When quantum particles were studied, it was discovered that we could know where they were OR how fast they were going, but not both at the same time. This is known as the Uncertainty Principle. It means that we can’t know everything in the universe. So much for the know-it-alls!
Einstein discovered that light is a particle. However, when we shine light through a prism, the light waves are separated into rainbow colors. Each color is a frequency of the light wave. So light and other quantum particles are both a particle and a wave!
Einstein could not accept this particle/wave duality of quantum particles so he devised a thought experiment to disprove it. This led to the discovery of “entanglement” which says you can’t talk about some particles without reference to another particle. When you touch one particle it immediately affects the other entangled particle. So what you do affects more than you know! What do you do that affects others?