GRRR
Well now i'm really pissed, I just spent about 20 minutes explaining my theory then the page moved back and I lost it all, well I'm gonna rewrite it due to the importance of this theory to me so here goes.

These theories about to be stated all began with time dilation chapter in our physics book after I was going to study for the retake I have to do with Mr. Valente. The picture below shows that of an expanding universe spiraling outward. For these theories I will assume the universe is spiraling outward from the C.U. (center of the universe). I will later assume that it is not spiraling but expanding in a 3-Dimensional pattern, possible more, but I am yet to theorize on that so here goes. In the picture below it assumes that time is not a rate, but more the location of the object you are measuring in reference to the expansion of the universe. As you spiral outward further from the center of the universe you approach different "times", we will assume that the rate of which the universe expands is constant for these theories but I may later theorize that the rate is accelerating, which I believe is what is commonly accepted due to the electromagnetic spectrum analysis. So here begins my theory...
The velocity at which the universe expands, let it be the variable c. When you travel at variable c, if you are inside the universe not moving in reference to visible objects, the rate of which you approach different times is constant, which would be c. If you gain a velocity, the rate at which you move to different times slows down, because vectorially assuming the universe is more then 3-Dimensional no matter which way you move (unless possibly you know which way the universe is expanding), when you gain a velocity you will be moving slower then c and against the expansion of the universe, but you will not be moving back in time, just slowing the rate at which time changes. If you are on a bus that is moving at a constant velocity and you walk opposite the direction the bus is moving, but slower then the speed of the bus, you will still be moving the same direction as the bus, just at a slower speed. To apply this to the universe if you are moving less then c, or the speed of expansion, you will still be moving through time just not at as fast a rate as normal. Now back to the bus, if you are moving opposite the direction the bus is moving with the same speed, if the bus had an infinite length, you would be at the same location until you or the bus changed its velocity. In context with the universe, if you are moving the same speed but the opposite direction as the expansion of the universe, you would be stuck in one time and time would not move for you. If you move faster then the bus is moving in the opposite direction, you would approach previous locations you and the bus had been to. If you move faster then c in the opposite direction, you would approach previous "times" that you had been in before. If we were to assume that the Universe was a spiral tunnel from the inside that keeps expanding outward and you with it, like a spiral tube with water constantly being shot through it and you are trying to travel the opposite way the water is. You would have to reach the same speed of the water in the exact opposite direction of the water (although it is constantly changing due to the spiral) to visit previous times. You cannot skip a previous time to get to one before that and it would be extremely hard to calculate at what speed you would have to travel to get to a certain time because if you are not traveling the same direction of the inward spiral only the speed which is towards the inward spiral would bring you against the expansion.

Now your probably wondering how to approach the future. Well we cannot approach our future because it is the end of the tunnel. If we were to assume our present is the end of the tunnel, but is curved, if we tried to move in the direction of the expansion of the universe, we would be like entering an arc. We would enter the arc at a certain speed + c and leave the arc going the opposite way of the expansion of the universe at a certain speed + c and we would be leaving the arc going back in time at a certain speed, if this was true then we would keep traveling back in time because in space there is no friction in this idea. If we were to say the universe expands at an accelerating rate, this would work, because as long as our speed isn't great enough to reach the C.U. the universe would accelerate and eventually we would be moving with the acceleration of the universe again.

The easiest way to explain all this would be to imagine the universe as an expanding string from one side. The string is in an outward spiral that keeps increasing in length on one side and if you were to mark a spot on the string you were now, as the string lengthened and you were always located at the end of the string, the mark would appear further and further away from you. That mark represents a certain time.

Now let me think upon the idea that if the universe wasn't spiraling outward...
If the universe was expanding in all directions from a center, accelerating its expansion rate. In the 3-Dimensional view this is very interesting because as the object expands away from the center ofr the universe would it be moving upwards or downwards away from the object? If it were moving neither and just horizontally away from the C.U., the object would have to have an increasing rotational and linear velocity to remain in orbit with the C.U., as its radius from the C.U. increases. This would become the same thing as an outwards spiral because if the universe is expanding and orbiting the C.U. it would create an outward spiral. The only way around this would be to assume that something is attracting these objects outside the universe, which as the outside of the universe gets closer to the object(s) that are attracting the universe, it would have a larger attraction and thereby accelerating it. Although it doesn't seem practical, this would be able to explain the acceleration of the expansion of the universe if the universe didn't accelerate at a constant rate. I believe though if the universe did accelerate at a constant rate, this expansion wouldn't be needed because once the universe started expanding it would keep expanding at the same accelerating rate. This is where my knowledge, limits me, if you pushed someone in space and they were traveling at 10 m/s in 10 seconds would they still be traveling at 10 m/s or would they be accelerating? I believe they would be accelerating and at a constant rate of acceleration.