I'll admit that I have a hard time liking short stories. I feel they're rarely long enough to paint a picture that interests me. The first couple of stories were pretty uninteresting for me.

The three Merlin stories picked up the pace - they're separate stories, but featuring the same universe and protagonist.

A lot of the stories are about alternate realities and quantum theory. One story is about opening a communication channel to an alternate world, identical to ours up until the very moment of contact, where quantum theory tells us that observing something changes it.

Another story speculates about quantum immortality - if you die from an accident in this world, there are other worlds where you survived. And by extension, there is a world where you never die at all - that last dying breath is always followed by another one in some alternate world.