The questions I fear are: how did the universe come into being and what is spacetime?

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THERE ARE two questions that I’m somewhat apprehensive about when talking about science to the public. And, unfortunately, they are quite common, because they are of interest to everyone, including me.

First: “What was there before the beginning of the universe?” Second: “What is space-time?” You might think that I would really welcome the opportunity to answer questions like these, because they get to the heart of what theoretical cosmologists like me do. This is literally stated in the job description that I often tell people about: to try to understand the origin and evolution of space-time and everything that is inside it. …