Scattering amplitudes are mathematical quantities used to describe the behavior of particles in scattering processes. Scattering occurs when particles interact with each other, typically through forces or fields, and change their direction or momentum as a result of the interaction.
In quantum field theory, which describes the behavior of particles and their interactions, scattering amplitudes provide a way to calculate the probabilities of different scattering outcomes. They quantify the likelihood of particles scattering from initial states to final states with specific momenta and energies.
Scattering amplitudes are typically calculated using mathematical techniques such as Feynman diagrams, perturbation theory, or other advanced methods like string theory or the bootstrap program. These calculations involve taking into account the properties of the particles involved, their interactions, and the conservation laws of energy, momentum, and other relevant quantities.
Scattering amplitudes are essential in particle physics, where they are used to predict and analyze the outcomes of high-energy experiments, such as those conducted at particle accelerators. They provide crucial information about the fundamental properties of particles and the underlying forces and interactions in the universe.