Where does space end..

xelasnave · #1 15-11-2008, 06:22 PM

No I am not talking about the edge of the Universe stuff this is more close to home...

We all know we have the Earth and we have space..but where does space end..10 miles above the Earths surface..20 even... so if sapce is expanding why dont we expand..I would have thought space extended to the smallest regions of matter... the room between atoms in molecules..is that not space? so why does this space not expand..or does it expand...

Could it be that all of us are expanding..we would not know because everything would be expanding at once... I must say I do feel biigger than when I was 7 years old.. is that evidence?

So the space that is expanding..where does it end.. and why doesnt matter expand with it... in accordance with that balance seeking thing.

alex

jungle11 (Greg) · #2 15-11-2008, 07:06 PM

I think Hubble's constant is supposed to be a measure of expansion, but i think that is measured so that an object x amount of megaparsecs away is moving away from us at 72km/s (or something like that)

Thats a pretty small measurement considering a megaparsec from earth is further than Andromeda. (3.3 million L/yrs?)

On a human scale, i'd guess the measurement would take trillions of years to have an effect (which of course is totally off the human scale!)

Perhaps expansion only works on space itself, not objects contained within localized gravity fields (planets, stars, galaxies ect)

I read a description of it awhile ago in which you but some raisins in a dough (to make bread, sorry im male, had to say that

) the raisins are galaxies, the dough -intergalactic space. As the dough expands in the oven, the raisins remain in the same position realative to each other.

Phew...Ill shut up now

sjastro · #3 15-11-2008, 07:12 PM

The answer is the same to the "edge of the Universe" thread.
Space does not expand. Space-time does.

Regards

Steven

jungle11 (Greg) · #4 15-11-2008, 07:17 PM

So (speed of light nonwithstanding) if we positioned a probe a megaparcec away, and could communicate with it in real time, would that probe be moving away from us or sitting still?

TrevorW · #5 15-11-2008, 07:21 PM

Ah!! more to the point where does its start ???

mick pinner · #6 15-11-2008, 07:22 PM

things within a space can expand, space itself cannot.

xelasnave · #7 15-11-2008, 07:30 PM

Quote:

Originally Posted by mick pinner

things within a space can expand, space itself cannot.

or the other way around Mick???

alex

Jen · #8 15-11-2008, 07:30 PM

Quote:

Originally Posted by TrevorW

Ah!! more to the point where does its start ???

ouch my head hurts

xelasnave · #9 15-11-2008, 07:32 PM

and when they issolate the HB whats it made of??? and is there any space between its parts?
alex

jungle11 (Greg) · #10 15-11-2008, 07:37 PM

Maybe string theory is the go, space, matter, all of it is strings viabrating at different frequencies. So where does space end? Maybe it is essentially the same as matter, only singing a different tune!

xelasnave · #11 15-11-2008, 08:02 PM

Quote:

Originally Posted by jungle11

Maybe string theory is the go, space, matter, all of it is strings viabrating at different frequencies. So where does space end? Maybe it is essentially the same as matter, only singing a different tune!

String theory..string idea if you please... what does string theory say???

I mean we feel warm and fuzzie when we hear about ti and it sounds neat..but unless I am mistaken it is more geometry setting out limits of movement ..simply put..

and maybe I missed the point but Mr Suskin comes across as a fella seeking to be the next great man DrA ...

I dont but it and I dont buy super symetry or multiple dimentions(other than smaller degrees of a scale...) and multiple universes... no gravity does not become a weak force by leaking some of its energy into another dimention and it will not be posibble for us to communicate with beings in another dimention by learning to control a gravity wave..which I sound note has not yet been found.. I think because this stuff seems hard to understand no one questions the reasonableness of some of these ideas..sadly I demand very simple and believable theories... like mine of course

..opps sorry its an idea

...

Still I am happy to be convinced string theory holds merit...but there are no experiments..and they say they have gravity wired..well so do I

but as I dont have experiements I will be humble and call the notion an idea

..

alex

xelasnave · #12 15-11-2008, 08:05 PM

He (Suskin)rehashed a 200 year old formula so I believe ...hardley original...30 years old and not going anywhere... maybe it will get a leg up at cern but what does it say... when the warm fuzzie feeling has gone..what does it say.

alex

jungle11 (Greg) · #13 15-11-2008, 08:11 PM

Quote:

Originally Posted by xelasnave

I think because this stuff seems hard to understand no one questions the reasonableness of some of these ideas..sadly I demand very simple and believable theories... like mine of course

..opps sorry its an idea

...

Yep, it is only an idea, and we may never be able to see things on such a small scale to prove it but then again, two thousand years ago the Earth being a sphere wouldn't have seemed a simple and believable theory.

xelasnave · #14 15-11-2008, 08:20 PM

I just get ticked off that String Theory is called such when there is no support as I understand of observation and experiment my point is it is still an idea or hypothisis... but its not going anywheres I feel...

alex..

jungle11 (Greg) · #15 15-11-2008, 08:27 PM

chasing ghosts...

Zuts · #16 15-11-2008, 08:43 PM

Hi,

Space time only has to expand a little bit say a fraction of a fraction of a fraction of a percent per centimeter say per year. However there are a hell of a lot of centimeters between here and the edge of the visible universe. This adds up to a hell of a lot of new space per year.

So locally you cant see it expanding on any human scale and in any case the strong nuclear force and gravity would overcome any expansion locally. However non-locally on the scale of the visible universe the expansion is readily mesureable and visible.

Cheers
Paul

KenGee (Kenith Gee) · #17 15-11-2008, 08:44 PM

All of space time is expanding, objects within space are all affected by this. However the "pressure" of the expansion at small scales is nowhere near the forces holding things together. Go back to the idea of a balloon being blow up to explain space-time expanding. Now if you put those sticky paper dots about 1cm across on it to represent the galaxies. Now what you see is the distance between each galaxy increasing , but the galaxy it’s self is not getting bigger.
So we are not all flying apart, but on the biggest scales this expansion becomes evident. the really weird thing is it seems to be speeding up!!

jungle11 (Greg) · #18 15-11-2008, 10:03 PM

Hey ther Paul and Ken

I agree with you both. It was what i was trying to say, but clearer!

gman (Grant) · #19 15-11-2008, 10:15 PM

What I would like to know is which galaxies etc are moving in the same direction as us and which are moving away and in what direction.

Also is our movement in the universe due solely to the big bang or a combination of the big bang and the expanding universe.

People say the expansion is speeding up.

If the expansion was solely due to the big bang, wouldn't maximum velocity have been reached immeadiatley afterwards and there afterwards the slow down starts?

xelasnave · #20 15-11-2008, 10:40 PM

Quote:

Originally Posted by gman

What I would like to know is which galaxies etc are moving in the same direction as us and which are moving away and in what direction.

You call them out I will call out where they are going

Also is our movement in the universe due solely to the big bang or a combination of the big bang and the expanding universe.
Yes

People say the expansion is speeding up.
People will say anything

If the expansion was solely due to the big bang, wouldn't maximum velocity have been reached immeadiatley afterwards and there afterwards the slow down starts?

I dont know but that seems reasonable

. I think the Theory of Inflation has space expanding most rapidly indeed but after that it must have slowed down.. and then started expanding again and now we notice that it is expanding more rapidly than before..not not as rapidly as during inflation...

Observation suggests expansion is speeding up ..there seems to be a lot of research into dark energy and one of the first things they seek to do is to measure the expansion using supernova standard candels so they are able to gauge the rate and more importantly the rate at varies times.. however it certainly seems expansion is accelerating and dark energy is getting the blame...

alex