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Where does the real matter go that you bring in to the Holodeck when the program ends?
I was watching Voyager last night and with all of the girls they seem to program in to the Holodeck, and everyone seems to enjoy quite a bit going in for a visit it became obvious what happens to the objects or matter you bring in and leave there?
For example if you were to bring some "water" in for your visit with a young lady, and then give her some, she would now have this real water inside of her projected/forcefield image. I would imagine it would stay contained within her until you turn off the program at which point she would disappear and any contributions you have made to her would then be left on the floor. I mainly got to thinking who cleans the damn thing out if everyone is going in there to get their jollys off.
I am sure one option is that the replicators are able to also dematerialize matter the same way they create it, if this were the case this "water" may have DNA in it and would be a living thing and the failsafes would not allow for it to be destroyed or else you would risk being dematerialized your self when the program ends as humans are just bags of complex liquids and several membranes. In addition, while it would be very cool for the replicators to be able to "refill" with matter that it takes apart, I do not recall any mentions of that happening in the shows in which case I could see them putting bricks of various matter in the replicators to refill them from time to time.
In the end I just see it being a good idea to put a garden hose and squeegee in the holodeck so when you are done you can clean your own mess up.