Will it be possible one day to share dreams?
Inception's emphasis on story over technology works, and is yet another example of director Christopher Nolan's mastery of unconventional story progression (see: Memento). But it's still worth taking a look at the technology that allows fictitious characters to experience—and influence—the dreams of others.
To promote the movie, Warner Brothers featured the dream machine the protagonists used to work their somnambulistic magic. The PASIV (Portable Automated Somnacin IntraVenous) device is a movie prop that drives Inception's story.
According to WB, the machine's "Lithium-iodide" batteries provides up to 200 hours of power. A "LED display with atomized timer" provides the operator with continuous system updates. Numerous IV lines allow multiple users to essentially network their respective dream states, with one person acting as a conduit for everyone to hallucinate around.
Truth be told, there isn't much to work with. WB went through the paces of creating a fictional manual governing the use of the PASIV device, which even lists the machine's primary components. Yet it falls short of actually specifying anything readers can use to speculate on its actual operation. How can a mere IV—mainly used to constantly pump fluids into the human body—allow people to exchange ideas through dreams? What kind of system shares the subconscious of many people, without any lasting damage, except under very special circumstances?
Still, a future that allows people to exercise some control over dreams with some training—and experience entire lifetimes in one sitting—sounds very exciting. The PASIV is a concept that can potentially inspire researchers and inventors to produce real-world technology that lives up to the fiction, literally opening up possibilities limited only by our imagination.