Taylor state

In plasma physics, a Taylor state is the minimum energy state of a plasma satisfying the constraint of conserving magnetic helicity.

Consider a closed, simply-connected, flux-conserving, perfectly conducting surface ${\displaystyle S}$ surrounding a plasma with negligible thermal energy (${\displaystyle \beta \rightarrow 0}$).

Since ${\displaystyle {\vec {B}}\cdot {\vec {ds}}=0}$ on ${\displaystyle S}$. This implies that ${\displaystyle {\vec {A}}_{||}=0}$.

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