[music] I'm Alexander Heffner, your host on The Open Mind.

I'm delighted to welcome our guest today, Dan Levitt.

He's an accomplished science writer, documentarian, and author of the book What's Gotten Into You The Story of Your Body's Atoms from the Big Bang to Last Night's Dinner.

Welcome, Dan.

A pleasure to finally record with you.

Thank you.

I'm really happy to be here.

So I know you tell a story from the outset of the book about an interaction, with your daughter, that was kind of the inspiration and framing of the book and the eventual title and subtitle of it.

Tell our viewers about that, that interaction and kind of how you got to that place of thinking about, you know, every movement in our body, derive from, that Big Bang movement, so many, so many years ago.

Well, the inspiration really was when my daughter was a teenager.

And she decided she wanted to become a vegetarian.

And like any concerned parent, I wondered what she would have to eat in her diet in order to be healthy.

And I realized that I, number one, I didn't really know.

And number two, I didn't really know what our bodies were actually made of.

I mean, I know we're made of cells and bone and skin, right?

But, what are they really made of?

And so I just began thinking and googling and researching and it didn't take me long to realize that, you know, I didn't even know where the stuff that we're made of came from.

And ultimately, it led me back to realize that every single particle in our body came from the Big Bang, 13.8 billion years ago.

And to me, that was just a fantastic story because, you know, it raised all kinds of questions about how you go from a collection of particles to us here on a solid planet, living and breathing and speaking.

-And so that was... -So since.

Yeah.

Since we were not present those billion years ago, Dan.

How do we know that?

You know that's the critical question that a scientific mind would ask.

You know, how are we able to know that?

Because we weren't present all that time ago.

And that's one of the most amazing things about science is that we can look back not just 100 or 1000 years, but millions and billions of years.

And so the book actually traces how scientists learned about the different stages in the evolution of matter and in the evolution of the universe and the origin of the universe really started with Einstein's equations of relativity, which is, you know, it's bizarre and it's shocking, right?

But Einstein created these, equations of general relativity that describe the relation between time and space.

But, the person who came to, really first highlight the fact that the universe had an actual beginning, right?

13.8 billion years ago was a Catholic priest named Georges Lemaître, who, to Einstein's dismay, demonstrated that Einstein's theory actually showed that the universe had an actual beginning, a moment in time.

What did it say to you, first of all, that it was someone from a biblical tradition, a priest, who was asserting that, you know, when in fact, the timeline, according to the Old Testament is a little bit different?

Well, that's actually a really fascinating story, because Lemaître was very religious.

But he was also, from a young age, fascinated by science.

And he studied physics in university as a young graduate student.

He actually tried to prove, that the universe began with light, as the Bible said, right?

With photons is what he wanted to do, right?

He soon discovered that that was not going to work.

But, when he dug.

But, in the 1920s, he heard of some hazy astronomical observations that the stars that were further away from us were expanding and moving faster than the stars closer to us.

And from that he deduced that the universe was expanding.

Now, Einstein hated the idea for, you know, for a number of reasons.

One was, it seems ridiculous, right?

I mean, how could the universe expand?

I mean, we're here.

It just doesn't seem like that would be possible.

And he told Lemaître that, this is ridiculous, no way is this true.

Because Lemaître actually tracked him down after his theory was ignored.

But Lemaître dug into Einstein's equations and reasoned that the universe is expanding now.

Earlier, it was smaller, earlier was smaller, earlier was smaller.

And so the logic suggests that at some point in the distant past, the entire universe was contained in a tiny, infinitesimal point of space and time.

Again, Einstein hated the idea.

I mean, I mean if the universe started at a particular point and there was no time before then, what was before then?

Or if the universe is expanding into space, what is it expanding into?

If there was no space before before the Big Bang?

And so Einstein actually really thought that the theory smacked of religiosity.

He thought that Lemaître was inspired by, his religious beliefs.

But Lemaître had really passed that point where he wanted to find any direct connection.

And so he was, you know, he really believed that the Big Bang, which is what Einstein eventually came around to accepting because there was much more astronomical evidence, which in fact showed that, the data was there and Einstein's equations actually do show that the universe began with the Big Bang.

Lemaître was convinced that the Big Bang provided a veil, beyond which we can't see.

And so he turned to science to understand how the universe evolved and was created, evolved, but for salvation, he still looked to God.

He was very, very religious and remained a very active member of of his religious order, for his entire life.

But it sounds like he was able to reconcile or relate the two things in a way that he found intellectually pure.

Absolutely.

Absolutely.

He found no conflict between the two.

That's right.

And that's a lesson, I think, for today in this generation, because we've been observing.

It's not pedaling.

You and I haven't been pedaling, but we are in the midst of people pedaling.

A lot of divisive rhetoric on, you know, one versus the other when, there are, in fact, a lot of people throughout history who inhabited both, scientific and theological, ideas, that they, rationalized, and, that they found to be part of their human experience.

Yeah, absolutely.

And actually, there were quite a number of other figures in it that I, wrote about in the book who were also quite religious.

Can you give us a few more examples?

I'd love to hear.

Yeah, well Victor Hess, who was a, I believe he was a Swiss, physicist who he went up in the balloon and discovered that, the Earth is showered by radioactive particles.

He was extremely religious.

So was the, Nobel Prize winner, Charles Townes, who invented the laser.

And also, you know, I wrote quite extensively about him in the book because he was the first one to help us understand that there are organic molecules existing in space, which, you know, for many, scientists today, that suggest that there could be life elsewhere in the universe, or maybe those organic molecules actually drifted down to Earth and helped create life here.

Townes was completely convinced that this was feasible.

But at the same time, he was very, very, deeply religious and didn't see any conflict between the two.

Well, you know, there is something [sigh] that is kind of holy about the Big Bang.

I mean, there's something that, you know, again, the timeline doesn't align necessarily with religious texts, but, the whole spiritual notion of the Big Bang, there is something, that seems spiritual or religious about it's origin.

When did people start thinking about this through that frame of, you know, a Big Bang, like the earliest articulation of that science?

When was that?

That was the work that Georges Lemaître did.

Yeah.

So, it was 1927, that he began his investigations and went back and forth with Einstein for a number of years.

But, so it was really in the 1920s because before that, people assumed, scientists assumed what, you know, one would think, which is that the universe always existed, right?

How could it not exist?

So it really wasn't until the very late 1920s that people even began to consider it.

And the Big Bang theory was, although Einstein looked at the evidence very carefully, and after a lot of protestations, he ultimately accepted it.

But there was a tremendous amount of resistance that went on for quite a while, particularly from a brilliant physicist named Fred Hoyle, who pioneered, the alternate theory, which was called the Steady State theory, that the universe always existed, and that, somehow he had to come up with other explanations for some of the experimental data that scientists had found.

And it really actually was not until the early 1960s, with the discovery of the background radiation that we find throughout the entire universe, that all of a sudden people were finally convinced, oh, this is it.

And it was discovered the paper came out just before Lemaître died, just like a week before he died.

But that's surprising to me, Dan, and I just want to make sure that I was clear in my question to you.

I wasn't.

I didn't mean the expression of the Big Bang or the the exact formulation that we've come to understand now.

I mean, you know, historically speaking, this idea again, the time people have debated the timeline according to maybe their religious orientation, but were there people who did inhabit that point of view that, you know, there was something miraculous that happened that has to have both a scientific and religious explanation.

Like, surely there were people who felt that way before the 1920s and that was just that was my question to you.

More like, where were the the building blocks for the process in the 1920s?

If there were any, that thought of this kind of in the same way that was the, correction of the idea that, the egocentric idea that we are the center of the universe, rather than one of, you know, many planets, revolving around.

I seem to think of it in that same respect, like the idea of, we were always here.

This was always here, being more driven by maybe, I don't want to say selfishness, but like, a human centric perspective.

So I'm just curious about prior to Einstein, you know, was there any talk that resembled the Big Bang or this idea that somehow something really major happened for that spontaneous generation of, particles that we live in today.

There might be.

But I'm not aware of it.

Uh huh.

So, I'm not really sure.

Of course, there were debates about the age of the Earth, Mm hmm.

for a long time, right?

You know, but the question of whether the universe actually had an origin or not, I have not heard of any.

So as this has evolved in kind of contemporary understanding, what's been most interesting or surprising to you in the feedback on your book?

As people have, you know, read it and thought about this same question that Einstein contemplated that we're talking about today.

Anything new, any new insights that you feel you picked up, through the reaction to the history that you recount?

Well, you know, one of the.

In the book, I really tell the story of the journey of our atoms from the Big Bang through the creation of the stars, the creation of the elements that are in our body, the creation of our planet, and then how those elements on our planet gave, created life, and then how those molecules, those particles ultimately from the Big Bang 13.8 billion years ago, now found their way to our body and are within our bodies.

And tracing that story for me has been, it's really been fascinating, but it's also given me a tremendous appreciation for, the nature of the universe that, I live in and the miraculous nature of our existence here that I didn't have before.

And how lucky we are and how, you know, how many small differences, changes in the laws of physics or the way things evolved could have meant that we're not here at all.

And I think a lot of readers, have responded to that.

You know, there is a kind of spirituality that I find in tracing this story and understanding it and the kind of awe that I've gained from it, that I didn't anticipate when I started to tell this story.

That's something that a lot of people have, I have responded to.

[laughs] I got a, email from one scientist, I think it was in the Netherlands who said, I was planning to be buried.

But now that I sort of understand how my molecules came from the air and from the Big Bang, and from someone, I'm going to, you know, have them cast out to sea because I want them to, you know, continue to, be involved in future life.

And when you think of these kinds of, you know, research projects, endeavors, what, you know, what to you, has the most enduring value?

When you think of those atoms and, you know, the sort of question of, how we've evolved in, you know, over the generations, like, there's the temptation to make this abstract, but what do you think is the most sort of fertile ground to really understand this in a way that feels most accessible?

Well, the thing that was one of the biggest surprises to me was not simply that every single particle in our body, you know, whether they were electrons or quarks.

You know, were all together 13.8 billion years ago in a tiny, infinitesimal part of space.

And now a small collection of them have reassembled in my body and yours to create us.

Mm hmm.

But also that, there's been an evolution of matter from the Big Bang through the creation of stars.

And the creation of stars meant that we went from just having a handful of elements from the Big Bang to, with stars and with the explosions of stars.

We have the, you know, 100 and some 120 some elements that exist in the universe and 25 or so are the ones that are in our bodies.

Those are the ones that create us.

But, then when you get to Earth, what happens is, once you have life, life completely terraformed Earth, completely transformed Earth.

Earth, when it was initially created, had noxious gases.

If you'd gone back there, you know, 4.3 million years ago, you would have choked, you would have died.

You couldn't possibly exist.

There was no oxygen, it was the development of photosynthesizing bacteria, which turn out to be our ancestors, which unleashed oxygen in the atmosphere, which is extremely caustic, but made possible the creation of new kinds of life and new ways of generating energy.

And ultimately, that warmed up the planet and created a balance, between the insulating carbon dioxide in our atmosphere and the oxygen which allows us to breathe and to get energy.

And it was that balance that made our Earth habitable.

Unlike another planet that got so hot, that although there was initially water, life could no longer possibly evolve or exist.

So if it hadn't been for the development of photosynthesis, our planet would have been much, much hotter than it is now.

And, photosynthesis it didn't just give us the oxygen.

It also created a balance of carbon dioxide and oxygen, which kept the temperature of the planet stable.

And so, one of the things that I think about a lot these days is a lot of people talk about terraforming Mars and going to Mars.

Earth is habitable because, over millions and millions, hundreds of millions of years, the balance between carbon dioxide and oxygen made Earth the place where we could live.

Mars has none of that, you know, and the idea that we could easily terraform Mars and make it hospitable, I think is a bit misguided and so what that leads me and this is, I guess, the punchline, right?

Is that it leads me to think that there really is no planet B, right?

We're stuck with Earth.

This is really the only realistic place where we can exist.

And so we really need to think about that and really take, take care of our planet, because there is no other feasible place for us to go.

I think that's a really remarkable point.

The idea almost, that photosynthesis was as instrumental as the Big Bang.

You know, without photosynthesis, the Big Bang, doesn't matter.

But is your point also that the Big Bang happened in a way that, allowed for photosynthesis?

Because now I'm thinking about photosynthesis as this miracle event.

It is a miracle event.

The Big Bang released, certain elementary particles.

And those clouds of those created the stars and within the stars, other larger, and heavier elements were formed and, clouds of those created the planets.

And then once the Earth was created and life evolved, photosynthesis evolved.

So the Big Bang did not create photosynthesis, but the laws of physics.

That allowed those particles from the Big Bang to be released created the possibility of photosynthesis.

Now, what's interesting is that there certainly was life here on Earth without photosynthesis, right?

So, photosynthesis is not necessary for life, but it is necessary for us, for animals, for animals that, unlike bacteria, need a lot of energy in order to be active and move around and to grow to any size.

And, it was through the development of mitochondria and photosynthesis, that mitochondria allowed organisms to use energy more efficiently.

That animals and larger organisms were able to evolve.

And there are scientists who speculate that if there was no photosynthesis on other planets and therefore no oxygen in their atmosphere, you might also find bacteria there, but you won't find any intelligent life.

I just wanted to spend a few minutes.

before we end on the state of research that allows, findings like, Einsteins and the histories that are constantly evolving in this research.

What in your mind is the most compelling argument?

When we think of, all that is still unknowable that we want to explore, when you are dealing with a chorus of people saying, well, we know enough, what's the best way of, addressing that?

Well, first of all, I think most of us agree that we don't know enough because we all want to have new medical breakthroughs that allow us to live longer.

You know, I think we desperately need, ways of creating energy that are cleaner than the ones that we have now.

You know, we still have world hunger.

You know, there are pressing problems in the world that science can address.

But, you know, one of the things that I saw in the book when I researched the book, was that, scientists were often when a new theory came along, very skeptical.

And, you know, many of them fell into cognitive biases, you know, kind of thinking traps about, no that's too weird to be true, or that's just so unlikely because it's not the way I've thought about things before.

And often that meant that communities of scientists for, a fair amount of time really, were not willing to consider theories that we now recognize, like the Big Bang as incredible breakthroughs.

But really, the superpower of science is that collectively, scientists really value, above all else, really honoring the evidence and examining the evidence and being willing when new evidence comes around to reexamining their theory and reconsidering their positions.

And that really is, you know, the only way that science has been able to progress and give us the material progress that we have today.

And, you know, I think that's something that we all need to.

Yeah, we all need to think about.

Yeah, I think that's a very good answer.

But I would stand by my framing that at least we're living in a culture now.

That is putting a stamp on this idea that it's, there are more important things, and I regret that.

And it may just be my view, but I think what's transpiring now with the politicization of, you know, scientific endeavor, is to say efficiencies and cost cutting, are more important than what you just described, which is the constant churning of knowledge.

Let me be wrong and you be more, you know, optimistic.

At least you state a position that I find optimistic, on this question of what's the persuasive argument for, you know, continued investment in knowledge and learning?

I thought your answer was compelling, and that's what I asked you for.

Yeah, I mean, I don't disagree with you.

I mean, I think that, the changes in the, policy changes that the administration is proposing now are going to set back American science tremendously.

I think they're really going to ruin careers, not ruin careers, but, well, they may ruin some careers.

But, they're really going to make it much more difficult for, science to be conducted.

And I'm not suggesting that we should be optimistic about that at all.

I just, you know, I wish that, there was, a more widespread in our society, commitment to, at the end, really respecting the evidence and being humble about what it is that we know and being willing to reexamine what we know again and again when new things are discovered and new ways of, thinking about things are proposed to us.

Dan Levitt, author of What's Gotten Into You.

Thank you so much for your insight today.

Thank you so much.

This has been great.

Appreciate it.

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