Q&A: Dark Matter

Q:
Could parallel universes be the answer to the dark matter mystery?

A:
The solution to the dark matter problem may well involve something very close to a parallel universe. This is shadow matter, matter that interacts very weakly with the rest of the universe only through gravity. The key to proving this hypothesis is the phrase "very weakly." If the electromagnetic or nuclear interactions of shadow matter with the rest of the universe is not exactly zero, then it may be possible to detect by some means other than its gravitational effects

The idea for shadow matter comes from some theories that attempt to unify gravity with the electromagnetic and nuclear forces. These theories predict that every fundamental matter particle should have a massive "shadow" force carrier particle, and every force carrier should have a massive "shadow" matter particle. This relationship between matter particles and force carriers is called supersymmetry. For example, for every type of quark there may be a type of particle called a "squark," and for every photon there is a particle called a photino. No supersymmetric particle has yet been found, but experiments are underway at CERN and Fermilab to detect supersymmetric partner particles. http://particleadventure.org/particleadventure/