...I still don't understand how they are able to share the same dreams?.

Honestly, I've never questioned the basic premise of Inception. Apparently they just need a sedative, some might be stronger to put them down to deeper levels, but ultimately, there's no explanation how they are able to share the same dream.

Did I miss something? Is this a world populated by psychics. I thought maybe there were wires or transmitters built into those tubes they stick into their bodies with those suitcase devices. But nope, that's just the liquid to put them under.

So how does the rules of the Inception universe work? Well, if you can ignore that huge logic issue, then it makes sense. I guess you could argue that it's all just a big dream, right from the very beginning, based on what happens at the end. But even in a dream, there should be some explanations. Or maybe that's the point.

Anyway, the movie is a fun ride, if you ignore that gaping lack of explanation on how they share a dream.