The aim of this paper is to find conformal vector fields (CVFs) for some vacuum classes of the pp-waves space-times in the ghost free infinite derivative gravity (IDG). In order to find the CVFs of the above-mentioned space-times in the IDG, first, we deduce various classes of solutions by employing a classification procedure that in turn leads towards 10 cases. By reviewing each case thoroughly by direct integration technique, we find that there exists only one case for which the space-time admits proper CVFs whereas in rest of the cases, the space-time either becomes flat or it admits homothetic vector fields (HVFs) or Killing vector fields (KVFs). The overall dimension of CVFs for the pp-waves space-times in the IDG has turned out to be one, two, seven or fifteen.

中文翻译：

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无鬼无限导数重力中某些真空类 pp 波时空的共形矢量场

本文的目的是为无鬼无限导数重力 (IDG) 中的 pp 波时空的某些真空类找到共形矢量场 (CVF)。为了在 IDG 中找到上述时空的 CVF，首先，我们通过采用分类程序推导出各种类别的解决方案，进而导致 10 个案例。通过直接积分技术彻底审查每个案例，我们发现只有一个案例时空允许适当的 CVF，而在其余案例中，时空要么变得平坦，要么允许相似向量场 (HVF)或杀死向量场 (KVF)。IDG 中 pp 波时空的 CVF 的整体维度已证明是一、二、七或十五。