- [Anne] Michelle Fowler can't remember a time when she was not obsessed with space. Her mom says that as soon as she could talk, she began pointing at the stars. So no surprise that she became an astrophysicist. Then she met and married another astrophysicist, Andrew Booth, and they became a space research power couple. For 26 years at NASA's Jet Propulsion Lab and Goddard Space Flight Center. And then in 2019, out of the blue, Andrew was diagnosed with a rare form of brain cancer, and he died less than a year later. Michelle has given very few interviews since then, but there was one I've never forgotten. Her grief at the time was an enormous black hole. But she talked about finding solace in the structure of the universe, in the very nature of space time itself. Michelle, I have wanted to talk with you for two or three years now, at least since I heard the Science Friday interview you did. And it was so beautiful. And I kind of, at the time, the reason I never called you is I kind of felt like I, it's a really intimate moving story that you had to tell. And I thought she's told it, like, don't try to get her to tell it all over again. It's, she put it out there in public, but then we're doing the show on infinity, and I just thought, oh, maybe she'd be up for talking. So anyway, I hope this is all okay with you.
- [Michelle] Well, I'm so glad you did. No, it's wonderful to be with you too. I think that when you're widowed, people think that they sort of hate to bring up the whole, your spouse died situation because they think it will upset you that it'll bring something back, trigger something. But the thing is that it just becomes part of the air that you breathe. You never forget it. You're never away from it. It just becomes something you just, like I said, you just live in. And so I think that people should be less afraid of talking about this to people who've lost spouses or children or any type of deep grief.
- [Anne] And how strange to live in a culture that is afraid of grief and the one thing that if anybody is experiencing grief, it's the one thing we should be talking about. Anyway, there's, I think this is kind of an archetypal experience that a lot of us have. It's summertime, it's night. You're lying on the grass, you're looking up, hopefully it's someplace really, really dark. And it's like layer upon layer of stars as far as you can see. And you know that feeling, that's almost like a head rush a little bit. It's, you feel dizzy in the face of that immensity. And I was thinking, well, I wonder if that's because that's a little tiny brief perception of infinity, which otherwise I think is almost impossible to wrap our heads around.
- [Michelle] Yeah. And infinity is a slippery thing for me because it seems as you look out into space that that goes on forever. And you said something very important, very cognizant there just a minute ago, you talked about layers upon layers of stars. And in fact, the reason that you don't see a bright night sky is one of the proofs that the universe cannot be infinite in both space or time.
- [Anne] Okay so first of all, I feel so stupid because I've been using the infinite and the universe as synonyms. The universe is not infinite?
- [Michelle] Well, the disheartening and also lovely and encouraging answer to that is we don't know yet. We know we are absolutely certain we have not seen to the edge of the universe yet. Would you like me to break this down for you a little bit?
- [Anne] Yes.
- [Michelle] Okay. So our view, our observable universe, the universe we can observe right now has a very specific boundary. And that's because as you look farther and farther out into space, light takes more and more time to travel to you. It's in effect, a lot of people understand the sun takes eight minutes for light to travel the 93 million miles away that the sun is. The nearest galaxy in the sky is 2 million light years away, Andromeda, the nearest big galaxy. So with binoculars tonight, if you look up at Andromeda, you see it as it was 2 million years ago. So as you go farther and farther out and look farther and farther back in time, we see the universe get hotter and denser. And we see it change. We see the chemistry change. We see the objects change until finally you get to a barrier. If you look any direction in a giant sphere around the earth, pick any direction and look so far away that you're looking about 13.7 billion years ago. And at that time, the universe was so hot, it was as hot and bright as the surface of the sun. And we can't see any further than that.
- [Anne] We can't go past that.
- [Michelle] Telescopes can't see past that. So we know for a fact that we cannot see the entire universe. So we don't know whether it's infinite or whether there is some larger shape to the universe, shaped to space and time. Could there be other universes out there?
- [Anne] One of the things that's so fascinating, listening to you talk, it really becomes clear what Einstein said that space and time are the same thing. They're wedded to each other. You have written and talked incredibly movingly about how this perspective on the universe, your perspective as an astronomer, as a space scientist, helped you survive excruciating grief after the death of your husband. You and he talked in terms like this, I think right as he was during that last year as he was dying.
- [Michelle] Absolutely. He and I, we did the whole thing with our eyes open and holding hands and with the humility of not knowing even what time means, because this is nothing new. I mean, you mentioned Albert Einstein and he and a number of physicists more than 100 years ago, really did take it seriously that space and time are the same thing. And they don't seem to our brains. I mean, time seems to progress in one direction. While space, you can move in many directions, space may be infinite, whatever. They really thought that if you had the right perspective, and it would probably be not in our own three dimensions or four dimensions with time that you would see all of time as a complete whole thing. And so Andrew and I sort of took a deep breath and said, well, we're not really leaving each other. I'm going to have to go on now alone, but all time exists at once. And here I am holding your hand. And when the universe began, the first instant of time happened, I was here holding your hand. And when the universe ends, whatever that means, if it does, I'll still be holding your hand. I'll still be right here with you. Einstein wrote a letter to his best friend's wife after his friend had died and said, this person is still with us every bit as much as they were, every bit as alive. We are in a landscape of time, and they're kind of over the hill from us now. But now here we are over another hill where they're not. You just kind of let yourself dissolve into, again, like I said, the humility of really not even understanding what reality is. We kept that with us as we made that journey.
- [Anne] What was Andrew like? The two of you shared a profession. He was an astronomer too.
- [Michelle] Oh, he was my, he was, ah he was who I wanted to be in many ways. I really admired him to the depths of my soul. I mean, he was absolutely brilliant. He was a kind of a quantum optics person. He did interferometry, a technique of building a telescope that only works if reality is stranger than we know. An interferometer, yeah. I mean, this is how they made pictures of the giant black hole with the event horizon telescope, where they link telescopes all around the world to actually act as one single telescope. And in order to get these things to work, the same particle of light has to appear from that star or disc around the black hole. That same particle of light has to appear at all eight telescopes at once.
- [Anne] That's just so phenomenal that you actually have to zoom in on the same particle of light.
- [Michelle] If you can set your telescopes so accurately that they're actually down to the quantum mechanics level of accuracy, you can catch a particle of light at eight different places at once. And only then will the telescope work. So already we have proof that our idea of what space and time are is a simplification. Our brain is seeing a slice of something, but not the whole thing.
- [Anne] So you are already used to thinking in terms of impossibility. I mean, things that seem impossible to the rest of us seemed real visceral to the two of you.
- [Michelle] So, Andrew was a wizard and he was always playing "Dungeons and Dragons" games. We loved dressing up as wizards. He was joyful and humble and friendly. And when he died, there's this brilliant man at NASA, I mean, it was all of the administrative assistants and the security guards and the people that said he tried to include us. He was so kind to us. And yeah so I mean, he gifted me with that. I mean, I, trying to figure out my identity after losing that 'cause we were each other's best friends. We didn't have a whole lot of other friends than each other. And that was a hard, hard journey. But I promised him that I would do it and he actually made me write it down. He wrote in Elvish a goodbye letter. And, he spoke Elvish. We were that type of nerds. And so he.
- [Anne] I was too. I kept up and my daughter kept a journal in Elvish and I.
- [Michelle] Yes.
- [Anne] I used to write in, yes, yes.
- [Michelle] So, I've got a tattoo that goes all around my body and it's him saying.
- [Anne] It's a hug.
- [Anne] Get out there, love, live. You know, off you go.
- [Anne] Wow. You had some time. I mean, he died of brain cancer.
- [Michelle] Exactly, we had that time.
- [Anne] So you did have some time to think about how he wanted to die, how you wanted to be together and to think about what it would be like for you afterwards. I'm sure it helped some, but.
- [Michelle] Yeah, oh, it did.
- [Anne] Your life still breaks.
- [Michelle] It does, it breaks entirely. And then you start a new one and there, I mean, there's nothing the same after the death of a spouse like that. I mean, it just, I mean, you have to mourn not only your husband Andrew, but you have to mourn the version of yourself. I mean, the version of myself that existed before his death is largely gone. It's changed. I've had to find new ways to breathe, new ways to walk and we all go on journeys like that. And so the empathy for each other that, like you said, a society that doesn't even wanna talk about grief, we're all left to reinvent the wheel. And just having somebody say, I'm with you on that journey too. Most of us, if we live a full, wonderful human life, we'll deal with deep grief,
- [Anne] And to a certain extent, I mean, we do all experience the kind of tragedy of living in time. You know, my two children are grown and off on their own and living their lives, and I'm really happy for that. But I feel grief that if I see a photo of the two of them building a sandcastle on a beach at age two and four, they are not those two and four year olds anymore. They are not anymore the children that I adored when they were little, those two children are gone and they don't even have continuous memories of who they were. And so, in this lesser way, we all know that experience that you're talking about of having carrying multiple universes in our heads and in ourselves. We are, none of us who we were, and the people that we love are not who they were in the past.
- [Michelle] I love the idea in Buddhism that the universe may just pop in and out of existence, with all of our memories intact and all this light traveling billions of years. There's actually some relevance for that, even in science, like you said, there are many lives we've lived, many universes we've lived in, and there may be actual physical branchings of this moment can lead to many universes, perhaps an infinite number of universes. But it also goes into the past that maybe different universes led to this moment. And so.
- [Anne] Do you mean that literally not just, I mean.
- [Michelle] Yeah.
- [Anne] It kind of sounds like science fiction, but I mean, do you really mean literally?
- [Michelle] You know, the idea that there could be many universes branching in all directions, it's sort of like just seeing things from a different perspective. You know, if time exists all at once, maybe if you can see in another dimension above that, you see different versions of time, both of the past and of the present. There's a cool thing which I'm not gonna claim is proof of this, but I think it's interesting. And one is the idea that there may not just be multiple futures. There's a future where I decide to go outside today, there's a future where I don't, and all of a sudden they both really exist. That this is an interpretation of quantum mechanics. One of the ways that a particle of light can be in eight telescopes at once is that those are all real, but separate universes. But the telescope can kind of dovetail them together because the telescope is set so accurately.
- [Anne] Okay whoa. That's just mind blowing. When you said it's the eight telescopes zooming in on the one particle, I thought, okay, it's one particle in a particular moment of space time and all those telescopes are trained on this one particle. You mean the particle exists simultaneously in different?
- [Michelle] Yes.
- [Anne] Oh.
- [Michelle] Some people think it's something called quantum entanglement. And quantum entanglement is sort of, if you take two atoms and let them interact with each other and then separate them, somehow they'll kind of remember each other. We do this experimentally all the time in laboratories all over the earth. China did it up to their space station and back. You take two particles that were once close together, you move them apart. And all of a sudden now the universe says these two things are basically the same, even if they're separated by what we think of as a lot of space and time, a billion light years, they adjust simultaneously because the universe doesn't really care about what we think of as space and time. Space and time is not an intrinsic property of the universe. It's some way that our mind kind of breaks things down. And so now we wonder if space time itself, what is it made of? Maybe it's made of these entanglements, maybe we are entangled to everything. Maybe we're entangled to particles that are so far away from us now they're outside that limit of that background that's so hot and bright. Maybe we're entangled to everything in the universe.
- [Anne] I mean, and Michelle, we were talking about you and Andrew. I mean, of course I'm thinking, and maybe you and Andrew are still entangled together.
- [Michelle] Oh, absolutely.
- [Anne] Still.
- [Michelle] There's no way we couldn't be, spending so much time in proximity, sharing, I mean, every square foot of air has as a one with 27 zeros after its molecules, sharing molecules, you're entangled to everything. Not just in space, but also in time. Like I said, it doesn't so much help the human psychological aspect of grief, but it's a way of letting go and saying that we don't even understand what reality is yet. And we may just be looking at this wonderful huge shape that's the universe, our brain cuts it into slices. But I'm still every bit as much with him now. I don't expect to find another version of him in an afterlife. I don't know whether that's true or not, that's not our belief, but the belief that we had this time together and that that space time always exists. I mean, it's there. I mean, in that way, are we actually eternal?
- [Anne] Michelle Fowler is an astrophysicist. She spent nearly 30 years at NASA as a science communications director, science writer, producer and podcast host.
