In this model, the universe is a kind of cosmic Russian Doll, with all previous universes contained within the current one.
That’s an extraordinary discovery: evidence of something that occurred before the (conventional) Big Bang.
Today, another group says they’ve found something else in the echo of the Big Bang. These guys start with a different model of the universe called eternal inflation. In this way of thinking, the universe we see is merely a bubble in a much larger cosmos. This cosmos is filled with other bubbles, all of which are other universes where the laws of physics may be dramatically different to ours.