Scientific terminology informal or non-technical English, to say "strictly speaking" for "sensu stricto" and "broadly speaking" and so on is valid. Even in formal writing, there is no formal requirement to use the Latin terms rather than the vernacular. Valid reasons for using these Latin or partly Latin expressions are not points of pretentiousness; they include: A good example is the word "laser", an acronym for "Light Amplification by Stimulated Emission of Radiation", and therefore all its letters should be capitalized. However, because of frequent use, this acronym became a neologism, i.e., it has integrated into English and most other languages. Consequently,
Stimulated emission difference in energies between the two states as a photon. The photon will have frequency "ν" and energy "hν", given by: where "h" is Planck's constant. Alternatively, if the excited-state atom is perturbed by an electric field of frequency "ν", it may emit an additional photon of the same frequency and in phase, thus augmenting the external field, leaving the atom in the lower energy state. This process is known as stimulated emission. In a group of such atoms, if the number of atoms in the excited state is given by "N", the rate at which stimulated emission occurs is