Why is there far more matter than antimatter in the observable universe?
The solution to this puzzle could be a double agent; a particle capable of playing the role of matter or antimatter and introducing a tiny asymmetry in favour of matter. This double agent must fulfil two conditions: it must be an elementary particle, and it must be neutral because electric charge is inverted in the other side of the cosmic mirror. So a neutral double agent candidate could behave as both.
The only particle that meets these requirements is the neutrino. It could mediate reactions leading to a slight excess of electrons and of quarks in the early universe. Thus the balance would be tilted to the matter side and the universe would «survive».