We outline the modifications in the numerical Boltzmann code Cosmic Linear Anisotropy Solving System (CLASS) in order to include extra inflationary fields. The functioning of the code is first described, how and where modifications are meant to be done are later explained. In the present study, we focus on the modifications needed for the implementation of a two‐field inflationary model, with canonical kinetic terms and a polynomial potential with no cross terms, presenting preliminary results for the effect of the second field on the spectra. The adaptability of the code is exploited, making use of the classes and structures of C and the generic Runge–Kutta integration tool provided by the program.

中文翻译：

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宇宙线性各向异性求解系统的两场膨胀实现

为了概述额外的膨胀场，我们概述了数值Boltzmann代码宇宙线性各向异性求解系统（CLASS）中的修改。首先描述了代码的功能，随后将解释如何以及在何处进行修改。在本研究中，我们着重于实现具有标准动力学项和无交叉项的多项式势的两场通货膨胀模型的实施所需的修改，从而提供了第二场对光谱的影响的初步结果。利用C的类和结构以及程序提供的通用Runge-Kutta集成工具来开发代码的适应性。