Sci-fi enthusiasts note that unknown technologies may develop, such as the ability to warp the fabric of spacetime or to travel through a wormhole. But again, these suggestions are purely speculative. Other than some fancy math that suggests such maneuvers could theoretically be possible, we have no idea if either can actually happen. Just because unicorns and mermaids are theoretically possible does not mean that they exist.

What about black holes? Perhaps we could dive into one and pop out somewhere else. For the sake of argument, let’s say that we know that is absolutely true. The trouble is that the closest black hole to Earth that we know of is 1,500 light-years away.

Putting all this together, the sobering conclusion is that it does not matter if intelligent alien life exists elsewhere in the universe. We will never find them, and they will never find us. In other words, we are effectively alone in the universe.