What is does space mean in astrophysics and how can space "bend"?

Matter occupies physical "space." Volume is a measure of the amount of space an object occupies. How could the fringes of the universe be expanding into non-space? How can one possibly explain the creation of space by the expansion of the universe? If matter can neither be created nor destroyed, how can space? If a spaceship were able to reach the outside of the universe and actually surpass it completely, venturing beyond the universe into "nothingness," what would happen? Would the spacecraft create more space due to its own gravity or would it simply occupy more space that was already there? Would it be destroyed or create some kind of logical paradox?|||Keep in mind here that not all physicists agree.





If general relativity is correct, then space is something like a stretchy fabric - get a trampoline and put a bowling ball in the center - that would be like the sun. If you just place something on the outside of the trampoline, it'll go towards the bowling ball - that would be gravity. Gravity, as defined by general relativity, is caused by the bending of space where a heavy object causes the fabric of space to bend. It explains why light bends around stars.





Now, all of this is a caveat, because we are trying to explain the universe from a single vantage point (Earth). There's no way to really know what's outside the "edge of the universe", because all we can see are the stars at the outer edge of what we know as our universe. There's no way for us to see what's beyond that - if there's anything out there, it's not emitting anything we can detect.|||The universe, in theory, has an infinite amount of space. There is a known amount of matter and energy believed to be expanding away from the a theoretical point of origin of the universe.





If a sapceship flies out beyond all known matter into the void of space, it is now the defining point of the outer most limits of known matter. Space itself contines onwards forever in all directions around it.





More commonly referred to is space-time. It represents 3D space with the time component, this allowing for the state of things to be considered over a period of time (i.e. in motion) Space-time is bent by all mass in the universe. The best way to think of it is imagine a large sheet of rubber stretched taugt. This represents space-time in 2 dimensions, the same would apply for a sheet vertical to this sheet, and so on. No placing an object on the sheet causes it to warp at the point of the object. The path of an object now rolled across the sheet will be affected by the first object, due to the warping. Without the warping the object rolled would have just rolled straight ahead, but spac-time is now bent, changing it's path.|||Well...this is a good question. I understand that "space" beyond the tangible universe is an area that is totally deviod of anything; even @ the microscopic infintesimal. So the fringes of space are moving into this matter-less area and once you have objects (any kind of matter) in this area you can draw two points of reference between said two objects, thus can call this area space. Past the fringes of the universe there is still space (or area; if measured between two objects) but it is totally empty and no distances can be messured because of the lack of points of reference.


The space craft will move through this void but the distance between it and the fringes can be measured and again be called space. But probably not true empty space...anyway that is up for discussion. Now remember all these ideas and including many from the leading thinkers are just theories. Anything or any thoughts are possible. You or I could possibly figure out how it works...wouldn't that be thrilling. Happy thoughts.





Some additional thoughts on the latest therories: When the discription of space is explained as being flat or like a sheet or trampalin with a bowling ball on it. That does not mean space is actually shaped that way. The afor-mentioned discription is only to give a visual discription for our little brains to focus on and picture (mine included). When an object (like the sun) sits in space, it has a gravitational pull on smaller objects. (These smaller objects can defeat said gravity using speed, but that is another topic.) It is now believed by some leading physicists that there are tangable, material (things with mass)-(another topic to be discussed on it's own)that reach out and physically grab the smaller object and pull it in. We have no way @ the moment to detect these little criters, because they are so small; perhaps a trillion x's a trillion to the trillionth squared smaller than the smallest partical that we know exists. From what I understand (and I have trouble understanding the math because @ these sizes the math is also being discovered and/or being invented) there are people out there who are making a serious attempt to idenify and prove their existance.