Instanton fluid
Encyclopedia
In quantum chromodynamics
, the instanton fluid model is a model of Wick rotated Euclidean quantum chromodynamics. If we examine the path integral
of the action, we find that it has infinitely many local minima
, corresponding to varying instanton
numbers. It turns out that the dominant contribution to the path integral comes from configurations with consisting of a pool of instantons and antiinstantons. The exponential suppression coming from the increased action is compensated by the increased phase space factor coming from all the instantons. In other words, the "Euclidean" free energy is minimized by a pool of instantons.
We also know that in the presence of an instanton, left-handed quarks of each flavor will be produced and right-handed quarks annihilated. This evidently will have consequences to the chiral dynamics of the theory.
Quantum chromodynamics
In theoretical physics, quantum chromodynamics is a theory of the strong interaction , a fundamental force describing the interactions of the quarks and gluons making up hadrons . It is the study of the SU Yang–Mills theory of color-charged fermions...
, the instanton fluid model is a model of Wick rotated Euclidean quantum chromodynamics. If we examine the path integral
Path integral formulation
The path integral formulation of quantum mechanics is a description of quantum theory which generalizes the action principle of classical mechanics...
of the action, we find that it has infinitely many local minima
Maxima and minima
In mathematics, the maximum and minimum of a function, known collectively as extrema , are the largest and smallest value that the function takes at a point either within a given neighborhood or on the function domain in its entirety .More generally, the...
, corresponding to varying instanton
Instanton
An instanton is a notion appearing in theoretical and mathematical physics. Mathematically, a Yang–Mills instanton is a self-dual or anti-self-dual connection in a principal bundle over a four-dimensional Riemannian manifold that plays the role of physical space-time in non-abelian gauge theory...
numbers. It turns out that the dominant contribution to the path integral comes from configurations with consisting of a pool of instantons and antiinstantons. The exponential suppression coming from the increased action is compensated by the increased phase space factor coming from all the instantons. In other words, the "Euclidean" free energy is minimized by a pool of instantons.
We also know that in the presence of an instanton, left-handed quarks of each flavor will be produced and right-handed quarks annihilated. This evidently will have consequences to the chiral dynamics of the theory.