Much has been written as to problems of
physics for the common
science fiction themes of
time travel,
teleportation and
faster than light travel. But there is another science fiction motif which -- although less popular, assuredly, and more often played for comedy -- which is almost as problematic. It is the shrinking of a human, or several, to the size of an
insect or a
cell or a few
molecules.
This theme was exploited seriously in
The Fantastic Voyage, with a shrunken ship traveling inside a human body, and
The Incredible Shrinking Man, with a man who is eventually reduced to the size where battle with a
spider means taking on a relative
behemoth. These, again, were taken off for laughs in movies like
Innerspace,
Honey, I Shrunk the Kids,
The Incredible Shrinking Woman, and a lengthy sequence of
My Favorite Martian, not to mention innumerable children's
cartoons. In most every instance where such a theme is promoted, the actual event of the shrinking is done via some sort of ray, or device, or introduction of some sort of chemical.
There are a few ways, confessedly highly imperfect, by which this sort of
transformation might theoretically be accomplished:
One method would be by reducing the
distance between subatomic particles, so that the molecular composition of the shrunken person remains exactly the same to the last detail. This is not entirely implausible -- there being an overwhelming preponderance of empty space between these particles as things stand, so there surely being much room for decreasing of same. But, there are some distinct problems with this approach, the chief among them being that it would increase the density of the person effected, but for maintaining their molecular consistency, they would maintain the same
weight and, perhaps more intriguingly, the same
strength. Considering the fact that a typical hundred and sixty pound man, shrunk to a hundred and sixty pound
grain of sand-sized thing, would not fare well within the body of another, but would instead tear straight down through and out of it. And into the ground, and down until you hit rock. No amount of flailing and grasping would be of any use, the shrunken person's tiny arms slicing through so many particles like tiny
scalpels.
A second problem is one of
sustaining this situation. Perhaps a space could be created within which this effect could very temporarily be made to come about, and the atoms so condensed could be made to remain that way for a time. But in a person inside another person? Or even a person out in the world, locked in gladiatorial combat with legions of
dust mites and
spiders and
ants? Whatever force might be cause such a compression, assuming this feat did not kill the human upon whom it was attempted, could not permanently offend the
laws of nature. It is, in fact, highly unlikely that any form of subatomic
compression could be sustained but for a few minutes within a chamber especially designed to sustain this state of things within it.
Another method would be to reduce not only the distance between subatomic particles, but the size of all components, down to and including the subatomic particles themselves. Were this to conceivably be done in some localized sense, it would in theory reduce the mass of the subatomic particles themselves, and so alleviate the problem of a super-dense miniaturized person. But, the problem remains, and perhaps is even exacerbated, as to how such a person might be maintained in their shrunken status, and indeed how it could interact at all with the outside world. How could a person with shrunken atoms or shrunken subatomic particles breathe normal, unshrunken molecules of air? Eat unshrunken food? Wither the
waste,
solid,
liquid, and
gaseous, of such a person?
A method which would avoid atomic
mechanics would be simply reducing the number of cells in the body -- a method which would cause the receiver to lose weight, and strength, but would ultimately cause any person to lose any semblance of humanity far before they reached a size small enough to float harmlessly within the body of another. After all, how many cells can one lose and still be who one is, especially
brain cells? Surely shrinking a human by this method to a size smaller than the original brain of that person would do no more than
lobotomize and then
execute him.
Finally, the possible combination of the above -- reducing the distance between subatomic particles, the size of the particles themselves, and the number of cells -- seems primed to conflagrate the problems, instead of solving any of them.
A clever twist was taken in a
Futurama episode, where the characters were not actually shrunk at all, but were put in
remote control of tiny miniaturized versions of themselves. Future
surgeons may, along that same
vein (no
pun intended), someday experience the virtual effects of shrinking and journeying into a human body on a
mission of
healing by donning
virtual reality gear and taking control of a
nanobot making such a
trek.