Because it's not a thing among things. If it were possible to explain it then by virtue of that explanation it would be dependent on something else vis a vis the explanation and we'd be stuck in the loop again. I guess, for something to actually be uncaused it must necessarily be without explanation.
Yeah, this has been bugging me ever since I read Smith's Khalam cosmological argument for atheism in the Cambridge Companion to Atheism (2006). I'm no mathematician, nor am I a physicist so I'm not sure if I understand it.
God cannot be a part of set A and hence cannot be said to act as a prior logical state of the universe, seen as one logical state does not imply the causation of another logical state. I do believe this is compatible with islamic theology?
Excuse any typos or grammatical errors, I'm pretty blurry-eyed ATM.