13enigma - 9-12-2017 at 23:29
Can a device that replicate matter be impossible? If not how could it be achieved with modern day chemistry and physics?
elementcollector1 - 10-12-2017 at 16:44
Not having seen the reference you're referring to, my guess is that the technology would find its infancy in a coupling of optical tweezers and
targeted nuclear fusion. It'd be incredibly slow, require an absolute boatload of energy, and produce things a single atom at a time while giving off
waste neutrons - in other words, not very good. Also extremely impractical from a replication standpoint, as most things you'd want to replicate
consist of quite a few atoms (and therefore would take quite a long time to make).
I suppose if you found a way to automate and drastically speed up the process of moving each atom into place (like conventional 3D printing's
extruder/motor setups), you could speed up the overall process quite a bit, but we're not quite there yet in terms of technology. Also, that speed of
atomic movement would need to be on the order of around one mole of substance per minute (or 6.022 x 1023 atoms per minute) in order to
replicate something on a useful time scale.
MrHomeScientist - 11-12-2017 at 09:15
Wow... so I wrote all of the below thinking you were talking about transporters, not replicators. But I didn't want it to go to waste so here you go
anyway.
================
The Physics of Star Trek is a good book, and has a section on transporters. You have a choice: send the matter, or send the information.
(1) Send the matter. Physically deconstruct the object and fire the atoms in a coherent matter beam to the destination, where the atoms are
reassembled. Judging by what I can remember of the dialog in the show, this is probably what they do. People would need to be comfortable with being
essentially vaporized, for a while! This is probably the more energy intensive operation, since you have to accelerate matter and send it to a
specific destination. It's also more susceptible to error since if you lose an atom in transit, it's gone. That could be bad.
(2) Send the information. Scan the object to get quantum state information on all its atoms, then transmit this information to a receiver where the
object is reconstructed using local matter. Less vulnerable to errors since it's just a data stream, and bits can be reconstructed. You'd need a
supply of useful atoms at every receiver though. If the scanning process is not destructive, you then have to figure out what to do with the original!
If it is destructive, is the reconstructed object the same object, or a new one? If it's a person, is it the same person?
============
Replicators have similar issues, in that they need assemble an object from atoms. A replicator is essentially an advanced 3D printer that builds thing
atom-by-atom instead of layer-by-layer. Conceptually a short leap from current technology, but practically quite a lot harder. The Physics of Star
Trek also has a section on this technology, but I don't remember it as well.
[Edited on 12-11-2017 by MrHomeScientist]
NEMO-Chemistry - 11-12-2017 at 09:31
You watch, 50 years time these will be like 3D printers! £450 on ebay from China 
. Every teenage boys dream, just print up your ideal woman :_P
CRUSTY - 11-12-2017 at 10:06
I'm tempted to calculate the effective mass wasted via neutron radiation, but at the same time that sounds like it wouldn't be fun at all.
elementcollector1 - 11-12-2017 at 10:15
I've often wondered if replication might be made a little easier by using an existing feedstock instead of relying on strictly fusion. Something
heavy, like lead or uranium, that can contribute a lot of protons per unit mass. Still, that leaves the problem of figuring out all the right decay
chains that would lead you to the atom you want... and then getting rid of the waste!
aga - 11-12-2017 at 12:25
Kirk: "Computer. I only have carrots, a frozen chicken and some potatoes. I want roast chicken with fondant carrots and roast potatoes for dinner."
Computer: "Computing ... (many flashing lights and beeping) ... Insufficient data."
[Edited on 11-12-2017 by aga]
Chemvironment - 11-12-2017 at 12:34
I would guess that biological matter will be first (already is to some degree) to resemble replication. Growing things really fast will be much easier
than matter replication and would achieve the same goals essentially. At least that's where my thoughts took me before my first cup of coffee this
morning. I realize didn't answer any of your questions and was probably no help lol. I apologize.
[Edited on 11-12-2017 by Chemvironment]
NEMO-Chemistry - 11-12-2017 at 14:28
Didnt star trek invent the mobile phone 
?
XeonTheMGPony - 11-12-2017 at 16:26
in startreck it is direct energy to mass conversion, theoretically doable as we have don the revers quite allot all ready.
I thought I once read a paper where a group figured out a possible way to do as such short of a nuke but at that point they could only do one atom.
karlos³ - 12-12-2017 at 14:34
You mean the teleportation of a single, what was it, a photon?
Which hasn´t really much to do with the topic of matter replication, since this is a quantum effect, AFAIK quantum information can´t be duplicated.
Which would apply to MrHomeScientists posts, the transported matter with all his graininess on molecular level, just a whole lot of information.
Not sure if I´m right with that, but it would probably not make much of a difference if the matter is sent or destroyed, this quantum state
information is identical to the original, but not out of the original matter, so by definition a new person, same quantum state graininess but made
from different matter. Still the same thing or person though.
(Notice: "knowledge" acquired from reading hard sci-fi.. so may not be accurate at all, especially the part about quantum information being
replicated)
But seriously, mini-tweezers using nanobots?!? 
Molecular assemblers, it´s one of my greatest fears that physicists create something capable of this....
it would make every chemists, especially those doing small-scale bench work, unemployed over night!
Why pay a human chemists, with all the errors possible and cost involved, when those assembler thingies would just need the raw elements and manually
construct the wanted molecules from this...
Molecular assembling machines are a threat to our profession! (Or great addition maybe.... we´ll see...).
I´m much more chilled with the biotech industry growing pure fruit flesh in giant vats, even if this means the solid blocks of fruit mass have to be
manipulated mechanical to attain a natural look...
Example: scrape peach mass in halves, inside scrape another one, for the kernel who never existed... or strawberries, a biotech thriller I read
mentioned that the missing kernels were missed by the user, so they added some small grass seeds to the vat-grown fruit-flesh for customer
acceptance....
I would also prefer to have flesh grown without all the internal stuff, the thinking parts and such, what can´t be eaten, which is hopefully
something we´ve reached sooner than later.
This wouldn´t be a replicator of course, but could be an early source for the raw materials to replicate something out of.