A couple of questions.....

[Teddy]

Hi all

The thing i like about astronomy is the things we talk about etc are so big and far that its hard to picture in our tiny (in mycase:eek:) heads. so as i am a thinker at times i thought i would ask some questions (for fun and knowledge)

1 - If our universe is expanding........what is it expanding into.

2 - If the answer to the above is nothing...... whats nothing and can nothing go on forever !!

3 - how far is earth from the centre of the universe.

4 - how far is earth from the edge of the universe.

and 5. Whats to say there is not lots of other universe's or something were not aware of on the other side of ours.

i love the thought that although to us our universe is soooo big , could it be soooooooo little to something else on the outside of it...(if possible)

as i am not a brainbox please dont take the p155 if u think these are silly questions. i just find the thought provoking aspect of them quite fun and challenging to my little brain !!

Cant wait to see any answers .........

Teddy

[Sam]

Good questions. The thing I find tricky getting my head around is that the whole lot all expanded from the big bang so everything is getting further away from everything else so there isn't really a centre - just a centre of what we can observe. mmmmm very thought provoking.

[Peter Drew]

If the Universe really is infinite, which it seems to be, then the centre of the Universe is wherever you happen to be, as it is your only practical frame of reference.

[Rusty Strings]

Anybody's brain hurting yet?

John

[Teddy]

yeah mine !!!

i love the thought of the universe is expanding and its poss infinate , but it hurts to work that out.

If its expanding then there must be a point where its expanding into something (or nothing) and if thats an edge then surely its not infinate. if we could travel faster than the speed of the expansion then could we travel out of the universe ???

arrrggghhh

also if the universe came about due to the big bang then could this have occured elsewhere . could two universe's( or more) be about and could they ever meet..mmmm

my head..........

[BrownClaw]

If you answer the question 'What is the universe expanding into?', then you also answer the question 'What was around before the Big Bang?'.

My own personal view is that for a 'thing' to exist (even empty space), it must have both area, and time. Mass isn't important; if an empty space can be physically measured, and is subject to a 'past, present and future', then it exists.

Before the Big Bang, nothing qualified those criteria. Only when the entire universe exploded outwards, did 'existance' rush into 'non-existance', bringing with it measurable space, and measurable time. Anything outside that area of expansion simply did not exist...

The same thing is happening now. The thing 'outside' the current universe is precisely 'nothing', until it is bought into the fold of the expanding universe of 'something'.

So, answer the questions 'How big is 'nothing'? Is 'nothing' infinite?' and you'll have your problem solved.

Or I may be talking complete rubbish

[Merlin66]

The best analogy I can give is think about a couple of ants crawling around the surface of a very large balloon which is being inflated.....

The ants could walk around forever - so the surface is infinite

The ants are moving away from each other due to the "expanding surface universe"

The orginal centre of the the "big inflation" was somewhere inside the balloon not a point on its surface.....

This 2 dimensional example, expanding into a 3D space is as about as simple as I can make it.... in real life we have a 4 (at least!)dimensional universe ( length, breadth, hight, time/ space) expanding into (at least!) a 5 dimensional.........

[acey]

Nice questions!

1 - If our universe is expanding........what is it expanding into.

Its "size" is measured by the distance between galaxies, which is increasing. It isn't expanding "into" anything.

2 - If the answer to the above is nothing...... whats nothing and can nothing go on forever !!

A classical vacuum. But the universe is not expanding into a classical vacuum.

3 - how far is earth from the centre of the universe.

There is no centre.

4 - how far is earth from the edge of the universe.

There is no edge.

5. Whats to say there is not lots of other universe's or something were not aware of on the other side of ours.

There are many theories like this: try doing a Wiki/Google search for many worlds, chaotic inflation, branes, multiverse. Or try these books:

Paul Davies, The Goldilocks Enigma

John Gribbin, in Search Of The Multiverse

Michio Kaku, Parallel Worlds

They're all good.

[Astro_Baby]

And dont forget the 'cosmeg' in that list

Who knows maybe its steady state and we only THINK its expanding.

[Catanonia]

Loads of good questions and I love to think about these types of things.

My personal favorite at the moment is 11 dimensions and what we are expanding into is just a rift between these dimensions. We only think of 4 dimensions (including time) but there are 7 more to play with all around us.

When you can get your head around this concept, then it isn't a large step to imagine other universes in between these dimensions such as our with differing physical laws.

Now these seperate galaxies will also collide, giving off BIG bangs all over the place and so giving an endless supply of universes all self generating in the soup of universes.

Also all these gamma ray bursts they think are distant hyper nova's in distance (at the edge of our universe) star nursuries. I personally think they are these other universes banging into each other and what we are actually witnessing is the gamma burst from other big bangs.

Another thought of mine is that perhaps, just perhaps the speed of light has actually changed continually throughout time by small amounts. If this is the case, then loads of other things are possible.

Now my head hurts too

[acey]

Also all these gamma ray bursts they think are distant hyper nova's in distance (at the edge of our universe) star nursuries. I personally think they are these other universes banging into each other and what we are actually witnessing is the gamma burst from other big bangs.

I understand it's the wrong gamma signature for that. Again, people have looked for galaxy-scale matter/antimatter collisions but the sort of gamma rays you'd get from that haven't been observed.

Another thought of mine is that perhaps, just perhaps the speed of light has actually changed continually throughout time by small amounts. If this is the case, then loads of other things are possible.

There's a book about that too:

Faster Than the Speed of Light: The Story of a Scientific Speculation: Amazon.co.uk: Joao Magueijo: Books

[omneferuss]

Ahhh.. the 'Big Questions'. That luxury, of idle cognitive processes turned to wonder and speculation, since first fire freed us from huddled fear.

We've come a long way. Even some in poorer countries now have the spare time to ponder it all.

But all of our advancements leave us, with all our acquired knowledge, no more than a dot at the end of a sentence, on a page in a book, in a vast library, in a megalopolis of libraries.

We thus far, can only perceive a few sentences afar, at best. Much less can we decypher the languages and contents of all the books.

We are very very tiny ants on that huge expanding balloon... and the scale goes the other way too !

The bigger side of things grabbed our attention first, predictably enough, but 'The Answers' need to account for the small too.

It took 5 or 10 millenia for us to get around to it, but think of the LHC as the direct descendant of Stonehenge... only inward not outward looking... that's where the 'eleven' (any more bids?) 'dimensions' lie.

Gazing and measuring outwards we see structure on structure.. something like a Mandelbrot pattern.. but also backwards in time, as infered by the finite speed of light... and can therefore, consider it as simultaneously looking ever deeper into the 'smaller'.. because of the 'expanding-universe' and 'Big Bang' theory.

We might consider our time-space dimension as the extrapolation of our own conscious awareness of things.. a Pythonesque Theory of the Brontosaurus, "which is mine and belongs to me"

..it starts infinitely small, gets much much bigger and then thin again at the other end !

....and then there's gravity... so weak that an ant can lift against it fifty times the ant's own weight, yet so strong that it reaches lightyears to twist and gyrate vast quantities of matter.

Indeed, gravity is largely the defining principle forming the shape of matter outside of the atomic realm... albeit, tweaked by the perturbations of thermodynamics and the flux of energies' evanescent eddies on course to ultimate entropy.

It really is a mighty tribute to our collective capacities that we have extended the means of our perceptions by the application of our means of conception.. generation after generation.. ideas inherited and mutated like genes... technologies expanding our powers and extending our reach. Too bad it looks like we've soiled the nest , perhaps fatally, before we could leave it.

Just as our eyesight has its limits so do our minds.

Look where we are going, but mind where we tread... what's beyond will always beckon but it's not where we are. The journey ahead is where our descendants, not us, will be.. from what we do now.

It's a Universe of expanding possibility.. evident in, and aped by our enquiring minds... evolved from 'nothing', not created fully formed and immutable... but not pure chaos, either.

There are patterns.. mathmatical shadows on our cave walls, cast by the firelight of our curiousity, but no Magic Pudding answers.

Call it '42', or something,and worship it if the unknown disturbs you.. fetishise it and propitiate it with ritual, if that makes you feel better.

That's what we've always done.

But thankfully we didn't stay at that. We've moved on... and travel broadens the mind ! The Earth is no longer flat and central to a fixed and finite Universe surrounded by God in His Heaven, like a coin in cottonwool. It's a drop in the ocean, an ocean where there's more space than water.. oceans of space.... but even in matter itself there's more space than matter!

And that 'space', inside matter, would be expanding too, if 'the four forces' were overcome by 'The Dark Energy'...... (where did I put my light-sabre?)

Yes.. all this science is like a giant box of wheatybrans.. lots to chew on and full of fibre that they tell me will do me good to digest..

but there's no plastic toy in the bottom of the box.

It's those luscious sultana-like spiral galaxies etc sprinkled through it that keep me sweet.. if not regular.. at this astrodalliance...

but thanks for the opportunity of getting some of this out of my system

[Teddy]

Nice one u lot.

I am glad i posted these questions as it makes for intresting reading. Although i have to say ......my head hurts !!!!

Glad people enjoy these types of discussions and it shows how much we know and also how little we know , which itself is a nice thought !!

I dont think we will ever truely find out what its all about , i do know i wont miss one second of my life and my family and freinds life coz its so special to me and its oh so short.

Being alive NOW is a gift. Past and future is cool but NOW is cooler !!!!