A theory, originated in 1900 by the German physicist Max Planck, according to which emission and absorption of radiant energy are not continuous but take place in small finite amounts, or quanta.

[the ~] 【理】量子论(德国物理学家蒲郎克在1900年首创此说，谓辐射能的放射与融合，系不连续的，而在量子中发生)。