Depends on what exactly you mean by Quantum Physics. The field at this point is all over the place. My favourte accessible book (though it's mainly about String Theory) on the topic is Brian Greene's The Elegant Universe. It gives a good ground in Quantum Mechanics, too.

Of particular interest to you, I think, would be another favourite: (that dips into parascience a bit so it's not my introductory text) Michael Talbolt's The Holographic Universe.

And in my world, actually writing it is the most kind of worldbuilding. Unless you're running D&D.