Quantum Foam is a concept in Quantum Mechanics, related to Virtual Particles in Quantum Field Theory. In a nutshell, the Quantum Foam idea states that at very small scales, subatomic particles can briefly pop in and out of existence without violating conservation laws, thanks in part to the Uncertainty Principle. These high energy particles must, by Einstein's General Relativity, bend Space Time - so unless a working theory of Quantum Gravity comes along and changes this in some fundamental way, the conclusion is that reality is constantly being bent in tiny imperceptible ways.
These subatomic folds of spacetime could be visualized as a "foamy" nature or texture to reality, constantly in motion. To a microscopic entity capable of perceiving such folds, it would look like a storm-tossed sea, with waves and particles crashing around.
According to the Chaotic Inflation theory, new universes are constantly being formed, with their Big Bangs happening in our Quantum Foam. These bubble universes break off from (or at least isolate from) ours, but in the process they cause the the expansion of our universe.
Game and Story Use
- Quantum Foam might be the barrier that limits Time Travel or Dimension Hopping. In order to get to another dimension, a parallel world, branching time or Heaven, you need a device that either magnifies or calms the foamy nature of time. It's probably the GMs call on whether you want more or less foam, based on what kind of imagery would fit the campaign.
- In the real world, some scientist conjecture that Quantum Foam might actually have microscopic wormholes and hyperspatial links to other parts of the Multiverse. In fact, one theory of how to achieve a usable wormhole would be to inflate existing ones from the Quantum Foam. This might require less energy andbe less damaging to the universe than making a new wormhole from scratch. Along the lines of how stretching a rubber band is easier and less damaging to it than say, cutting holes in a rubber band.
- Quantum Foam may be a resource. Perhaps some new technology comes along to physically make foamy matter. It may be the by-product of a new subatomic reactor, or be something you have to intentionally set out to make. It would make a good Phlebotinum, possibly with Quantum Powers, or enabling FTL. It might modify Probability, or serve as Armor proof against any energy or matter attack.
- Quantum Foam may be a condition (meaning GM's choice of either medical condition or state of being). If some accident, disease, negative space wedgie] or weapon turned you or the spacetime around you "foamy" it might be terribly debilitating. It could disrupt your neural pathways, confuse your brain, immobilize your muscles, knock you out of phase, turn you into a fourth dimensional lifeform, or cause you to randomly dimension hop into a whole new reality. Have fun with it!
- The PCs are shrunk down a la Fantastic Voyage, and expect to travel between atoms or cells. Instead, they discover Quantum Foam is real, and at this scale it's terrifying and destructive! Can they survive the perfect storm till the shrinking process wears off? What Butterfly Effects will their actions on this level have? Which reality do they end up in when their shrinky-dink status is countered?