Speculative

By the end of this century, and before I am dead, we will learn that there are other civilizations in our galaxy. They will be busy being industrious, sending communications back and forth to one another, and they won't have noticed us yet. The Milky Way Galaxy will turn out to be a bustling place, full of life. It is vast, and mostly empty, but then so is the Pacific Ocean, and yet we consider the Pacific the highway of the world.

We should cherish these times while we still have them. We should cherish the ability to look up at the sky and wonder and simply not know what sorts of things are out there. Because soon we will know, and it will be exciting, but it will also be scary, because the things out there are extremely powerful.

We will discover amazingly advanced civilizations that will boggle our imaginations. However, we will be impotent to communicate with them, and we will only be able to glean what information we can from their transmissions. They may have perfected encription and compression to the point where we cannot distinguish their communications from meaningless noise, and the only evidence of extreme intelligence will be the artificiality of the signal.

We will discover that our world is much larger than it ever has been. As big as our planet is, our galaxy is so much bigger, and so much more inaccessible. We will be able to witness industry on a galactic scale, but we will be unable to participate. We will be like the Pacific Islanders building airstrips and artificial airplanes out of bamboo in the hopes of attracting the far-off flying planes. We will have our own mathematical cargo cults, the smartest among us will only build crude decoys that we will broadcast as the weakest of signals, in the hopes that a passing extraterrestrial freighter might stop and leave us some precious cargo.

What manner of cargo? My point is of course that we cannot know what the universe has in store, and we might never know. We will know by the end of this century that there are others out there, but it will be another millenium before we can send and receive signals. It's the beauty of this century that we are allowed to dream of what may come, with no actual knowledge, and never again will we be in this position.

So what manner of cargo? Well, first of all, we'll be looking for encription codes to unlock the secrets of the communications, not meant for us. After encription codes, we'll be looking for secrets of physics and the universe. Perhaps we will learn that there is nothing more to learn, that indeed the speed of light is a fundamental limit, that no new subatomic particles are available to discovery. Perhaps we will learn that the galactic overlords themselves are conducting a SETI project over millions of years to search for, and communicate with intelligences in other galaxies.

The kind of cargo I will be looking for will be the physical specifications for building things like quantum computers, and engineering designs for building spaceports, space elevators, and spaceborn shipyards. Perhaps instructions sent to automated facilities, which we can intercept, interpret, and reproduce. Perhaps there will be instructions for fusing hydrogen into any element desirable, simply, easily, and cheaply. Of course, all of these technologies, even with knowing how they can be done, will cost so much money to implement, requiring interplanetary infrastructure, that we will take centuries to reproduce them, if we can at all. Atomic fusion reactors built in the spaces between planets and asteroids, require thousands, perhaps millions of miles of space.

Or maybe there will be some kind of physical cargo. Interstellar freight lines, broken into asteroids, summing to masses greater than Jupiter, space trains millions of miles in length, travelling in convoys across the galaxy. Iron, gold, silver, titanium, platinum. Shooting in streams of matter from one end of the galaxy to the other. Just one of these asteroids worth more than the combined wealth of our entire planet.

Or perhaps supercomputer components, built at the quantum level, and integrated with software the likes which we cannot even imagine.

Or perhaps interstellar cargo will simply be streams of hydrogen atoms, or photons themselves. If technology is physically possible to transform matter and energy, perhaps the cargo lines of the galaxy are intense beams of light. If matter can be transformed into light and back again, then it should be most efficient to transport all cargo as photons. In that case, we're fortunate that we haven't been struck by such beams already. Unless they're part of what we have been seeing as the spectrum of cosmic rays, they've been passing through us this whole time, and we don't know how to receive them.

So we should count ourselves lucky to live in an innocent age. We don't have to be jaded about the industry of the galaxy. We don't have to worry about the stability of the galaxy because of interstellar pollution.