This Is What Extraterrestrial Life Would Look Like

2. All Around Us (In A Different Dimension)

https://www.youtube.com/watch?v=iiWKq57uAlk We spend most of our time pointing our telescopes at dim, distant objects in the sky, in the hope that one day we'll see a little alien waving back (that's how astronomy works, right?) However, there is a theory floating around that the aliens could be all around us, just in a different dimension. This is also another contender for the "reasons why we haven't been contacted" category, as it's pretty difficult to communicate across dimensions. The interdimensional hypothesis is commonly used by Ufologists as a way of explaining how alien spacecraft can appear to wink in and out of existence (don't let that put you off though). To consider another dimension, you have to think about moving in another direction in addition to up, down, left and right. It's quite difficult to get your head around what a four-dimensional projection into three-dimensional space would look like, you would essentially see a three-dimensional cross section of it moving and shifting through space. The best way to think about it is to scale it back to the second and third dimensions and imagine what it would look like to a two-dimensional being if you put your hand through the 2D plane that they live on. The venerable Carl Sagan explains it in the video above. The interdimensional hypothesis gets a bit muddied by everybody from ghost hunters to theoretical physicists using it to try to understand the universe. Could it be that the aliens are all throwing big, four-dimensional parties without us?