Solutions to the Fermi Paradox
My personal guess as to the solution of the Fermi "paradox" (not really a paradox) is fairly boring: 1. Space travel is virtually impossible. This is really the main reason. The Tsolkovsky Rocket Equation is a harsh taskmaster. This shows how hard it is to get out of a planet's gravity well: you need to burn fuel to launch yourself. But the more fuel you have, the heavier your craft is, thus the more fuel you need. The expansion is logarithmic, and it implies that the expense of even lifting a small number of people into orbit is enormous. And then, once you're up there, out of the atmosphere, beyond the magnetosphere, then you have real problems: space is trying to kill you. The radiation up there is extremely unhealthy. And the faster your spaceship moves, the more problems you have. If your ship can move close to the speed of light, then, relativistically, there will be particles whizzing into the front of your ship at close to t...