This is an IHeart podcast.

Everybody wants to know where we came from, how we got to be here.

That means understanding the events that set in motion your life, all of its ups and downs.

Historians can tell you about the journey of your ancestors, how it shapes your culture and way of life.

Anthropologists can tell us the story of humanity itself, why we walk on two feet and how we got to be so darn smart.

But physicists can take us deepest into the past.

Even beyond the chaotic formation story of our solar system or of the galaxy itself,

incredibly, we can look billions of years deeper into history to a time before there were galaxies

or stars when the universe was filled with a hot,

dense plasma. But then we hit a wall. Beyond 13.8 billion years ago, the universe was opaque

and all photons emitted before then have been lost, reabsorbed. And beyond another 380,000 years, the universe was so hot and dense that our theories of

physics no longer apply, like trying to explain steam using fluid dynamics.

Our curiosity, of course, is limitless, and so we desperately want to know what came

before, what is the original fundamental context of the universe? And what does it say about those of us scratching out a living on a tiny dot of rock? Today we'll take a tour of the current ideas about the earliest moments in the universe, if there even were any, and think about what we might

learn in the future. Welcome to Daniel and Kelly's extraordinary ancient universe.

Hello, I'm Kelly Wienersmith. I study parasites and space. And today we're talking about where it all began. Hi, I'm Daniel. I'm a particle physicist, and I love physics because it subsumes every other question in science.

So today we're talking about what happened before the Big Bang. Do you think will we ever get solid answers where we're like, bam, we don't have to debate this anymore, we've got to figure it out, or is this the kind of thing that we will always be tinkering with? I think either answer is okay and exciting, I should say. Yeah, I don't think there's going to be a moment

where we're like, yeah, we figured it out, and here's the rest of the grant money back, by the way. We have nothing else we're curious about and we don't want to think about it anymore. No, I think we're always going to wonder, what about this, what about that, where did that come from? Why not this? Why are the other thing? I think it raises a lot of philosophical questions just thinking about the origins of the universe, but also wondering which answers are acceptable, which ones we go, yeah, that makes sense. Let's move on. And which ones were like, wait a second, why that? I think that reveals a lot about our humanity and our curiosity, which is one of the reasons why I love this topic so much. Yeah, and we've talked on past shows about why there are some explanations we get where we're like, oh, that makes sense. We don't have to dig any deeper and how that can like sort of send us down the wrong path, actually, by just, you know, oh, that makes sense. No more questions needed. Yeah, exactly. And whether aliens would find those answers satisfactory or not.

Mm-hmm.

I know, the constant question that is ringing in Daniel's mind.

What would the aliens say?

Exactly.

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