40 Billion

Originally posted by Dasa
It is impossible to measure the size of the universe unless you know where the edge of the universe stops.

So in your mind, the universe is like being inside a giant christmas tree ornament, a large sphere with us inside. So when you get to the outer skin, you can open a door and Presto!, you are out of our universe? Is that how you think of it?

Originally posted by twhitehead
Can you give me at least one reference?

No, sorry, talking about informal discussions and conversations, not really any records to refer to.

Originally posted by googlefudge
No, sorry, talking about informal discussions and conversations, not really any records to refer to.

OK. I still think it doesn't make any sense to refer only to the visible universe as 'the universe' even in an informal setting and even when the meaning is understood. But then again, physicists aren't always sensible.

Originally posted by twhitehead
OK. I still think it doesn't make any sense to refer only to the visible universe as 'the universe' even in an informal setting and even when the meaning is understood. But then again, physicists aren't always sensible.

Physicists don't like to talk about metaphysics.

Originally posted by twhitehead
OK. I still think it doesn't make any sense to refer only to the visible universe as 'the universe' even in an informal setting and even when the meaning is understood. But then again, physicists aren't always sensible.

As I say it's simply lazy use of language, in the same way that people often use theory instead of hypothesis.

Originally posted by twhitehead
Can you give me at least one reference?

Without having a dog in this show, I suggest:

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

Originally posted by KazetNagorra
Physicists don't like to talk about metaphysics.

LOL 🙂

Originally posted by JS357
Without having a dog in this show, I suggest:

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

ah, he was asking If I had a reference to a claim I made that didn't really have to do with the main point of the thread.

Originally posted by KazetNagorra
Physicists don't like to talk about metaphysics.

I am not talking about metaphysics either.

From Wikipedia:

In the future the light from distant galaxies will have had more time to travel, so some regions not currently observable will become observable in the future.

I reject any claim that tomorrows observable universe is metaphysics.

Originally posted by twhitehead
I am not talking about metaphysics either.

From Wikipedia:

In the future the light from distant galaxies will have had more time to travel, so some regions not currently observable will become observable in the future.

I reject any claim that tomorrows observable universe is metaphysics.

How could you go from the idea of photons taking the slightly curved path from galaxies on the edge of the observable universe becoming visible to the idea that would be somehow equated with metaphysics anyway? It's just a beam of light, right? Nothing more nothing less.

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

This was not some far away event in time 50 million years ago, this was here and now within modern times. Automobiles were being driven in cities lit up by electricity with people communicating by telephone and airplanes being flown.

Originally posted by sonhouse
How could you go from the idea of photons taking the slightly curved path from galaxies on the edge of the observable universe becoming visible to the idea that would be somehow equated with metaphysics anyway? It's just a beam of light, right? Nothing more nothing less.

Exactly.

http://en.wikipedia.org/wiki/Metaphysics
Interesting. I didn't even know that "metaphysics" had a definition other than "The supernatural"
http://en.wikipedia.org/wiki/Metaphysics_(supernatural)

Originally posted by twhitehead
Exactly.

[b]http://en.wikipedia.org/wiki/Metaphysics
Interesting. I didn't even know that "metaphysics" had a definition other than "The supernatural"
http://en.wikipedia.org/wiki/Metaphysics_(supernatural)[/b]

BTW, the last part of my last post was meant for another thread, misplaced it! I was talking to Robbie Carrobie about the space program. Bit of an oops.