All particles interact via gravity, dilation of time-space, regardless of their dimension. The missing mass of the universe could be accounted for with mass which is orthogonal to 4D space-time ( not anti-mass, which would combine with normal matter ).
Since time is slower at the bottom of a gravity well, doppler shifts occur. The distance of Quasars has been calculated based on their doppler shift, and their apparent size and energy output calculated accordingly. However, considering the doppler shift due to gravity, the Quasars are actually much closer, and their magnitude much smaller. Consequently, the apparent energy output of Quasars is also much lower ( and does not defy the mass-energy ratio e = mc^2 ).
The apparent mass of an object becomes infinite relative to an object which is accelerated to near the speed of light. However, the mass of the object in its own frame of reference remains constant. Although it is impossible for us to accelerate particles to or beyond the speed of light, a vehicle may accelerate itself to any speed. When a vehicle would reach c, however, the universe will have infinite mass relative to the vehicle, and the vehicle would be torn apart. (These gravity forces might cancel, however, if equal and from all directions.)
The primary difficulty in accelerating particles to near the speed of light is that the time of the particle approaches zero, so that further acceleration becomes exceedingly difficult. Energy and mass are equivalent, since mass is stored energy. Storing energy becomes difficult when time approaches zero because the rate of energy transfer also approaches zero.
Theoretically, the energy required to accelerate an object can be recovered in decelerating the object. Consequently, moving from one point to another in space requires no energy. In order to travel large distances in very little time, the light barrier should not be crossed since, besides being torn apart, the vehicle would experience zero time and not be able to return to normal space-time. In essence, attempting to cross the light barrier is similar to attempting to leave the boundary of space-time.
By distorting space-time it is possible to move very large distances by crossing through the distorted space-time. If space-time is stretched, then two points near the center of the distortion become farther apart. If space-time is compressed, then two points become closer together.
How can space-time be compressed? Space-time is distorted in matter. The distortion due to matter extends out into space-time. This distortion can be directed and extended by controlling the "snap" which occurs when matter is converted into energy. In essence, by directing a nuclear explosion, a controlled distortion of space-time will occur. If the "snap" results in space-time compression, then a strong directed compression of space-time will occur. If the vehicle is also moving along the direction of the distortion when it occurs, then the vehicle will travel in very short time from one point in space-time to another point which has been brought into close proximity. When space-time reverts from the distortion, the vehicle will be in another location.
Since matter formed in the Big Bang under a state of compression, a release of the space-time in matter will result in a compression of space-time.
Since space-time is one and the same, if this theory is extended to its logical conclusion, any point in space and/or time of space-time can be reached. However, time displacement would require isolation of time from space-time during movement. Since space is linear, compression of space-time would compress all dimensions equally. However, if location can be isolated by directing the compression, then perhaps time might also be isolated, for instance, by controlling the rate at which the transition is made.