This article is from the Star Trek Tech FAQ, by Joshua Bell inexorabletash@hotmail.com with numerous contributions by others.
These were mentioned in "Parallax" [VOY], and used to open a subspace
breach in an event horizon.
The objection has been raised that warp particles have never been
mentioned before. However, fields and particles are different ways of
looking at the same thing. You can even consider soliton waves
(cohesive waves which don't disperse) as being made up of a special
soliton particle, or sound to be carried by a "phonon" particle, and
it makes some calculations much easier than considering the wave or
field classically.
Quantum mechanics says that for things like photons, electrons, Higgs
bosons, etc, the particle/wave/field distinction is pretty much
meaningless. So "warp particles" could refer to the specific particles
making up a warp field, or the entire class of particles which partake
in subspace reactions (tetryons, verterons, etc).
 
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