Universe boundary

[ronthepon]

The universe is said to have a boundary in some... sources. I'm thinking that:-

 

1: What is at the edge of the boundary? How is this boundary defined?

2: Is there such an edge?

3: What is beyond the edge?

4: Is the universe bounded in size in 3D the way our planet is bounded in 2D?

 

Here are my thoughts:

1: The first group of photons that were emmitted and were moving absolutely away from the centre of the big bang(If the big bang was symmetric in any way)

 

2: B)

 

3: Empty space, absolutely empty, not having any energy or any particle at all

 

4: A lovely thought and possibility.B)

[UncleAl]

All 4(pi) steradians of direction point exactly at the Big Bang. No boundary.

 

If the vacuum were empty you would exactly know its contained energy over time - zero. That violates Heisenberg Uncertainty. It can be trivially demonstrated that the vacuum contains zero point fluctuations - Casimir effect, Lamb shift, Rabi vacuum oscillations, electron anomalous g-factor... 1/2 virtual photon per allowed electromagnetic mode.

[ronthepon]

If the vacuum were empty you would exactly know its contained energy over time - zero. That violates Heisenberg Uncertainty.

 

I thought that the uncertainity principle had implications only for our observing power, not how the particle etc is. Please let me be corrected in a explinative manner.

 

What are virtual photons?

[InfiniteNow]

I thought that the uncertainity principle had implications only for our observing power, not how the particle etc

is

. Please let me be corrected in a explinative manner.

 

What are virtual photons?

Hi RTP,

 

Uncertainty principle has implications on all of reality, not just the observation of that reality. It is very much at the heart of all Quantum Mechanics, which has repeatedly been demonstrated to be the (currently) best approximation of everything in the universe.

 

As for virtual photons, it's really easy to Google. Here's a link with some FAQs that you might find useful/educational. Enjoy!

 

http://math.ucr.edu/home/baez/physics/Quantum/virtual_particles.html

 

 

Cheers. :cup:

[ronthepon]

Thanks a lot for the link

[Farsight]

The concept I've got in my head is that the Universe is a hypersphere, and a black hole. You keep going thataway and you end up coming back thisaway.

[Shekhar]

Universe should be 3D and there may be many universe(s) perhaps having different rules of Physics........and there is infinetely empty region (space)

[Jay-qu]

Universe is obviously 3D and there may be many universe(s) perhaps having different rules of Physics........and there is infinetely empty region (space)

And obviously these are all theories, unless you can support these claims of course..

[Farsight]

Universe should be 3D and there may be many universe(s) perhaps having different rules of Physics........and there is infinetely empty region (space)

You can't have many Universes, by definition. Universe is derived from the Greek.

Uni means "one", as in unicycle. And versa, means "turned into", as in vice versa. So Universe means turned into one, which really means "everything". And you can't have more than one everything.

[Zythryn]

You can't have many Universes, by definition. Universe is derived from the Greek.

Uni means "one", as in unicycle. And versa, means "turned into", as in vice versa. So Universe means turned into one, which really means "everything". And you can't have more than one everything.

 

I believe there are a number of hypothesis regarding multiple universes.

While the literal definition may imply there can't be, definitions are known to change. Isn't one theory called 'M-space' or something like that?

[TheFaithfulStone]

That's kind of a semantic argument there. No, you cannot have more than one everything, but it's tough to say "multiple EXTREMELY large unbounded spatial area governed by a particular set of physics, and sharing a common timeline at all possible quantum junctures."

 

So we shorten that last bit with "universe"

 

TFS