Veneziano amplitude

In theoretical physics, the Veneziano amplitude refers to the discovery made in 1968 by Italian theoretical physicist Gabriele Veneziano that the Euler beta function, when interpreted as a scattering amplitude, has many of the features needed to explain the physical properties of strongly interacting mesons, such as symmetry and duality.^[1] Conformal symmetry was soon discovered. The formula is the following:

${\displaystyle {\frac {\Gamma (-1+{\frac {1}{2}}(k_{1}+k_{2})^{2})\Gamma (-1+{\frac {1}{2}}(k_{2}+k_{3})^{2})}{\Gamma (-2+{\frac {1}{2}}((k_{1}+k_{2})^{2}+(k_{2}+k_{3})^{2}))}}}$ .

k_n is a vector (such as a four-vector) referring to the momentum of the n^th particle. Γ is the gamma function.

This discovery can be considered the birth of string theory,^[2] as the discovery and invention of string theory came about as a search for a physical model which would give rise to such a scattering amplitude. 

This article uses material from the Wikipedia article  Metasyntactic variable, which is released under the  Creative Commons Attribution-ShareAlike 3.0 Unported License.