@InvaderGzim it's not an idea. It's an observation. It's what all our telescopes - visual, x-ray, infrared and radio - have shown us. We don't understand it. Our bodies evolved in the 5%. We cannot directly sense the rest. But some of our telescopes can "see" it's affects on our 5% - what you call real matter. But it's all real. We can't see IR or UV light, or x-rays, but they exist. We feel IR as heat. UV burns our skin. X-rays can kill us. 150 years ago no one knew that. Now we do. Progress.