The Science of Doctor Who: s01e09-10, “The Empty Child / The Doctor Dances”
Nanobots, nanites, nanogenes: these are all science-fiction terms for microscopic robots that can repair or create materials one molecule (or atom) at a time. We dream of building super-strong metals from base elements, or sending them into our bodies to remover cancers or repair damage. We’ve already made a few very crude examples, ver basic mechanisms only a few molecules in size!
But some science-fiction writers use this as a synonym for “magic” when they’re in a hurry; though this is an excellent Who story – one of my favorite tales of the Ninth Doctor – Moffat succumbed to the temptation. In seconds, these tiny little robots scan an unknown life form, determine how it is put together, determine damage, and repair it. It’s hard to imagine how they’re doing this. We can see no visible power source or external computer support, and a nanobot has to be a *very* simple device, by basic laws of physics. For example, a real cancer-killer nanite wouldn’t be complicated enough to do much more than blindly swim through the body until it bumped into something it could recognize as cancer.
If we grant that the nanogenes are smart enough to scan a body and do major conversion work with no power or raw materials other than the body at hand, we get other problems. How were they dumb enough to think the little boy’s gas mask was his body, but not his clothing? (Would have been great to see everyone with the nanogene infection forced into short trousers.) Also, the little bots are dumb about the gas mask but smart enough to recognize different genders, heights, weights, hair colors; that’s some odd programming. Must still be in beta.
Somehow they work, though. And the Doctor literally hand waves the job of reprogramming them to repair everyone properly. Now we bump into a common sci-fi peeve of mine: where did the reprogrammed nanogenes get the information to put everyone back together again properly (again with all the different genders, heights, weights, and hair colors)? If the answer is, “they extrapolated everyone’s DNA”, well that’s great. If they could do that, the nanogenes probably should have been doing that when they scanned the little boy in the first place? I’d also love to know how the critters were able to destroy everyone’s minds, but completely restore them afterward. It would be like smashing your hard drive, buying a new one, and expecting all your data to be on it. Doctor Crusher liked to ignore this problem on the Enterprise-D, too.
One last nit to pick: I’ve lived through my body trying to rebuild just a couple of smashed bones. The physiological stress of the conversion to gas-mask zombie in the first place would kill you. Between the excrutiating pain, and the sudden changes to your biology, your body wouldn’t handle the shock. The conversion process would make more sense if everyone’s body went into a coma for weeks before emerging as a gas-masked little boy, but I’ll concede that would be lousy TV.
Next time: I’m afraid I’ll have to blow up the Earth. It obstructs my view of Raxacoricofallapatorious.
Tags: doctor who, science, tv, who science
