I know for a fact that cerebral flatulence occurs. I'm not so sure about multiple universes, much less travel or communication between them.

But while we're on the subject, I'll throw more fuel on the fire. I've had dreams about places, and events, which I've visited or experienced only in previous dreams. In one in particular, I dreamt of being lost, and approaching a street intersection I suddenly recognized. The whole world rotated as my tentative coordinate system suddenly aligned with the real world, a feeling I know we've all experienced when lost and finally figuring out where we are. I even remember telling myself (in the dream) "Oh, now I know where I am! I remember the last time I was here...". Except, of course, the last time I was "there" was in another dream I had about a year earlier, one that I distinctly remembered because it was so bizarre and vivid. The place and events in question were similar, but different to real events and places they corresponded to in the real world, something I knew when awake, but which wasn't apparent to me in the dream. I also had dreams where I dreamt I Iwas dreaming. Believe me, it can be terrifying when you wake up from a nightmare only to find you're in another one!

Personally, I feel dreams are just some sort of internal maintenance program the brain runs periodically, sort of like a de-frag or file compress. Nothing cosmic, or psychologically or spiritually significant, just a process, like digestion. But it does bring up a very important issue. We interact with the universe through our consciouness. It really doesn't matter what reality is, what matters is what we experience. The "real" reality of particles and waves and fields and physical forces is not what we experience, it is only an abstraction of what we perceive through our senses. Our world is INDISTINGUISHABLE from the world of our dreams.

The Chinese philosopher contemplates "am I a man dreaming he's a butterfly, or a butterfly dreaming he's a man". And every child has asked himself the question, "what if all of this is just a dream?" I'm very interested in these phenomena, not because I think there is some supernatural or metaphysical process at work here. The universe probably doesn't need us, we're just along for the ride. What concerns me is that the process of perception and understanding and memory, consciousness, is the only metaphor we have available to us to interact with reality. We need to be aware of its capabilities and its limitations.