Quotes from Alan H. Guth

Despite its name, the big bang theory is not really a theory of a bang at all. It is really only a theory of the aftermath of a bang.

It's hard to build models of inflation that don't lead to a multiverse. It's not impossible, so I think there's still certainly research that needs to be done. But most models of inflation do lead to a multiverse, and evidence for inflation will be pushing us in the direction of taking [the idea of a] multiverse seriously.