No matter how hard physicists probe, they still puzzle over this, the universe's deepest secret
If you’re interested in the smallest things known to scientists, there’s something you should know. They are extraordinarily ill-behaved. But that’s to be expected. Their home is the quantum world.
Full article in Science News For Students: https://www.sciencenewsforstudents.org/article/quantum-world-mind-bogglingly-weird