The Alcubierre Drive, a representative concept of "warp-drive" engines that could exceed light-speed, is referenced to suggest that such a technology would not only be a practical prerequisite for alien visitation, but also a means of communication that would render electromagnetic communication obsolete. The Fermi Paradox can thereby be resolved as a non-paradox due to our comparatively primitive technological commitment to electromagnetic transmission.
It is an enduring puzzle, The Fermi Paradox: Accepting that life, even highly technological life, likely exists in the universe, there is the confounding question of why we have been unable to detect their communications.
I believe the most plausible answer to the paradox is suggested, indirectly, by the idea of superluminal travel - travel faster than the speed of light. "The Alcubierre warp drive" is a concept of theoretical physicist Miguel Alcubierre at the National Autonomous University of Mexico . He speculates that a spacecraft could travel faster than light if it could be somehow driven by an expansion of space behind it combined with a contraction in front. A relatively simple parting of space to the front might be a sufficient and more practicable technique, but given our current level of technology, ours is not to reason how.
Whether some such "warp drive" could ever be possible may be beyond our ability to predict or even realistically conceive, as was the electric motor not so long ago. But there is reason to believe it can somehow be achieved: If we arebeing visited by those strangely silent interstellar and even intergalactic civilizations, superluminal travel would be a necessity. Light-years, light-decades, and light-centuries separate us from the cosmos, and the fleeting and questionable alien visitations in evidence would be hardly worth the trouble if light-speed is an actual limit. * The very fabric of space would have to be delimited by some means for it to be practical.
If we are being visited from afar, if superluminal travel is possible, an implication provides a likely solution to the Fermi Paradox: If the technology required for such travel would involve an onboard warp-drive mechanism, then radio waves, being simple and irreducible physical phenomena, could not possibly be outfitted.Interstellar communication would require superluminal transportation, comparable tothe carriers in pneumatic tubesystemsused in drive-through banking - except the carriers in question would have to provide their own propulsion.
Superluminal transport across the light-years would render radio signals obsolete. So for the Fermi Paradox: It may be the reason we don't detect radio signals from the cosmos (or signals of any wavelength) is that radio, except for civilizations in relatively brief periods of early technological development, would be unacceptably primitive and slow.
If superluminal travel can be driven in Alcubierre-like vessels, and interstellar communication can only be practically transmitted via some type of accommodating warp-drive capsules, interstellar visitation becomes more plausible, and the apparent absence of radio communication from the cosmos becomes explicable: It seems likely that advanced alien civilizations exist, and may visit us at will; they just don't bother to communicate via electromagnetic (i.e., luminal) transmission.
* There is a curious inconsistency between the common belief that there must be advanced civilizations in the universe and the common disdain for any suggestions that they have actually been visiting us.