Concept

Auxiliary field

Summary
In physics, and especially quantum field theory, an auxiliary field is one whose equations of motion admit a single solution. Therefore, the Lagrangian describing such a field A contains an algebraic quadratic term and an arbitrary linear term, while it contains no kinetic terms (derivatives of the field): :\mathcal{L}_\text{aux} = \frac{1}{2}(A, A) + (f(\varphi), A). The equation of motion for A is :A(\varphi) = -f(\varphi), and the Lagrangian becomes :\mathcal{L}_\text{aux} = -\frac{1}{2}(f(\varphi), f(\varphi)). Auxiliary fields generally do not propagate, and hence the content of any theory can remain unchanged in many circumstances by adding such fields by hand. If we have an initial Lagrangian \mathcal{L}_0 describing a field \varphi, then the Lagrangian describing both fields is :\mathcal{L} = \mathcal{L}0(\varphi) + \mathcal{L}\text{aux} = \mathcal{L}_0(\varphi) - \frac{1}{
About this result
This page is automatically generated and may contain information that is not correct, complete, up-to-date, or relevant to your search query. The same applies to every other page on this website. Please make sure to verify the information with EPFL's official sources.
Related publications

Loading

Related people

Loading

Related units

Loading

Related concepts

Loading

Related courses

Loading

Related lectures

Loading