[philbo1965uk]

Instead of me getting up peoples noses im not replying,can someone else point out his presumptions,

[5614]

im not sure whos making the assumptions you are talking about, but:

space is infinite, however we say that space has edges... these edges are the furthest bit of matter in a certain direction. beyond that is matterless space - a true vacum. so when a comet or something goes past the 'edge' of space, it creates a new edge.
(i dont know how matterless waves and particles e.g. EM radiation and photons/phonons fit into this though)

can you accept that? (re-reading that sounds rude, its meant in a friendly way :D)

infinite is not a human, everything human has a limit or boundary, it is a non-human concept 'infinit' (except in maths...) is not possible to imagine, but it is scientificly prooven, we are an advance nation (in a sense) we can proove things like this and know they are true.
and i know your there thinking that they used to think the world was flat... in a few hundred years this will seem like stupid rubbish, however somewhere the stupid rubbish will stop coming out... and that time has already happened, we are advance enough to know stuff like this. (repeat top two paragraphs for a good effect!)

[philbo1965uk]

5614 apart from reminding me just how confusing my posts must be,you surpass my expectations just what the heck are you talking about.
(quote)im not sure who is making the assumptions you are talking about.....
and i know your thinking that they used to think the world was flat...in a few hundred years this will seem like stupid rubbish,however somewhere the stupid rubbish will stop coming out...and that time has already happened,we are advance enough to know stuff like that(end quote)
Now i take it for granted regardless of the field of ones expertise,most here have an average intelligence(though my spelling at times is fun lol)
so when i pass the buck and ask others to point out someones presumptions(pssst there not based on fact mate...)
I did not expect someone to not (a)understand the question (b) make a conceited remark like we are advanced enough to know stuff like this.( mmm were does the we fit into that...you dont include yourself in that statement do you)

[Severian]

Well, lets take it one step at a time shall we philbo?

1. To which post were you refering (presumptions)? (They are numbered.) Post 40?

2. Which 'presumptions' do you see and object to?

[albymangles]

I think the presumptions they were referring to were (post 40)

1. you assume our universe to extend equally in all directions to infinity
2. space time to extend outwards in all directions along straight lines to infinity
3. that this entire fabric of space-time was created at the very instant of the big-bang

and I'm not even going to try with post 42... space having an 'edge' that is the furthest bit of matter in our universe? this seems to me an extremely simplistic and naive view of things (uncertainty principle anyone?!?).

oh and before anyone points to my previous thread, i do in fact agree with them (post 40), I'm just not so sure that our universe is not curved in on itself making it thus finite (but there would still be no realistic boundary).

[Severian]

Quote

I'm just not so sure that our universe is not curved in on itself making it thus finite (but there would still be no realistic boundary).

If you believe the experimental data, then it's not. WMAP has shown that the universe is open - not closed.

[philbo1965uk]

so people can see them and its not me just antagonising....

[ydoaPs]

personally, i think WMAP was a waste of money. it is based on a small part of our universe.

[Ophiolite]

yourdadonapogos said:

personally, i think WMAP was a waste of money. it is based on a small part of our universe.

Could you expand on that please, if you have rough figures to hand? How much money? How small? Thanks.

[MadScientist]

The way I see things...

The universe is now aged at 13.7 billion years isn't it now??
But the universe is too big to have grown this much in that time, then they introduced this "inflation stage" of development and everything fitted into place again. Back then it could expand quicker than it does now.

What's outside the universe?? I LOVE this one!!
You can't say there is a void or just nothing outside our universe. Because even nothing not even a void could exist outside it.
So to be accurate you've got to say, there's nothing at all not even nothing outside out universe, haven't you??


What if there was a galaxy right on the edge of the universe??
I think if I was on a planet in that galaxy I'd be packing my bags and legging it as far away as possible. So maybe we'll find out about the edge of the universe when the fleet of alien ships come whizzing by, stopping to tell us we're going the wrong way. ;)


Another theory I have is that any particles trying to become a part of this nothing that's not even nothing, will be repelled with more force than it went in with.
But I mentioned that in another thread about tachyons. ;)

[Severian]

yourdadonapogos said:

personally, i think WMAP was a waste of money. it is based on a small part of our universe.

By that argument, all research is a waste of money, since it is all based on a small part of our universe.

[ydoaPs]

no, physical laws are the same in every part of the universe. that is an axiom on which almost all physical theories are based. what I am saying is that you cannot tell the size/shape of the universe when you have no clue how much of it you can actually see. we can only see so far. if that is the entire universe, the we must be the center, and i doubt that we are.

[Sayonara³]

yourdadonapogos said:

no, physical laws are the same in every part of the universe.

Aren't we forgetting something?

[ydoaPs]

how does that mean we can tell how big/what shape the universe is?

[Mad Mardigan]

yourdadonapogos said:

no, physical laws are the same in every part of the universe.

So could the speed of light be different? If the speed of light was to be differ, then there could be systems farther away, but ther light is half the speed so it has not reached out system yet.

[ydoaPs]

did you not read the quote you used?

[AL]

Edisonian said:

Everything ends somewhere.

That's a rather shaky premise. Can you prove that? It may be weakly empirically true, but it certainly isn't a priori conclusive.

[YT2095]

surely the entire arg depends upon What you define as "Space".
if by space you mean an area sparsely occupied with mater in which there will be a measurable distance between objects, then yes the Universe under these definitions has a Border so to speak. if include in your deffinition the area that this Universe is expanding into as "Space" also, then there`s no reason for it to have ANY limit at all :)

[Sayonara³]

yourdadonapogos said:

how does that mean we can tell how big/what shape the universe is?

What?

That vaguely-related question of your own is not a reply to the question I asked you.

[Severian]

yourdadonapogos said:

no, physical laws are the same in every part of the universe. that is an axiom on which almost all physical theories are based. what I am saying is that you cannot tell the size/shape of the universe when you have no clue how much of it you can actually see. we can only see so far. if that is the entire universe, the we must be the center, and i doubt that we are.

There is no centre of the universe. Why would there be?

The only assumption which goes into the astrophysical experiments is that we are not in an exceptional part of the universe. That all the other bits of the universe that we can't see (because they are outside our lightcone) are much the same as the stuff we can see. This is completely akin to the assumption that the parts of the universe that we cannot see have the same physical laws as the bits we do see - an assumption which you seem happy with. So why do you have a problem with one assumtion but not the other?