The Cosmic Mind-Boggling Thread

[MacNimon]

Due to a couple of my workmates watching the new BBC series ‘Wonders Of The Solar System’ on Sunday, conversation at work took a slightly different slant from the usual topics such as football, etc. What started off simply as a ‘did you see…?’ conversation soon got more in-depth and started heading off in what seemed to be pretty mind-boggling directions for one person in particular, who previously had only thought of “stars being in the sky…they’re there, I hadn’t given it any more thought!”

So here’s a thread to discuss all those hard to understand concepts from the topic of space and cosmology. Not necessarily ‘hard to understand’ as such, but perhaps more like trying to grasp a concept simply because of the sheer scale and scope of the universe.

It was easy enough trying to explain the distances between planets, stars and then galaxies. But once we got to the topic of ‘what’s beyond the farthest galaxies?’ things started to get hazier. Obviously I don’t know what’s there! Is there actually anything there?! If it was at all possible to travel beyond the ‘edge of the universe’ for lack of a better phrase (and I know that’s not correct because the term ‘universe’ basically means everything!)…but if we could get beyond the confines of the Big Bang, what could we find?

And that’s not to mention the subject of time which also came up…before the Big Bang there was presumably no concept of the passage of time. No today, no tomorrow, no yesterday. But try explaining that to someone who hasn’t a clue what you’re talking about!

Which ideas like these do you have trouble trying to get your brain around?

[SiHart]

It's hard to comprehend just how big the universe is. I'm not really sure any human could get their head around that one- except maybe Douglas Adams who summed it up really quite nicely when he said "space is big. Really big..."

Si xx

[Stuart Wallis]

Douglas was always amazed at how the light used to get from the light switch to the eye - the process of the switch letting in the electricity; then the electricity jumping along the wires, heating the filament and making the incanescence leap out at you. It's something we take for granted, but when you consider that to get from the power station to you, how many atomic particles has the electricity had to arc across?

Something that puzzles me is, how does the diamond in the stylus in the record player needle help to convert what's on the record to what comes out of the speakers?

[WhiteCrowNZ]

It's a strange process we went through when we started to study Astronomy at University level.

I think before my degree, I used to think space was infinite. There's something funny about the word "infinite" because it's like a safety valve. I wonder who actually came up with the concept. But the mind does something strange with infinite - it never tries to acknowledge the number, it just accepts it's "really, really big".

First week of Astronomy though we learned in fact that the universe is not infinite and eternal. We learned how big it is, and how old it was.

The problem is - the numbers are so massive, any attempt to kind of mentally grasp the relative scale is doomed to failure - and so the numbers are kind of soul destroying. It can make you feel insignificant - like everything around you on a cosmic scale even fails to register. It's a kind of nihilistic feeling of void - which rather than Adams "really big" scene, he captures far better in the concept of the Total Perspective Vortex.

Certainly for all us first years, coming to terms with that sense of scale, was a kind of wierd experience. You'd see fellow student around the site, kind of wandering slightly dazed around. Although maybe that was more the effects of the Student Union bar over the philosophical impact of astronomy ...

[WhiteCrowNZ]

…before the Big Bang there was presumably no concept of the passage of time.

Actually wierd you should mention that - cos I was having a ponder about this myself this week ...

I have a kind of take sometimes on time, which some people don't like.

We all think we have a concept of what time is ... because we know what a second is, a day, a year.

But I don't really think time is directly measurable. We only really observe time because it's a way of measuring change.

For instance we use a quartz crystal in watches. We count out so many pulses and know that indicates so many seconds, but we're not measuring time directly.

We watch the sun rise, set and rise again, and that change to us equals one day.

It's impossible to imagine any concept of time, without also imagining some kind of change to go hand in hand. Time allows change to progress - and hence the only way to measure time is to measure change.

To me, if before the Universe there is nothing, then there is nothing to change, and hence time cannot be in any sense measured.

[Jon Masters]

As a certain Mr Hawkins says, time is dependent on entropy, and we only think of time going in the direction we have chosen because we expect entropy to increase.

I suppose in an unchanging universe time would have no meaning, but I wouldn't want to live there.

[MacNimon]

They say that the greater the distance we look into space, the further back we look in time. And that if we travelled out to the farthest galaxies, it would be like going back to the earliest days of the universe. But what would be find if we travelled out as far as was necessary to see what the universe was like before matter had congealed into galaxies etc? It would really only be like a ghost image because of how much things had stretched in the intervening billions of years.

And if was possible to get beyond the limits of the Big Bang, again what would we find? More of the nothingness from which we apparently sprung? It's actually hard to comprehend this nothingness when you think of our expanding universe in terms of a balloon being blown up! There must be something out beyond...!

My workmate was well out of his depth...he wondered what the nothingness would be like, "would it be dark?" he asked; my answer was how could it be dark if there wasn't anything there to be dark? And also the topic of time/absense of time came up, as well as the scale of the nothingness...it was everywhere and nowhere at the same time, simply because there wasn't anything to be anywhere at all!

I'm not trying to make the poor guy out to be daft or stupid, btw, or make a fool of him...he could put me to shame when it comes to his interests in wildlife and the likes...I've learned a lot from him there. But in this subject he was quite simply well and truly out of his depth! But it's not surprising, mind you...I understand logically much of what I'm saying but still when I think about it too much it feels as if my brain is going to explode!


These topics all came up in our conversation, along with the obvious one which nobody can answer...what caused the Big Bang when nothing existed to cause it in the first place?

Mind-boggling, indeed!

[Captain Tancredi]

I have a kind of take sometimes on time, which some people don't like.

We all think we have a concept of what time is ... because we know what a second is, a day, a year.

But I don't really think time is directly measurable. We only really observe time because it's a way of measuring change.

For instance we use a quartz crystal in watches. We count out so many pulses and know that indicates so many seconds, but we're not measuring time directly.

We watch the sun rise, set and rise again, and that change to us equals one day.

It's impossible to imagine any concept of time, without also imagining some kind of change to go hand in hand. Time allows change to progress - and hence the only way to measure time is to measure change.

It's an interesting thought- or to put it another way, if I lived in total isolation from the world, and my only way of measuring time was a watch which was running down so it lost a minute every day, at what stage if ever would I become aware that something was wrong?

[WhiteCrowNZ]

As a certain Mr Hawkins says, time is dependent on entropy, and we only think of time going in the direction we have chosen because we expect entropy to increase.

I like that. But who is Mr Hawkins? All I can think of now is some kind of International Talk Like A Pirate Day amongst physicists.

Supposedly Stephen Hawking has said though, "What came before the Big Bang?" is as meaningless as asking "What lies north of the North Pole?".

To an extent he's wrong to dismiss curiousity - because it's only human to say "what was X like before Y".

But he's on the ball as well. Everything we know was created in the Big Bang, so anything before that is completely unobservable, because we can only observe in the physical universe the aftermath from this event.

[Andrew Curnow]

Interesting thread, though totally out of my league. I'm very curious about this though, Mike:

First week of Astronomy though we learned in fact that the universe is not infinite and eternal. We learned how big it is, and how old it was

To me the obvious question from that is, if it's not infinite then what is outside it, and if it's not eternal, what was going on before it. I know they're almost philosophical questions rather than scientific ones, in that they make the mind boggle, but I'm intrigued as to what your tutors said.

[WhiteCrowNZ]

Hi Andrew

I'll just try and give you a rough idea of how it goes. Our Universe we 'believe' ... and in science 'believe' means most of our facts and theories fit this model ... is all the result of a start event we call the Big Bang.

Now Einstein has put a quite good case that the speed of light is an absolute - you cannot travel any faster than that speed.

So we often conside the edge of the Universe to be the speed of light multiplied by the age of the Universe. Bounded inside here is all the light and matter that was created by the Big Bang.

What is outside it we can't say. But we can say most likely it has no light and no matter because all these were a consequence of the big bang, so it has to be something else. Most likely nothing, but a kind of void without matter and without energy.

[MinaHarker]

Supposedly Stephen Hawking has said though, "What came before the Big Bang?" is as meaningless as asking "What lies north of the North Pole?".

To an extent he's wrong to dismiss curiousity - because it's only human to say "what was X like before Y".

I think it was an allegory, I highly doubt he was dismissing curiosity.

[MinaHarker]

To me the obvious question from that is, if it's not infinite then what is outside it

Nothing - it is all there is.

http://en.wikipedia.org/wiki/Universe

Cool, huh?

[Captain Tancredi]

Nothing - it is all there is.

http://en.wikipedia.org/wiki/Universe

Cool, huh?

About as cool as it's possible to get, if GCSE Physics serves me correctly. But that Wikipedia article really ought to have Peter Jones reading it.

[Andrew Curnow]

Just what I thought Ian! I particularly liked this little bit at the end of the opening intro:

It is uncertain whether the size of the Universe is finite or infinite

Interesting article though, even if it's frying my brain.

[MacNimon]

If the Universe is infinite, we'll certainly never find out! But it's got to be possible that once you get past the edge of our universe (ie past anything created by the Big Bang), there will be a void like Mike mentions above. But that void could also be like the void between galaxies, but on a gigantic scale, filled with a multitude of universes. And again, beyond that on an even larger scale, something similar once again...

I'm not sure if that' the 'Bubble Universe' theory or not, to tell the truth...

I haven't had a chance to read that article yet, but it sure looks interesting. Thanks for the link, Emma!

[Stuart Wallis]

There was a chapter or two on this sort of thing in The Science Of Doctor Who, which might at least still be available in a local library, and which tries to explain it in plain language.

2000AD had a story back in nineteen hundred and frozen-to-death where a spaceship reached the edge of the universe and found it to be a brick wall with graffiti on it; and another whereby another ship found that it was the film on a drop of water being examined by a group of students in a classroom. Fleas on the backs of an infinite number of fleas...