In TNG, Picard says that the Federation has evolved past a need for money. Indeed, we never see any.
In DS9 though, Quark talks a lot about bar tabs and costs. Surely OāBrien and Bashir donāt get free drinks, so how do they pay? Iād assume that any Ferengi worth his lobes wonāt accept anything that can be replicated, so do Federation officers get a stipend of tradeable āvalueā when interacting with cultures that still expect payment?
I think thereās also a reference to Quark paying rent to Sisko for running the bar. Presumably thatās denominated in latinum. I wonder where it goes? Maybe the secret āGarak black opsā fund.
A transporter is a device which takes matter, shifts it into subspace, and can do some manipulation of that matter in the process, but canāt reconstruct it arbitrary. Once the transported object has been rematerialized, all the transporter has left is a record of what that matter was at a far lesser precision than what would be needed to replicate it.
A replicator is a transporter designed to shift inert matter into subspace and modify it extensively from that state. A typical replicator is less precise than a transporter and is simultaneously limited by the complexity of its recipes. It cannot produce functional living things, for example.
Transporters and replicators are frequently referred to as matter-energy conversion devices. This is technically true but somewhat deceptive. Itās also a common misconception that a transporter is an advanced replicator, instead of the other way round, but we know this isnāt true: a safe-for-humans Transporter was invented and used in the 22nd century, while the contemporary replicator equivalents were primitive protein resequencers.
Havenāt they had multiple episodes where something is in the ābufferā of the ship? What is the buffer? Why canāt you just copy the buffer and put whatever you want into it?
First off, itās clear that the metaphor the writers initially had in mind was a computer storing data. The TNG tech manual is just vague enough to be ambiguous on this point, but very heavily implies a āscan and save a pattern -> destroy the original -> rebuild from the patternā process. Terminology like āpattern bufferā no doubt comes out of that conception.
Itās also clear that by the end of 90s Trek at least some people with decision making power felt it was really important to explicitly shoot down a lot of the ākill and clone machineā theories about how transporters work, which is why Enterprise in particular is full of counter-evidence. Of course, TNG Realm of Fear was clearly not written by someone with ākill and cloneā in mind, and stands as another very strong bit of evidence against that theory. The conflicting intentions make things confusing, but they are not irreconcilable.
My preferred explanation is as follows: When they shift something into subspace, they still need to keep an accurate track of exactly where in subspace everything is (the āpatternā), in addition to preventing whatever extradimensional subspace interference whosamawhatsit from damaging the matter itself. (If youāre familiar with computer programming, the pattern is functionally a huge set of āpointersā, not pointing to a specific piece of computer memory, but a specific point within the non-euclidian topology of subspace.) This pattern is stored in the āpattern bufferā, a computer memory storage unit with an extremely high capacity but which only retains data for a limited time. The transporter then uses this pattern to find the dematerialized transportee in subspace and rematerialize them at the target coordinates, taking great care to ensure that all these trillions of pieces are moved to the correct locations in realspace. These steps can be (and often are) accelerated, with a person beginning to materialize at the target coordinates while still dematerializing on the transporter pad (see TNG Darmok for an example off the top of my head).
The reason you canāt just tell the transporter to make another copy of whatās in the buffer is that although you have a lot of information about whatever you just dematerialized, you only have one copy of the matter in the buffer. If you try to materialize another one youāll be trying to pull matter from subspace where none exists: the transporter equivalent of a Segmentation Fault, to use another computer science term. If you tried to use that pattern to convert an appropriate quantity of base matter into a copy of whatever was in the buffer, youāll still be missing any information about the transported material which canāt be gleamed exclusively from a mapping of where each piece was: you wonāt necessarily know exactly what every piece was, at a precision necessary to recreate it. Especially if the diffusion of material into subspace is sufficiently predictable that the pattern doesnāt need a pointer for every individual subatomic particle, but can capture a a cluster of particles with each one.
We know from the existence of ātransporter tracesā that the transport process does leave behind some persistent information about a person who was transported. We also know that it is possible for the transporter operator to identify and deactivate weapons mid-transport. It makes sense that a mapping of pointers could be extrapolated out to get a lot of data about the matter being transported (such as detailed information on a subjectās cellular makeup, or if thereās a device capable of discharging a dangerous amount of energy) while still falling far short of the data required to make an exact copy.