space never ends?

[Capricorn]

Just to jump in but I don't think anyone has thought that the earth was flat for a few thousand years.

The idea that people "thought" the world was flat is a recent idea, I have a feeling it was a Victorian idea - they are responsible for quite a lot of inaccuracies oddly enough. As I recall the Greeks had already made a pretty accurate calculation of the earths diameter 2-3000 years ago. I would suspect that the Chinese had done similar earlier still.

When it is said that people in the middle ages thought they would sail off the edge of the world is utterly innacurate. They knew why a ship disappears as it sails "over" the horizon.

Look at old medieval ocean/world maps, they are circular, not square or rectangular and the reason is that they understood that the world was round.

To the question of Space never ends? What's wrong with infinity? As BrianB says there are many infinities, this is just another.

[Aldebaran5]

There is a good article in the January issue of 'Astronomy Now' Explaining the why's and wherefore's of the universe. Explaining all about distances masses and whats out there. A good read.

Keith.

[yesyes]

Oh yes, that reminds me... I wanted to read that again and see if I get it this time ..

[wulfrunian]

Indeed - but as my sig suggests, we are somewhere caught in the middle of our understanding.

We have spent billions if not trillions (probably the true cost) building a machine to prove a particle we suspect exists - for what purpose ?

When we could have funded a programme of manned deep space missions... the technology is there and there are people willing to go into space...and take a good gander

The LHC isn't just there to try and find the Higgs boson. It's been built to attempt to recreate the conditions shortly after the big bang - in other words, to test out our current theories against observable evidence. I agree that manned space missions would be great, but we're not going to get nearly as much science from pottering around our Solar System.

[Rogue Leader]

Over my lifetime I have often pondered these very questions, usually only resulting in a headache.

Along this thought, has anyone (by anyone I mean a real scientist with more MB memory and processing power than I) considered that we may, on someone elses scale be living on some subatomic particle or similar? That is, in a similar way to what we believe to be an electron, someone else could see our sun as their electron in their model? Therefore our galaxy is just an atom?

Yes the writers of 2000 AD considered this back in the 70s when I was a boy.

A bloke in a spaceship had been in suspended animation for 10s of thousands of years while his ship tried to cross the universe. He wakes up sees he is still travelling and says something like well thats it there can be no end to the universe.

Rest of page frames pull out revelaing the ship is crossing a small sample of universe on a glass slide on a microscope with a big alien looking into microscope.

[LukeSkywatcher]

The human brain as amazing as it is can not even start to comprehend the vastness of space. I mean seriously.........what the hell is infinite?.

It would be amazing if we could image further then the furthest objects known........past the 13.7 billion yrs of the known universe. Is it just blackness?. The black vacuum of space was created with the big bang, so ahead of the furthest reaches of the universe can there even be the vacuum of space?

A person could go insane thinking about it.....except for a genius........who is already insane.

[yesyes]

There are things beyond the border of our observable universe. But light hasn't had the time to reach us yet from that far away.

That would mean that every day the observable universe gets a little bigger.

However, what I don't get is this:

I see that light will take 13.7 billion years to travel 13.7 billion light years. But when this light started travelling 13.7 years ago, the universe was tiny(-ish). So how can there be a distance greater than the time it takes light to cross this distance. Unless the universe was expanding at a speed greater than the speed of light at some point. In that case some parts of the universe will be forever hidden from our view.

[LukeSkywatcher]

There are things beyond the border of our observable universe. But light hasn't had the time to reach us yet from that far away.

That would mean that every day the observable universe gets a little bigger.

Of course. Silly me. Light has not reached there yet so we can not observe it. So we will only ever see the oldest/most distant objects known to us right now..........except they will be a bit older and further away.

We will NEVER see infront of them.

That makes sense.

Thanks for pointing that out.

P.S.~~~How fast is the known universe expanding?.................the speed of light?

Ehhhhhhh damn i just asked a STOOPID question. Its not like the universe can travel faster then the seed of light.

That stoopid question will self destruct in ..............5..............4............3....................2...............

[wulfrunian]

Space can expand as fast as it likes. It's not objects in space that move fast at light speed, it's space itself expanding. It's thought that space did indeed expand faster than light speed, much faster during the period of inflation.

[Space Bat]

Time itself is moving faster than light?

What if light isn't actually shifting (redshift) due to speed differences between the observer and object but more that there is a time difference.

The universe if it were to expand must expand at the same rate as time - it can not accelerate beyond time - as it wouldn't actually exist.

But what if the universe isn't actually expanding at all - just time is expanding and the things we believe are accelerating faster away or approaching is actually the differences in time between the observer and object?

If giving this process more thought why can black holes exist?

as such an object would actually not disappear as a black hole - but more that time itself has disappeared, or displaced, so the object doesn't get seen by the observers line of sight in time. ( so the star that makes a black hole is there where you think it is - just not there in the time you think it is )

Chris

[yesyes]

now you lost me...