If there were creatures on other planets that were much more advanced that we are -- a very familiar idea in the 19^th century -- they might not even consider us intelligent, much less civilized. Maybe they consider us like domestic animals on a far … or like exhibits in a zoo. Maybe they own us, tend us secretly, cull out fat specimens and eat them. Lots of good stories have been written about this, and early 20^th century pseudoscientist Charles Fort got a number of books out of the theme. But alas, there is no evidence whatsoever of visitors from other planets, advanced or otherwise, benign or malevolent. The other problem is why visitors from other planets should have any attitude toward us at all, pro or con. What's your attitude toward the squirrels in your back yard? Or the ants? Or the crickets? If they don't bother you, you probably don't even notice -- much less bother -- them. And they're right in your backyard, not 100 light years away.

Early 20^th century science fiction writers did not add that many new themes. The four most often encountered are:

THE ATOM AS A LITTLE SOLAR SYSTEM … OR, OUR SOLAR SYSTEM AS A GIGANTIC ATOM

This is based on a public misunderstanding of very early, primitive work on the structure of the atom. In Bohr's early, pre-quantum model, electrons orbit the nucleus of the atom vaguely like planets orbit the sun. But this picture of the atom is not correct. An atom is absolutely nothing like a solar system; electrons are absolutely nothing like planets. The classical physical laws obeyed by planets are totally different from the quantum-physical laws obeyed by atoms and their constituents. This is a classic instance of a completely false analogy.

MATTER TRANSMITTERS

I don't know who invented this concept, but it was probably Ralph Milne Farley in the 1920s with his RADIO MAN series. The idea is familiar from the later use in TV fantasy shows like STAR TREK. Somehow your body is scanned and recorded -- and in the process presumably destroyed. Then the information is transmitted some vast distance and the body reconstructed somehow from the information available, using raw materials lying around in the new location. That this is not just difficult but essentially impossible can easily be seen. There are about 10(28) atoms in a human being. Suppose that the position of each atom could be measured in about the time it takes light to cross an atom -- that is as fast as it could possibly be done, assuming the measuring device literally peels away the body and so is literally in contact with each atom it measures. The time for light to cross an atom is about 10-18 seconds. So to scan a human body would take about 10(28) x 10.18 sec or about 300 years! To reconstruct the body at the other end, again as fast as possible, would take the same length of time. Furthermore the reconstructed body would be just that … it would not be the original individual who was destroyed more that 6 centuries before, at the other end of the transmitter. Any activity of the brain that involves dynamic behavior -- steady currents, makes and breaks of contact, etc. -- would not get recorded. Only information stored in the form of specific molecules would get across. In short, the reconstructed body might have some of the memories of the original individual, but might not have all of his personality, training, etc. … or any of it.

SPACE WARP, HYPERSPACE, OR STAR DRIVE

Interstellar travel is not too practical a prospect, because to travel any significant fraction of the radius of our own galaxy would require thousands of years travelling as fast as one can go, just under the speed of light. Science fiction writers have invented various totally imaginary ways to get around this problem so that they can use the usual cowboys and Indians plots. You can't rescue Princes Layya from Barf Tater if it takes 300 years to find out he has her and 400 years to get to where she's held prisoner. Layya and Barf would presumably be long gone by the time Luke Starkicker got on the scene with his faithful robot companion DO-2-U-2. Apparently the first writer to consciously avoid this problem was E. E. ("Doc") Smith, back in the 1920s -- probably because he was also the first writer to do much with the concept of interstellar travel, in his famous Skylark and Lensman series. "Doc" solved the problem by asserting that his space ships could be made inertialess -- and thus (according to "Doc") could in their inertialess state travel effortlessly at huge multiples of the speed of light. In fact, however, an object without inertial mass (for instance a photon or neutrino) must travel at precisely the speed of light, neither faster nor slower, at all times. "Doc," for purposes of his stories, was also unclear about how one "goes inertialess," since inertia is an intrinsic property of matter.