霍金谈到20世纪20年代的德国，当时已经开发了量子力学的基础；然后又谈到20世纪60年代的英国剑桥，当时现代宇宙学的框架已经建立。

Hawking spoke of Germany in the 1920s, when the foundations of quantum mechanics were developed, and again of Cambridge, UK, in the 1960s, when the framework of modern cosmology was established.

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