The ModMax model of nonlinear electrodynamics (NED) is investigated in the absence of the linear term. The linear term is itself a ModMax model, however, the nonlinear term is not. First, in (3+1)-dimensional Minkowski spacetime, we introduce the electromagnetic theory in this NED model. We find the vacuum electric permittivity and magnetic permeability which both are in tensor form. This shows that the propagation of the speed of the electromagnetic wave depends on the direction. Finally, we couple our NED Lagrangian density minimally with the standard gravity and find a dyonic black hole solution.

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不含线性项的非线性电动力学 ModMax 模型

在没有线性项的情况下研究了非线性电动力学 (NED) 的 ModMax 模型。线性项本身是 ModMax 模型，但非线性项不是。首先，在（3+1）维的闵可夫斯基时空，我们介绍了这个NED模型中的电磁理论。我们发现真空介电常数和磁导率都是张量形式。由此可见，电磁波的传播速度取决于方向。最后，我们将我们的 NED 拉格朗日密度与标准引力最低限度地耦合起来，并找到一个动力学黑洞解决方案。