What proof?

andrewkirk

Topologically speaking, every point of our spacetime (I won't call it a universe because 'universe' to me means 'everything there is', which would include whatever our spacetime is embedded in) would be a boundary point under the subspace topology if it were embedded in a higher-dimensional space, in the same way that every point of the line y=0 is a boundary of that line considered as a subset of the two-dimensional number plane.

If our spacetime were embedded in a 7-dimensional space (5 dimensions may not be enough to host an embedding of our spacetime) and we could somehow propel ourselves in a direction that is perpendicular to all three of our spatial directions and to our time direction (think of an ant jumping up off the balloon in the analogy) we would immediately be 'out of' our spacetime as soon as we had travelled the tiniest distance in that direction.

You must bear in mind though that these are all just mathematical possibilities. There is no scientific evidence for or against them and they bear no relation to our current scientific theories and observations. (hence this thread would fit better under mathematics or philosophy than here in cosmology).

DeepSpace9

Okay thanks guys, I think all my questions have been answered.

Mark M

Not in the sense your thinking about. It could be spatially separated (via the extra dimensions) from other regions of the universe. But it isn't as if there is some kind of boundary separating them.

phinds

Ridiculous. You obviously do not understand the balloon analogy. Do you even understand the word "analogy"? Try this:

www.phinds.com/balloonanalogy

DeepSpace9

I do understand balloon analogy and yes I know what analogy means.

My questions were answered as I stated in post #19 and I now understand that there our no boundaries.