Atomic physics although they could be described and classified by their properties (in bulk). The invention of the periodic system of elements by Mendeleev was another great step forward. The true beginning of atomic physics is marked by the discovery of spectral lines and attempts to describe the phenomenon, most notably by Joseph von Fraunhofer. The study of these lines led to the Bohr atom model and to the birth of quantum mechanics. In seeking to explain atomic spectra an entirely new mathematical model of matter was revealed. As far as atoms and their electron shells were concerned, not only did this
Branches of physics This theory is currently under developmental stage. Optics is the study of light, and the instruments created to use or detect it (i.e. telescopes, spectrometers, etc.). Atomic physics, molecular physics, and optical physics are each individual sub-fields of AMO that study the physical properties of the atom, molecules, and light, respectively. The study of the physical properties of matter in a condensed phase. Particle physics studies the nature of particles, while nuclear physics studies the atomic nuclei. Cosmology studies how the universe came to be, and its eventual fate. It is studied by physicists and astrophysicists. To the interdisciplinary fields,