The problem of objectivity, i.e. how to explain on quantum grounds the objective character of the macroscopic world, is one of the aspects of the celebrated quantum-to-classical transition. Initiated by W. H. Zurek and collaborators, this problem gained some attention recently with several approaches being developed. The aim of this work is to compare three of them: quantum Darwinism, Spectrum Broadcast Structures, and strong quantum Darwinism. The paper is concentrated on foundations, providing a synthetic analysis of how the three approaches realize the idea of objectivity and how they are related to each other. As a byproduct of this analysis, a proof of a generalized Spectrum Broadcast Structure theorem is presented. Recent quantum Darwinism experiments are also briefly discussed.

中文翻译：

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客观之路：量子达尔文主义、频谱广播结构和强量子达尔文主义——综述

客观性问题，即如何在量子基础上解释宏观世界的客观特征，是著名的量子到经典过渡的方面之一。由 WH Zurek 和合作者发起，这个问题最近得到了一些关注，并开发了几种方法。这项工作的目的是比较其中三个：量子达尔文主义、频谱广播结构和强量子达尔文主义。论文集中在基础上，综合分析了三种方法如何实现客观性思想以及它们如何相互关联。作为该分析的副产品，给出了广义频谱广播结构定理的证明。还简要讨论了最近的量子达尔文主义实验。