The universe isn't "expanding into a void". What's happening is that the amount of space there is is increasing and distances between things are increasing. As we measure the velocities of more distant objects, they recede ever faster. All parts of the universe see this expansion in a similar way. It doesn't matter where you stand in the universe, everything seems to recede from you. It is tempting to think of the "big bang" like an earthly explosion with a definite boundary, but this is wrong. A slightly better picture is imagining how two dimensional beings living on the surface of an expanding baloon see the world - each point on the baloon sees other points recede in a similar way (considering only distances measured within the surface of the baloon). But even this analogy isn't quite right, since the baloon has an inside and an outside, and space does not - you'd have to pretend that the surface is all there is, with no inside or outside or even places where they could go.

In my experience the easiest way to visualise universal expansion is the "currant bun model". Imagine the universe was a lump of raw dough and all the objects in that universe were currants randomly dispersed within. As the dough bakes it rises/expands not just as a whole but the dough between each currant also expands therefore, every currant appears to recede from every other currant regardless of frame of reference issues. It seems reasonable to say that there must be a sort of field of potential for expansion rather than a void outwith our universe, just as there must have been a potential for the initial singularity to create the universe in the first instance. Regarding the author of the question's obvious interest in the difficulties involved when dealing with frames of reference; there are several things in physics which are commonly known as fudges, whereby things are assumed to be the case in order to fill in small gaps in theories. One such fudge is involved in "the twin paradox" whereby, twins born similtaneously by c-section (quite a feat in it's self but please bear with me) named imaginatively A and B. A travels off in a space ship at near the speed of light, B stays home on Earth and puts his/her feet up. Years later A returns to Earth, what does he/she find? Did time slow for A making him/her much younger than B, or since from A's frame of reference the Earth appeared to be doing the moving away from the space ship has time slowed from B's point of view making him/her the younger? Special Relativity states that all frames of reference are not equivelant, only inertial frames. A's frame is not inertial while she is accelerating, as acceleration requires an external influence such as, in A's case, the firing of a rocket motor. Therefore which ever one feels the acceleration becomes the younger twin at the next meeting. This is all very neet and tidy or is it? No it's a fudge. General relativity says that A could claim to have been motionless the whole time, and that a gravitational field swept through at precisely the instant her rocket motor ignited sweeping everything else away while he/she sat still. Also given the Earth has a reasonable gravitational field of its own is B's frame truly inertial? There is a simple solution to the debate, just build a vehicle capable of prolonged near light speed travel and have a go. There's a good science project for little Jimmy.

The trajectory of the expanding Universe is relative to the coordinates of a space shuttle. The flight has been predetermined, the coarse has been set, the only thing left is to carry out the mission. Cause and effect would be the best way to predetermine the coarse of where or what the Universe is expanding to. Were just riding the primordial wave. Once this vibration subsides, I'm sure gravity will cause the universe to collapse into a big crunch with a Black hole sucking itself inside itself Eliminating all existing eleven demensions in the hyperspace model. It's like a bomb, perhaps you can find several different uses but the of the basis for what it does is an internal soarce based on what chemical and physical properties make it do what it does. And what kinds of kinetic-potential energies and forces are involved. The biggest thing to remember is that time restrains the Universe, holds it back from ever reaching an infinate velocity, which leaves us able to question the outcome based on a system which is obvious that entropy models and mathematical insight could solve.