In this article, aspects of quantum electromagnetics (QEM) are discussed with a view toward illustrating basic concepts and making some connections with classical EM. The similarities and differences between the mathematical representations as well as the physical interpretations in the quantum and classical cases are reviewed, and a brief discussion of the different objectives and quantities to be measured/computed in quantum and classical regimes is provided. The role of the classical Green function in rigorous, fully quantum electrodynamics (QED) is highlighted, and an example of quantum state evolution in a graphene environment is presented.

中文翻译：

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量子电动力学与经典案例的比较：量子与经典电磁学的异同

在本文中，讨论了量子电磁学 (QEM) 的各个方面，以阐明基本概念并与经典 EM 建立一些联系。回顾了量子和经典案例中数学表示以及物理解释之间的异同，并简要讨论了量子和经典体系中要测量/计算的不同目标和数量。强调了经典格林函数在严格的全量子电动力学 (QED) 中的作用，并展示了石墨烯环境中量子态演化的一个例子。