is written to be less in value than one, then surely the logical conclusion is that... 0.9r is less that one?

Not that I'm a maths wizz or anything, naturally.

taz488 · 6 Aug 2009 at 13:52

Nitefly said:
Indeed, if 0.9r is written to be less in value than one, then surely the logical conclusion is that... 0.9r is less that one?

Not that I'm a maths wizz or anything, naturally.

but if you wrote 0.999r < 1 youd be wrong.

utajoker · 6 Aug 2009 at 13:56

were ever it ends there is a little chef.