Doesn't that exclude/ignore a lot of other possibilities?
Meant to ping you to post #75 above.
As I posted, only what we know, not, what can be postulated. But, from what I have read about the theories on other dimensions, would we even be able to understand such creatures as life? I like the string theory 11+ dimension approach, but, communicating data into and out of the extra dimensions is going to be problematic.
And, they would be extra-universe life. In our universe, the laws of physics seem to be universal, so, any chances at life would have to stay in those known universal laws.
It is kinda obvious that if you were a super advanced form of life you would be real experts at hiding and remaining undetected.
(If not you would have been toast a _long_ time ago...)
That is why “we haven’t seen it, therefore it does not exist” just does not work in this realm.