Star Trek: How Do Replicators Actually Work?

When we think of obstacles to interstellar or even just interplanetary travel, problems like fuel and cryosleep immediately come to mind. But one of the most significant problems humanity must overcome is how to provide nutrition for an entire crew during the months, years, or decades spent with nary a soil sample in sight. In the world of "Star Trek," there's a simple solution for feeding a ship's crew: replicators. Contrasted with today's world where most people toil away endlessly to keep up with the ever-inflating costs of food, clothing, and housing, the replicator represents the mark of a post-scarcity era, freeing humanity to focus on exploration and the pursuit of knowledge and the arts. The future's answer to microwave ovens, replicators are small enough to be installed in every room and accessible enough that a child can use them. Crucially, they are capable of creating just about anything a Starfleet officer could want (just as long as Starfleet's safety protocols and regulations allow for it). By the 24th century, replicators have become so ubiquitous that cooking has become more of a hobby or art form than a necessary life skill.

The ultimate recycling machine, replicators are the evolutionary successor of the protein resequencer technology seen in "Star Trek: Enterprise." Using transporter technology, they work by completely deconstructing matter and then reconstituting it into a desired product. But unlike Starfleet's existentially frightening transporters, which rely on molecular imaging scanners, replicators use a quantum geometry transformational matrix field to fill an order based on a stored pattern matrix — which is why if the ship can only create things it has a recipe for.

Just like today's astronauts recycle their urine, Starfleet saves space by recycling other types of matter, even the kind we don't like to think about. Responding to a "poop question" from a curious group of schoolchildren in "Breaking the Ice," Chief Engineer Trip Tucker explains that like just about everything else aboard their starship, human waste is recycled in the biomatter resequencer. "The waste is broken down into little molecules and then they get transformed into any number of things we can use on the ship — cargo containers, insulation, boots — you name it," Trip specifies.

While the resequencers would eventually be replaced by replicators, the basic principle behind the technology remains the same a millennium later in the 32nd century, as emphasized by Fleet Admiral Charles Vance (Oded Fehr) in the "Star Trek: Discovery" episode "There is a Tide..." to Osyraa (Janet Kidder). After revealing that he had never eaten a real apple, Vance tells the Emerald Chain representative, "It's made of our sh**, you know. That's the base material that we use in our replicators. We deconstruct it to the atomic level and then reform the atoms." And although some audience members might find this "Star Trek" revelation somewhat horrifying, Vance is quick to add that all things considered, their reconstructed waste actually tastes "pretty good."  

The mechanisms behind the replicator waste recycling system is further outlined in the "Star Trek: The Next Generation Technical Manual," which explains how the ship directly recycles anything it can. Anything that cannot be directly recycled gets broken down first including waste. As Michael Eddington (Ken Marshall) tells Benjamin Sisko (Avery Brooks) in "Star Trek: Deep Space Nine," they both know they're really eating replicated protein molecules and textured carbohydrates ("Blaze of Glory").