Chroniton

A chroniton is a type of particle which is an expression of time. Its effects are typically temporal in nature. It has an opposite antiparticle, the Antichroniton (which is an expression of Anti-time). They pose no danger to Humans, however, they do have the capability to affect the systems in a starship following prolonged exposure.

Chroniton particles have a great effect on the Prophets and Pah-wraiths, entities which exist out of time. In 2373, a Pah-wraith inhabiting Keiko O'Brien had Miles O'Brien prepare a chroniton beam to fire at the Bajoran wormhole and kill the Prophets. O'Brien was later able to fire the beam at a runabout he and his wife were in, driving out or killing the Pah-wraith. (DS9: "The Assignment")

In 2374, the crew of Deep Space 9 planned to drive out two of these entities from Kira Nerys and Jake Sisko. Benjamin Sisko wanted the Reckoning to go ahead, but Winn Adami activated the chroniton pulse, driving out the Prophet and the Pah-wraith. (DS9: "The Reckoning")

Romulan Cloaking devices generate chroniton particles, which can lodge in the hull of the starship using it. In 2371, the chronitons lodged in the hull of USS Defiant interacted with a quantum singularity in Sol system, causing a transporter beam to be redirected 300 years into the past. O'Brien and Kira later used the remaining chronitons to search for Sisko, Jadzia Dax and Julian Bashir in the past. (DS9: "Past Tense, Part I", "Past Tense, Part II")

When Geordi La Forge and Ensign Ro Laren interacted with a Romulan phase cloaking field in 2368, they discovered that passing through objects (like walls) disrupted the molecular structure of those objects, generating chroniton fields. (TNG: "The Next Phase")

Krenim weapons were chroniton-based, allowing them to pass through enemy shields by being in a state of temporal flux. (VOY: "Year of Hell")

The Borg use chroniton fields throughout their vessels, projected through specially designed conduits. These fields are essential when Borg vessels travel through the Borg transwarp network, to keep the various parts of the cubes in temporal sync and minimize the temporal stresses on the vessels. The warp core of a Federation starship and the bio-neural circuitry can be reconfigured to create a similar effect, although temporarily. (VOY: "Shattered").

Background Information

Chronitons may be related to Chronometric Particles, but it is unclear how. It is possible that chronitons are a specific type of chronometric particle, of which there are others.

In quantum physics, the quantum (smallest possible part) of time is called the chronon. Chronons are defined as 10^-43 s. The name "chroniton" is a variant of this. However, chronons are not particles, simply the smallest possible intervals of time.