# Thread: The Age and Size of the Universe.

1. ## The Age and Size of the Universe.

Hi there,

I was watching a TV program yesterday called "Beyond the Bigbang". A
statement was made in the program that the universe was about 13.7
billion years old and that the known universe was something over 150
billion lightyears across.

Now, assuming that the universe is expanding equally in all
directions, how do you get from the point of origin of the big bang
out to a distance of more than 75 billion lightyears in only 13.7
billion years?

This stuff really confuses the hell out of me. :-)

Bye for now.
Bye for now,

George Dingwall

Invergordon, Scotland

http://www.georgedingwall.co.uk

2. ## The Age and Size of the Universe.

George Dingwall wrote:

There is no point of origin. (Or, all points are equally original)
Not that this answer will make it less confusing...

I'd guess that Life, the Universe and Everything is equally confusing for
all who live here

3. ## The Age and Size of the Universe.

On Sun, 04 Nov 2007 13:48:43 +0100, Iordani <somewhere@earth.net>
wrote:

If the Universe wasn't confusing very few people would study it.
Fortunately it gets more confusing with more study.

Steve

--
Neural Planner Software Ltd

http://www.easynn.com
http://www.tropheus.demon.co.uk

4. ## The Age and Size of the Universe.

On Sun, 04 Nov 2007 13:48:43 +0100, Iordani <somewhere@earth.net>
wrote:

If the origin was the bigbang when all energy and matter in the
universe occupying a volume of less than the smallest sub-atomic
particle, it either had a finite size or no size at all.

So my question is this. If they now know that it has a volume which is
150+ billion light years across, then it must have occupied a smaller
volume in the past. So how did it manage to expand from virtually
nothing to 150+ billion lightyears across in only 13.7 billion years.

Surely anything that existed shortly after the bigbang could not now
be more than 70 billion lightyears away from its original position.

Bye for now,

George Dingwall

Invergordon, Scotland

http://www.georgedingwall.co.uk

5. ## The Age and Size of the Universe.

"George Dingwall" <george.gdingwall@virgin.net> wrote in message
news:m2pri3dqsph48lrdvvbrdm7eern6df4lkr@4ax.com...

Well it no doubt had a size when space-time formed at that moment.

The radius for the visible universe is 13.7 (well minus about 300,000 years
for the cosmic microwave background). When people talk of the size of the
universe typically they refer to the visible, or known universe.

Figures bigger than that, are as far as I know estimates based on things
like inflation, the microwave background etc.

Sure, but relative to what? Maybe it is in more or less its original
position, its position relative to something else in the universe could
quite easily be 70 billion light years distant. Space-time itself is not
bound by the speed of light, during inflation the universe expanded much
faster than the speed of light.

At the moment the universe is expanding at about 70 km/s per megaparsec.
Therefore if there's something (at this moment in time, today, and we wait
say 10 or 15 billion years for the light to reach us) is say 4.5 gigaparsecs
away, it will appear to be moving away from us faster than the speed of
light. This isn't due to its own actual motion, just the expansion of the
space between us. However that light would be red shifted into oblivion
before it could reach us.

Does that make any sense?

--
Paul Smith,
Yeovil, UK.
http://www.dasmirnov.net/

*Replace nospam with smirnov to reply by e-mail*

6. ## The Age and Size of the Universe.

On Sun, 04 Nov 2007 15:34:42 GMT, George Dingwall wrote:

You're thinking of the speed of light as a limit and at creation time
it wasn't because the physical laws didn't exist until after the
creation bang. Is the first few tiny tiny bits of a second if expanded
at a fantastic rate to nearly the size it is now. Then the Universe
realised it existed and the physical laws came into effect and
expansion continued at a similar rate to today. At least that's my
understanding of what I read about it. I can't remember the title of
the book now but something like 'The Seven Ages of the Universe'.

The 13.7 billion light years that we can see are just the size of our
raisin that we are in the centre of somewhere in a giant Christmas pud
:-)

--
Regards - Rodney Pont
The from address exists but is mostly dumped,
please send any emails to the address below
e-mail ngpsm4 (at) infohitsystems (dot) ltd (dot) uk

7. ## The Age and Size of the Universe.

George Dingwall wrote:

I think it's wrong to see it as "occupying a volume"
At the time, this was the whole universe. There is nothing on
the "outside", not then and not now.

I also think "across" is a bad word to use for this. If you do, you will
end up like me and think like; I can see backwards in time by looking
out in all directions. The more powerful the telescope, the older the
universe I can observe. So it's all like a big onion with the oldest layer
being the outmost layer of the onion. And here I am in the middle, so
this is the newest part (and the point of origin...). And the part
biggest in volume is the oldest one. Hmmm... Clearly, this very "human"
way to view things must be the wrong approach when looking at the universe.

And no, I don't know of any right approaches, sorry. I'm only human

I wouldn't bet on that.

bang' 'superinflation' 'theory of relativity' etc..

Stephen Hawking's 'A Brief History of Time' is also good reading.

8. ## The Age and Size of the Universe.

In message <m2pri3dqsph48lrdvvbrdm7eern6df4lkr@4ax.com>, George Dingwall
<george.gdingwall@virgin.net> writes

The speed of light is a limit on the movement of (non-tachyonic) matter
in space; however the expansion of space, which is not a movement of
matter in space, is not limited by the speed of light. If you want to
know more I think you have to study General Relativity.

--
Stewart Robert Hinsley

9. ## The Age and Size of the Universe.

The real problem lies in presentation. Was it a presenter or an astronomer that
claimed the diameter of the universe was >150 billion LY? I suspect the
former..... Or perhaps the figure was mis-heard?

Either way, confusion is a part of understanding, here. Our concept of the
'diameter' is not a real distance anyway. Imagine being able to witness the
start: there are no dimensions that can be judged at that 'time'. Treat such
figures with curiosity rather than gospel.

L

On Sun, 04 Nov 2007 12:12:01 GMT, George Dingwall <george.gdingwall@virgin.net>
wrote:

10. ## The Age and Size of the Universe.

"George Dingwall" <george.gdingwall@virgin.net> wrote in message
news:gcdri3lqqempjg2lq2f6rpdbr1gnd7kfkr@4ax.com...

I wouldn't worry too much - it's worth remembering that these theories of
cosmology and the origins of the universe are just that, i.e. only theories.

It's not like in earlier simpler times when a scientist "discovered"
something like the cellular structure of plants under a microscope.

These sort of theories are constructs invented to explain and predict
observable phenomena. Whether they actually represent "reality" is a moot
point. Some would say it doesn't even matter, as long as we can calculate
the simple stuff like how to get a spaceship to Mars.

Where it breaks down is when we end up having to add terms in for things
like "dark matter", which may or not exist but represents the admission that
the mathematics don't work and we've had to fudge it somehow.

It's a bit like when as kids we used to get teachers explaining that atoms
are like miniature solar systems with electrons whizzing round the nucleus
in orbits like tiny planets. They're not, but it helped to form a mental
picture and put things into some sort of context. That's all we can hope
for, I suppose.

Page 1 of 2 12 Last

#### Posting Permissions

• You may not post new threads
• You may not post replies
• You may not post attachments
• You may not edit your posts
•