Bless Dr. Kaku, but on Meathead's show he's stringing together a lot of suppositions to loft the idea that what we're seeing on earth are real visitors from extraplanetary civilizations. Well, sure , that's strictly
possible, if
all that stuff he proposes is true
- among them, there being an advanced enough civilization, figuring out how to harness Planck energy (especially how to make it work for 'destabilizing space and time' or traversing wormholes in such a way that a living intelligence could
actually survive travel by that means), and these amazing aliens deciding Earth, among all of the places one could visit in the universe, is so very interesting. The Kardashev civilizational typology Kaku cites , which dates back to the 1960s, is of course, purely a thought exercise -- we don't
know any Type II or III civilizations, and we aren't even *really* a Type I yet -- and surely 'typing' a civilization itself is more complex that simply gauging its energy generations and consumption technology?
These are fun ideas but essentially a form of
science speculative fiction. Decades ago Kardashev predicted that we would within a few years find solid proof of extraterrestiral civilizations. Alas, reality happened
differently. But astronomy coughs up these entertaining, prophetic characters almost regularly. Avi Loeb, the Harvard guy, is our current one. (Or maybe it's just a
Harvard thing ...)