A class of effective field theory called delta-theory, which improves ultraviolet divergences in quantum field theory, is considered. We focus on a scalar model with a quartic self-interaction term and construct the delta theory by applying the so-called delta prescription. We quantize the theory using field variables that diagonalize the Lagrangian, which include a standard scalar field and a ghost or negative norm state. As well known, the indefinite metric may lead to the loss of unitary of the [Formula: see text]-matrix. We study the optical theorem and check the validity of the cutting equations for three processes at one-loop order, and found suppressed violations of unitarity in the delta coupling parameter of the order of [Formula: see text].

中文翻译：

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λφ4 δ 理论中的光学定理和不定度量

考虑了一类称为δ-理论的有效场论，它改进了量子场论中的紫外发散。我们专注于具有四次自交互项的标量模型，并通过应用所谓的 delta 处方来构建 delta 理论。我们使用使拉格朗日对角化的场变量来量化该理论，其中包括标准标量场和鬼或负范数状态。众所周知，不确定的度量可能导致[公式：见文本]矩阵的单一性丢失。我们研究了光学定理并检查了单环阶三个过程的切割方程的有效性，并发现在[公式：见文本]阶的增量耦合参数中抑制了违反单一性。