You and I think alike on this stuff.
If man could build a spaceship with enough fuel to travel
beyond the solar system at 150,000 mph, it will require
566,928/30 = 19,000 generations of human breeding to reach
that foreign solar system.
Nice material for science-fiction! But it really is just fiction.
As for communicating with those aliens, it will require 127 years plus for each message to reach the aliens. Which means your great-great-great-great-grandson will have to receive the answer to message sent by you (254 years+).
We have clues about 'other dimensional realms' yet we ignore these clues because they come to us from sources like the Book of Daniel, Old Testament. I would contend that the scene in Daniel Chapter Five, or the upper room following Christ's rising from the tomb, are possible because there are temporal differences, like linear time, planar time, and volumetric time. And the 'mediator' of these other expressions of time will be 'force carriers different from the photon as we experience it; perhaps the sensing capability in these other realms will sense the planar nature of the photon's reality, rather than relying on the arrive of linear past data.
I'm in the process of writing a book on the subject, but here's a severely abbreviated hint:
The unit/limiting factor of our perception is the photon. A photon leaves a star billions of years away, yet when that photon reaches Earth, it is still in the present of when it left the star, thereby bringing us a past state of existence impacting our present state of reality.
Photons exist trapped in linear time, traversing the universe as points, or perhaps linear elements/string things ... the universe of a photon is limited by the linear temporal state.
Linear time has 'the same time' all along the linear pathway from source to target. A linear state exists as a portion of an infinite number of planes, which of course makes up a volume.
Because these units exist within a plane which exists within a volume of time (the expanding universe bespeaks a volume of time), things like the two slit experiment display wave characteristics, such that photons/electrons, etc. seem to pass through both slits as the photon moves from source to target.
A linear existence, in a volume of time, nets a planar reality/effect (a 'presentness', if you will). The photon is actually carrying a past temporal state ... we sense only that which has already occurred.
Only upon reaching a target does the linear existence terminate the planar effect, netting a point of past data. Linear exists within the limits of planar, and planar exists within the limits of volumetric.
Cutting to the chase, so to speak, it may be that the beings using these interstellar traveling devices are made differently than us, perhaps sensing the force carrier photon differently than we do. There travel may be hallmarked by a completely different temporal limits than what we have so far discovered.
A last clue from the Bible might be instructive: We are told that God made Himself a little less than the Angels, to take a body and dwell among us in the person of Jesus. Jesus made an effort to help Philip understand this as reported in John Chapter fourteen and elsewhere.