I am sure you all have heard of Einstein. He is the first person who used the expression “quantum” which means the discontinuity of light, in his photoelectric effect experiment1)
. Through this experiment, he realized that light can be regarded as particles and called these particles “light quantum”. The atom, the basic unit of matter, also consists of quantum which actually is both protons and electrons. Those particles are very small (nanoscale, 10-9
m), so if you focus on those kinds of small particles then that would be considered in the realm of quantum nanoscience. In this scale of the world where quantum exists, even energy and space are “quantized”, which means being discontinuous like quantum.