Atom

The atom (Ancient Greek ἄτομος, átomos, "uncuttable") is a basic unit of matter from which all elements and molecules are made. It consists of a dense, central nucleus made from protons and neutrons, with electron clouds around it.

Electron Cloud
Around the nucleus, there are electrons in well-defined orbits. An electron with higher energy appears in an orbit further away from the nucleus. When an electron emits energy as a photon, it jumps to a lower orbit. The electrons inside atoms have a constant rotational speed, noted X, and so they move faster when in higher orbits.

According to pilitron physics, the speed of an electron inside an atom is given by:


 * $$v = 2\alpha roc \,\!$$

where:
 *  = alpha constant
 * r = radius of the lowest orbit (constant value)
 * o = orbit number (1 = lowest orbit)
 * c = speed of light

An electron can only exist in an orbit lower than orbit L, the limit orbit:


 * $$L = \frac{1}{2\alpha r}$$

This is because an electron in orbit L would have to travel at the speed of light.