In Star Trek's time, there are many more quantum particles, known in particle physics today as "quasiparticles". The article explains the significance of their movement. ProfessorTrek 02:38, July 8, 2011 (UTC)
Some high-energy particles move erratically as they leave their emitters, due to gravity or one of the other universal forces, such as electromagnetism or the strong and weak nuclear forces, interacting with the particle. This is analogous to a shooter having to compensate for wind and gravitational effects on a bullet he is firing at long range.
The phrase "compensating for particle drift" likely is a reference to an episode of Star Trek: Enterprise where Lt. Reed is showing Hoshi how to use a phase pistol. The previous, standard-issue sidearm, known as the EM-33, apparently is affected by particle drift, either because of gravity or electromagnetic forces, whereas the phase pistol is not.
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