Quantum and classical physical states are represented in a unified way when they aredescribed by symplectic tomography. Therefore this representation allows us to study directly the necessary conditions for a classical universe to emerge from a quantum state. In a previous work on the de Sitter universe this was done by comparing the classical limit of the quantum tomograms with those resulting from the classical cosmological equations.In this paper, we first review these results and extend them to all the de Sitter models. We show further that these tomograms can be obtained directly from transposing the Wheeler–De Witt equation to the tomographic variables. Subsequently, because the classic limits of the quantum tomograms are identified with their asymptotic expressions, we find the necessary conditions to extend the previous results by taking the tomograms of the WKB solutions of the Wheeler–DeWitt equation with an any potential. Furthermore, in the previous works, we found that the de Sitter models undergo the quantum-to-classical transition when the cosmological constant decays to its present value, we discuss at the end how far we can extend this result to more general models.In the conclusions, after discussing any improvements and developments of the results of this work, we sketch a phenomenological approach from which to extract information about the initial states of the universe.

中文翻译：

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层析描述中从初始量子态涌现的经典宇宙

量子和经典物理状态在用辛断层扫描描述时以统一的方式表示。因此，这种表示使我们能够直接研究经典宇宙从量子态出现的必要条件。在之前关于德西特宇宙的工作中，这是通过将量子断层图的经典极限与经典宇宙学方程得出的极限进行比较来完成的。在本文中，我们首先回顾了这些结果并将它们扩展到所有德西特模型。我们进一步表明，这些断层图可以直接通过将 Wheeler-De Witt 方程转换为断层变量来获得。随后，因为量子断层图的经典极限是用它们的渐近表达式来识别的，我们通过获取具有任意势的 Wheeler-DeWitt 方程的 WKB 解的断层图，找到了扩展先前结果的必要条件。此外，在之前的工作中，我们发现德西特模型在宇宙学常数衰减到其现值时经历了量子到经典的转变，我们最后讨论了我们可以将这个结果扩展到更一般的模型的程度。结论，在讨论了这项工作的结果的任何改进和发展之后，我们勾勒出一种现象学方法，从中提取有关宇宙初始状态的信息。