Is space something or nothing?

[geeteenodubya]

One can derive a solution for the properties of "empty space," but does it make sense? Is there any reason to assume a geometry must exist -- that there cannot be two entirely unrelated things or worlds? If there is no pre-existing relationship defined by some geometry, then two things must either be adjacent or overlapping throughout their existence if they are to interact causally at any point. It seems to me that quantum mechanics has shown that the contents of our spacetime might define our spacetime itself, not just its shape and metric.

[Tormod]

Warm welcomes, geetee-w.

Which two "things" or "worlds" are you talking about?

If I have an apple and a banana and do not define a relationship between them, does that mean they must be either adjacent or overlapping?

I guess not - so I must be missing the point. But I guess there is a meaning to the term "pre-existing". Are you suggesting that spacetime was created for a purpose?

[Freethinker]

Hi GToW. Glad to have new voices.

Originally posted by: geeteenodubya
One can derive a solution for the properties of "empty space," but does it make sense?

Not quite sure what you are specifically referring to as "empty space,". The fluctuating quantum vacuum? intervals between dimensional manifolds?

Is there any reason to assume a geometry must exist --

Only if we don't want to argue to absurdity. We could start with the assumption that nothing actually exists and go from there.

that there cannot be two entirely unrelated things or worlds?

I am not aware of any such limitation. In fact in multi-verse two is a small number!

If there is no pre-existing relationship defined by some geometry, then two things must either be adjacent or overlapping throughout their existence if they are to interact causally at any point.

Or a non-destructive boolean "and" which does not have to exist across the entirety of both timespaces'.

It seems to me that quantum mechanics has shown that the contents of our spacetime might define our spacetime itself, not just its shape and metric.

Yes, and?

[geeteenodubya]

"Empty space" typically means -- if I understand correctly -- a submanifold without content. It is a valid mathematical concept, but I'm curious whether it is part of reality. In particular, is it obvious that a region of "empty space" might be embedded within our spacetime metric?

My interpretation of a "relationship" between two things was geometrical. They are related if there is a path from one to the other. I think that is equivalent to saying they might be causally connected. I suppose there are comparisons that could be made between things that are not related in this way.

[Freethinker]

Originally posted by: geeteenodubya
"Empty space" typically means -- if I understand correctly -- a submanifold without content. It is a valid mathematical concept,

I thought that might be what you meant, but never know till I ask.

but I'm curious whether it is part of reality. In particular, is it obvious that a region of "empty space" might be embedded within our spacetime metric?

As to it's part of reality, I guess we are still trying to figure out if the math it is a valid concept in, is valid? What's in between the intersections of at which other dimensions fold in on themselves? Untill we know whether this thought experiment preforms it doesn't matter? :-)

After we have developed a succesful TOE, we need a TON.

My interpretation of a "relationship" between two things was geometrical. They are related if there is a path from one to the other. I think that is equivalent to saying they might be causally connected.

Yes semantices. Are you math oriented? It would seem rather than pilosophically oriented.

[lindagarrette]

Trying to define space opens up a box of other issues. what is content? what is matter? Are they all just mathematical constructs? At the string theory level, for instance, there is no such thing as a particle. Also, at that level, there is no place in the universe that has no content. Or if there is, where is it. Only when there was nothing, like before the BB, was there no content. Right?

[Freethinker]

Originally posted by: lindagarrette
Only when there was nothing, like before the BB, was there no content. Right?

This is where we have to be very careful. We can not say that there was nothing before the BB.

The BB is an event to which we can track back to what we understand to be the start of our current physical existence. "Before that?" may not be a valid question. Perhaps anything "thing" that existed before that would not follow what we understand as the laws of physics as they currently exist.

[geeteenodubya]

I believe my question could be rephrased in terms of the "intervals between dimensional manifolds." However, my impression is that "interval" and "between" have no meaning in that context. The first question is whether the absence of a dimensional manifold is a meaningful concept, since no point can be located in it.

The second question is whether a real dimensional manifold can have no content. Would its shape be defined?

[paultrr]

Basically, everything we have as far as theory goes for the particle scale on down is a construct.

[DaDaLiCh]

There is only one thing which I need to state:

How could the the BB have happened, how could living being just spontaneosly be created or formed, even through evolution, without a divine being at the helm. I see this as impossible. God MUST have existed for the universe to be created with such precision. (Please excuse my english, it's my fourth language and i'm not very fluent yet)