Stability in the higher derivative Abelian gauge field theory

TL;DR

This paper derives conserved tensors in higher derivative Abelian gauge theories, demonstrating conditions under which the theory remains stable despite the unbounded canonical energy, by constructing bounded conserved quantities through parameter adjustments.

Contribution

It introduces a method to obtain bounded conserved tensors in higher derivative Maxwell theories, ensuring stability despite unbounded canonical energy.

Findings

Conserved tensors are derived from higher-order symmetries.

Certain parameter choices lead to bounded energy-momentum tensors.

The third-order case is analyzed for stability under various root decompositions.

Abstract

We present the derivation of conserved tensors associated to higher-order symmetries in the higher derivative Maxwell Abelian gauge field theories. In our model, the wave operator of the higher derived theory is a $n$-th order polynomial expressed in terms of the usual Maxwell operator. Any symmetry of the primary wave operator gives rise to a collection of independent higher-order symmetries of the field equations which thus leads to a series of independent conserved quantities of derived system. In particular, by the extension of Noether's theorem, the spacetime translation invariance of the Maxwell primary operator results in the series of conserved second-rank tensors which includes the standard canonical energy-momentum tensors. Although this canonical energy is unbounded from below, by introducing a set of parameters, the other conserved tensors in the series can be bounded which ensure the stability of the higher derivative dynamics. In addition, with the aid of auxiliary fields, we successfully obtain the relations between the roots decomposition of characteristic polynomial of the wave operator and the conserved energy-momentum tensors within the context of another equivalent lower-order representation. Under the certain conditions, the 00-component of the linear combination of these conserved quantities is bounded and by this reason, the original derived theory is considered stable. Finally, as an instructive example, we discuss the third-order derived system and analyze extensively the stabilities in different cases of roots decomposition.