We’re Probably Not Alone

Youtube’s recommendations to me lately have been pretty scientific. I’ve been watching a lot about stars, planets and black holes on one end of the scale, and videos about quantum mechanics and subatomic particles on the other. Scattered in my recommendations though are the odd video about life outside our solar system. You know, aliens and stuff. Things that are mostly just speculation.

Really, when you think about it, there are a lot of stars with a lot of planets orbiting them. Scientists have been finding a lot of Earth-like planets, although many have been a lot bigger than Earth. Whether there is life on any of the planets we’ve discovered, we don’t really know. The question to there being life outside of the solar system is currently unanswerable.

Basically, what I’m trying to say is that we’re probably not alone out here. The numbers suggest that there must be other planets with life on it like ours, it’s the law of large numbers. Heck, there’s so many potential Earth-like planets that somewhere out there, there has to be some alien writing articles for their blog, the Daily Fups, also wondering if life exists out there. That’s how vast the universe is, that we could potentially have copies of ourselves. The universe is so insanely vast that there HAS to be some life out there.

The question is, however, where IS all this life? Why haven’t we seen aliens or anything like that? This problem is called the Fermi Paradox. A massive discrepancy between what numbers suggest and the fact that we’ve found nothing. There are all sorts of theories, like us being the first race to leave their planet, or that there are predatory races that prey on people like us, or that there is a Great Filter, a series of trials or steps that life has has to pass to even get as far as we are now.

But in my opinion, the real reason is that no one can see us, because of light. You see, when looking into the sky, we are also looking into the past. We need light in order to see, but light’s speed is limited. It takes time for the light from a distant star to reach our eyes or telescopes. So when we, for example, look towards our nearest stellar neighbours, the stars of Alpha Centurai, we see them as they were 4.2 light years ago. Because it takes 4.2 years for the light from those stars to reach us here on earth. Essentially, we are looking back in time.

This applies to everything we see. If there was an Earth-like planet 10 light years away and something on it looked in our direction, it would see us as we were in 2013, 10 years ago. And the further the distance, the further we go back in time. An Earth-like planet 100 light years away would see us 100 years into our past, between the world wars. 1000 light years away and we’re back in medieval times. In fact, because light travels at a set speed in a vacuum, the furthest things we can see are also the furthest back in time. The universe is believed to be 13.7 billion years old, and we can’t see anything past that because light just hasn’t traveled fast enough yet.

Of course, the lack of proof for life out there almost certainly has multiple reasons. After all, it is a big universe, and the speed of light is finite. But I believe that the biggest reason is simply because we’re looking back in time, into the past, and so is everything else.

At the end of the day, we’re probably not alone. But we’re just too far away to be contacted by anyone, due to how light travels.