About those UAPs and aliens

 

Here are the problems with “Aliens” coming to visit us.  First is the idea that a lot of complex life is out there. We don’t think it occurs all over the place.  In order to have a complex organism (brain, arms, eyes, stomach, etc.) you have to have cell differentiation.  Cells have to know if they are a liver cell or a toe.  And that means that a simple bacteria cell without a nucleus is not enough.  You have to have a nucleus and a ribonucleus and mitochondria.  The only theory for these that astrobiologists have come up with for the presence of all these things within our cells are two extreme chance events, the snowball earth episodes.  The first one 2.7 billion to 2.2billion years ago featured an ice age so long it covered all or most of the earth, and for 500 million years.  After this it seems that nuclei appeared (hard to verify).  The second snowball earth evolved the ribonucleus and mitochondria.  The thinking is that individual cells of bacteria were so distressed by the cold conditions that some symbiosis occurred that caused one cell to live within the other.  If that is true, we should find bacteria everywhere but complex life only once or a few times in a galaxy.

Since the galaxy is so large it is unlikely that this happens closer than 10,000 light years apart. 

Secondly, to travel such distance would require travel faster than the speed of light. But that creates time travel problems.  Going faster than the speed of light means going backwards in time.  So you have the Back To The Future problem.  What if you go back in time and change something?  When you travel forward then, the world becomes a different place than it was when you left.  And that causes violation of casuality and other problems.  So some have said that any backwards time travel would be highly restrictive to not change the future and maybe even won’t allow awareness of what you observed from the past. 

Put this together, and say there is 1000 light years distant from you and a planet you find you want to investigate. You’ve figured out how to violate the speed of light. Likely you will use an unmanned drone to do this in which case you have to transmit back at the speed of light and can travel at whatever speed you can achieve.  Whatever the case it will take >1000 years to find results of  your investigation.  Are you willing to wait that long? What if the transmission is forbidden? What then?  Are our UFO events really just drones from somewhere else?  If on the other hand, if the transporters contain real life, that presents a huge problem with our current understanding of general relativity and quantum mechanics.