论文标题
$ su（2）$ yang-mills-higgs型号中本地量规不变的复合运算符的光谱特性
Spectral properties of local gauge invariant composite operators in the $SU(2)$ Yang--Mills--Higgs model
论文作者
论文摘要
在$ su（2）$ yang-mills--higgs模型中研究了一组本地量规（BRST）不变的复合算子的光谱特性，该模型在基本表示中具有单个Higgs字段，并在“ T HOOFT $ r_POR_配码”中量化。可以将这些操作员视为该理论基本领域的BRST不变版本，Higgs和Gauge领域，它们与它们共享一个独立的极点质量。 BRST不变式复合算子和基本场及其光谱函数的两点相关函数均以一环阶进行研究。结果表明，基本领域的光谱函数遭受了量规参数$ξ$的强大非物理依赖性，甚至可以表现出违反阳性的行为。相比之下，BRST不变的本地操作员表现出明确的正谱密度。
The spectral properties of a set of local gauge (BRST) invariant composite operators are investigated in the $SU(2)$ Yang--Mills--Higgs model with a single Higgs field in the fundamental representation, quantized in the 't Hooft $R_ξ$-gauge. These operators can be thought of as a BRST invariant version of the elementary fields of the theory, the Higgs and gauge fields, with which they share a gauge independent pole mass. The two-point correlation functions of both BRST invariant composite operators and elementary fields, as well as their spectral functions, are investigated at one-loop order. It is shown that the spectral functions of the elementary fields suffer from a strong unphysical dependence from the gauge parameter $ξ$, and can even exhibit positivity violating behaviour. In contrast, the BRST invariant local operators exhibit a well defined positive spectral density.
