Particle synthesis



Particle synthesis was a technology which enabled the creation of artificial environments, in much the same way as holograms, but much more advanced and difficult to detect.

In 2374, Arturis utilized particle synthesis on the USS Dauntless, in an effort to fool the crew of the USS Voyager into believing that the vessel was of Starfleet origin. 

In 2375, Species 8472 utilized particle synthesis in combination with holographic projections to recreate Starfleet Headquarters in their terraspheres, with which to train operatives to infiltrate Starfleet. 

Apocrypha
According to the Pocket Books novel Greater than the Sum, particle synthesis is related to the Quantum Slipstream technology. In the novel, it is explained that the particle synthesis works by exploiting, and altering, virtual particles on a quantum level.

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