Did you read it who created the wormhole in the movie? I think Wormhole does not occur naturally.
Not that any wormwhole was ever observed to anyone check if they can be created naturally or not
Wormholes are naturally occurring all the time and almost everywhere, do your research on quantum physics you will get your answer. Practical proof is non existent because we cant observe it or posses enough power to recreate it but theoretically it has been proven.
I couldn't finish gravity.. there was no storyline or scifi that got me interested. I don't get it. Interstellar on the other hand.. probably the best space move I've seen. They actually apply quantum mechanics too.
The story of Gravity is simple, it tells us how precious Gravity really is to us that we take it for granted and never notice it, people that dont understand this simple concept are .... well.. lets just stop there.
Just because someone didn't like the movie, it doesn't mean they didn't understand that concept. If that is the main point of the movie, and I wouldn't have bothered watching. Interstellar had a much, much better plot. It incorporates quantum mechanics, you get to see other planets with water (that planet with the huge tidal waves was awesome), there's an actual story, and the concept of time dilation was pretty awesome.