We can never see beyond our observable universe, we can never measure what's going on in a black hole, and we can never know precisely the position and momentum of an electron. I'm not talking about anything spooky.
For the first two, that's definitely not "indefinite", as you propose. Theories on on how universes are birthed are being hotly debated right now. Whether or not they are truly untestable remains to be seen. I wouldn't be so hasty to proclaim that this is unknowable. I mean, if you are able to invoke this idea of the "unknowable", then why can't another just invoke the idea that the "unknowable" is just unknowable in the current context of our understanding? They're both nebulous statements, but at least the one I provided has a verified method that has predicted and categorized nearly every facet of nature that humanity has come across.
As for black holes, we don't have to measure inside of them. We can know how they function by theory and other forms of experimentation. Once again, in order to understand them will take (likely) many more years of bridging the gap between the theory of gravity and quantum mechanics.
For your last one, that's a common misunderstanding: with particle-wave duality, position and momentum aren't definite things like in our Classical world. That's largely because they are probabilistic. These visuals and summaries should help explain it:
http://hyperphysics.phy-astr.gsu.edu/hbase/uncer.html#c1
Here's an analogy to illustrate how this is not a case of the "unknowable":
http://newt.phys.unsw.edu.au/jw/uncertainty.html
Honestly, I'm not seeing how any of these examples are "limits" to human understanding. Furthermore, and this isn't meant to be an attack on your integrity, your argument comes off as an appeal to ignorance.
In relation to the thread: has supergiz checked to make sure his carbon monoxide detector wasn't malfunctioning or off?
