Science’s understanding of the universe is that most of it is totally invisible. There have been two popular theories of what this stuff might be (named with typical physicist dork-wordplay): tiny WIMPs (Weakly Interacting Massive Particles, infinitesimal particles everywhere that we just can’t detect) versus enormous MACHOs (MAssive Compact Halo Objects — planetoids, dead stars, big stuff out there that doesn’t emit light). Scientific understanding is pointing more and more towards the WIMP theory… problem is, we haven’t ever seen any.

Today, physicists announced that they found evidence of WIMPs for the first time. In an experiment in Antarctica, they detected electrons with the right amount of energy that would have been created by a WIMP crashing into a… normal thing.

Why do we care about what we can’t see? For one reason… most of the universe appears to be made up of it:

The standard model of the way the Universe was created hangs together pretty well if dark matter – about which we know, like, next to nothing – is included. If there’s no such thing as dark matter… well, what we know explains 4% of the Universe. Humbling.

If the experiment did actually find evidence of dark matter, it’s a big boost to the idea that there are many other “compact” dimensions in addition to the four we all know and love. The mathematics used in superstring theory, for example, needs at least 10 dimensions to begin to work out. Modern physics is based on two big theories – general relativity and quantum mechanics – that don’t fit together. As superstrings are one of the leading contenders to make the two pieces fit, this discovery could be big news.