👉 The term "grein" is a term used in the field of physics, specifically in the context of quantum mechanics. It refers to the concept that particles (such as electrons) can be described by wave-like phenomena, rather than by classical particles like photons or waves. In classical physics, objects are described using particles such as photons and light waves. These particles have definite properties and follow a mathematical law. However, in quantum mechanics, particles are described using wave-like phenomena, which can exhibit properties