Quantum Realm
The quantum realm in physics is the scale at which quantum mechanical effects become important when studied as an isolated system., respectively. While originating on the nanometer scale, such effects can operate on a macro level, generating some paradoxes like in the Schrödinger's cat experiment. Two classical examples are quantum tunneling and the double-slit experiment. Most fundamental processes in molecular electronics, organic electronics, and organic semiconductors also originate in the quantum realm. The quantum realm can also sometimes involve actions at long distances. A well-known example is David Bohm's version of the famous thought experiment that Albert Einstein, Boris Podolsky, and Nathan Rosen proposed in 1935, the EPR paradox. Pairs of particles are emitted from a source in the so-called spin singlet state and rush in opposite directions.
