A Gaussian fixed point is a
fixed point of the
renormalization group flow
In theoretical physics, the term renormalization group (RG) refers to a formal apparatus that allows systematic investigation of the changes of a physical system as viewed at different scales. In particle physics, it reflects the changes in the ...
which is noninteracting in the sense that it is described by a
free field theory.
The word Gaussian comes from the fact that the probability distribution is Gaussian at the Gaussian fixed point. This means that Gaussian fixed points are exactly solvable (
trivially solvable in fact). Slight deviations from the Gaussian fixed point can be described by perturbation theory.
See also
*
UV fixed point
In a quantum field theory, one may calculate an effective or running coupling constant that defines the coupling of the theory measured at a given momentum scale. One example of such a coupling constant is the electric charge.
In approximate cal ...
*
IR fixed point
*
Quantum triviality
In a quantum field theory, charge screening can restrict the value of the observable "renormalized" charge of a classical theory. If
the only resulting value of the renormalized charge is zero, the theory is said to be "trivial" or noninteracting. ...
References
Renormalization group
Statistical mechanics
{{statisticalmechanics-stub