What constitutes space?

Question

What constitutes space?

Answer 1

It is not really very well defined, due to the gradual thining of the atmosphere,  but NASA will award a person astronaut status if they reach an altitude of 50 miles ( about 80km)

Answer 2

If you place two chairs back-to-back then separate them you have created 'space' between them.  The space between two stars can approach a pure vacuum (with photons passing through it).  Outer space (near earth) is generally considered to be the space above earth's atmosphere.

Answer 3

dunno soz

xxxx

Answer 4

Space isn't something that exists unto itself, it's defined by things that exist rather than the other way around.

One of the greatest achievements of Einstein, following in the footsteps of Ernst Mach et al, was to remove the concept of space as this "background" on which everything else moves. It's easy to think of space as a grid, such as the cartesian grid from high school math classes, such that we might assign coordinates to everything with (x,y,z). However, there is no (0,0,0) -- no center, no privileged reference frame.

The best way to describe what Einstein accomplished in revolutionizing our understanding of space and time is to compare it to a sentence. Spacetime is like a sentence in that a "sentence" doesn't have an existence unto itself, it only exists in the sense that it is a structure defined by the words in it. In this case matter is analogous to the words, whereas space is analogous to the sentence.

Space wouldn't exist if nothing else existed just like a sentence couldn't exist without words to define it. Likewise, space couldn't exist if only one object existed just like there's no such thing as a true one-word sentence.

There is a lot more to say but I think the sentence analogy will have to do in the limited space of Yahoo Answers for brevity, but I would welcome any email at [e-mail] for more discussions on the ontology of spacetime.

Answer 5

According to my Fractal Foam Model of Universes, space is measured in median-size ether-foam bubbles. A meter is about 10^35 median-size bubble widths; that does not change as space expands.

Our ether foam is the cosmic foam of our sub-universe. As sub-universe space expands (in backwards time) its cosmic-foam bubbles pop, which means that our ether-foam bubbles un-pop. When an ether-foam bubble un-pops, one bubble becomes two bubbles, and approximately 10^-105 cubic meter of new space is added to our universe. So the expansion of sub-universe space drives the expansion of our space, which in turn drives the expansion of super-universe space; the sequence is infinite.

Also, space has an equivalent in dark energy. When a sub-universe cosmic-foam bubble pops, dark-energy pressure waves radiate thru the cosmic foam of the sub-universe, which is our ether foam. Due to time inversion, those p-waves in our ether foam converge and "cause" an ether-foam bubble to un-pop. (It's a bit tricky to distinguish between cause and effect, here.) So a certain quantity of dark energy is converted to new space. E = mc^2 with m = volume times an unknown constant times the unknown inertial density of the ether.

Answer 6

if i can move me hand through it