What is a dream, anyway? Most of us don't live in our bodies even when we're in the so-called awake state. Our attention is drawn to the past and to the future most of the time. How rarely we are 'in the now.' Unruly imagination generally holds sway as our attention hops from one subject to another, drawn by something we scarcely bother to think about - an egoic mind having its own way. This, of course, is not the real us.
When we're asleep an even greater part of our awareness is outside of our phyical confines. And with such freedom all sorts of wonderful and awsome events occur. No, I doubt they're just micro-electronic traces in our brains. These are just effect not causes. We (and that's the crux of the matter, this we or I) really is out there living our immortality.
And yes, some dream-like states can portray future events. Of that I know from experience.