Paul J. Steinhardt does not look like a firebrand. With his wiry spectacles and buttoned-up bearing, he would not seem out of place in an office of accountants. But the Director of the Princeton Center for Theoretical Science is an academic agitator, vocally criticizing the leading theory of the universe’s infancy, a theory that he himself helped create more than 30 years ago. According to this picture, called inflation, space itself expanded faster than the speed of light just after the universe’s birth in the big bang, doubling in size 100,000 times in less than a billionth of a billionth of a billionth of a second.
But once started, inflation is hard to stop entirely, so pockets of space should constantly be budding off into new universes with different properties. In such a multiverse, anything that can happen will happen somewhere, and that is a fatal flaw for Steinhardt—a theory that cannot rule anything out is not scientific, he argues. He has been pursuing an alternative scenario where our universe cycles between periods of expansion and contraction, so that the big bang was really a big bounce. Most other researchers are skeptical of the approach, but Steinhardt is undeterred.
And his search for alternative schemes is not limited to cosmology. For decades, he has been pondering the different ways atoms might be arranged in crystals, discovering that arrangements previously thought to be impossible were actually allowed. In recent years he even struck out into the wilderness of the Russian Far East to look for the rarest arrangements in nature, an expedition that yielded minerals new to science, including one dubbed “steinhardtite.”
Both Steinhardt’s passion for unsolved puzzles and his critiques of overly accommodating scientific theories are on display in our video interview.
What does the term “Big Bang” mean?
According to the theory of inflation, what was the early expansion of the universe like?
What caused the expansion of the universe?
You have become a critic of inflation. Why?
Why is it so unsettling to believe we might live in an accidental universe?
What do you think of recent findings supporting the existence of gravitational waves?
You have been working on alternative theories to inflation. What are they?
What is a cyclic universe?
What is the main criticism of the cyclic universe picture?
Can we ever know the full history of the universe?
What does the Higgs boson have to do with cosmology?
How did you get into science?
Can you share some stories about the Nobelist Richard Feynman?
What are quasicrystals?
A quasicrystal is named after you. How did that happen?
How did an inflation researcher like you come to study quasicrystals?
What would you be if you weren’t a scientist?
Interview Transcript
What does the term “Big Bang” mean?
Physicists mean two things when they talk about the Big Bang. What cosmologists usually mean is the idea that the universe was once hot and dense, and has been expanding and cooling. So when people who are non-scientists ask us do we believe in the Big Bang theory, that’s usually what we’re talking about. Is there evidence that the universe was once hot and dense and has been expanding and cooling? And the answer is: There’s overwhelming evidence for that. When the public generally asks us about the Big Bang theory though, they have a different idea in mind. They have the idea of this big bang itself, the big bang beginning, the idea that the universe, you know, at one time didn’t exist and suddenly sprang from nothingness into something-ness and that’s the Big Bang. And if you ask physicists are they confident in that idea, the answer is no. There are different ideas about what might have happened as we go back to that moment in time. People have had ideas over, you know, the last century, of what might have occurred during that time and that’s a subject which is central to a lot of the debates we have in cosmology today.
According to the theory of inflation, what was the early expansion of the universe like?
So if the space between you and me, for example, were stretching at this rate at the present time, you’d be either trying to speak to me by sending a sound wave or we could send light signals, [and] the space between us would be stretching so fast that the light would be having to make up, or the sound would be having to make up the new distance. There would be [space] being created so fast, that [sound waves/light signals] would never get to you, or yours to me. We’d lose sight of one another and lose communication with one another. That’s the kind of expansion we’re talking about when we’re talking about inflation.
And just to put some numbers on it, in typical examples, the inflation begins when the universe is about a billionth, billionth, billionth, billionth of a second old, and it doubles in size roughly every billionth, billionth, billionth, billionth of a second—for maybe a hundred thousand doublings, or a million doublings, or maybe a billion doublings. That means it doubles in size or multiplies by eight in volume, you know, every billionth, billionth, billionth, billionth of a second and after a short time, a region which is smaller than a nucleus blows up to a size which is much larger than the space that we observe today when we look around the universe. We only see a finite patch of the universe. It’d be enormously bigger than that and we’d just be a tiny patch; what we would observe would just be a tiny patch of that piece of space that was once smaller than a nucleus, that blew up and inflated at that time.
What caused the expansion of the universe?
We do not know what caused the inflation. There are, you know… Over the last 30 years, there are probably hundreds, maybe thousands of papers with people with different proposals for what is the precise field or the precise form of energy which—they all have to have the property they self-repel, they all have to produce this accelerating effect, but as for their precise identity, there are lots and lots and lots and lots of different ideas, some of which involve quantum fields like the original idea; some of which involve the use of extra dimensions; some of which use the idea from string theory, quantum strings, or quantum brains—membranes; many, many different ideas, and whichever one you choose by the time you… What we observe in the universe today doesn’t help us distinguish very keenly which one of these ideas is correct. We can eliminate some possibilities but there’s so many—there are many different options.
They all have to have the property that somehow the inflation ends. And the property… I mean one thing that’s always, that’s bothered me about the story since the very first example, is the property of getting this inflation and having it end has always involved some degree of tuning or fine-tinkering of the model, you know, fine-tuning. Every model has some sort of what we call parameters or coefficients or features in it that have to be finely adjusted in order to get what you want. If you don’t adjust them right you get something entirely different, which you don’t want, which is inconsistent with what we observe. So we don’t have what I would call a pretty theory, a theory that naturally explains this process and that’s, you know, one of the problems at present time—is to find something, a natural explanation, for what we observe. And as we observe more properties of the universe, that becomes more stringent and a more stringent constraint on our models.
You have become a critic of inflation. Why?
What we discovered is that it’s possible, that actually it’s possible, and then eventually realized it’s almost hard to avoid that inflation once it starts is really eternal—that it can end in some patches, but it will always continue yet in other patches of the universe and where it continues, it blows up in volume so much that it occupies the vast majority of the universe. And although it continues to produce patches where it ends, the patches that are inflating are always outrunning the regions where it ends, and so you end up with patch after patch after patch where inflation has ended being tiny little specks in a universe where it’s continuing.
Now those patches where it’s ended are pretty darn large—they’re large enough to contain us—so maybe you shouldn’t be, you might not be concerned at first. But the problem is, due to the effects of quantum physics these patches are not all the same. The effects of quantum physics, when you include them properly, lead to a situation where some patches are like us, but some patches are not like us; and in fact, every conceivable possible outcome of the universe can occur if you look from patch to patch to patch and there’s no particular reason why ours is more likely than any other. So in a sense we would live in this picture, in an accidental universe. We’re trying to explain the universe in a simple, forcefully deterministic way, and instead in this inflation universe, it looks like it’s an accident that we live in the universe such as we do. It could have many widely different properties.
Why is it so unsettling to believe we might live in an accidental universe?
First of all, the fact that the universe is so simple on large scales. If you observe something which could be complicated, but it turns out to be very simple, it’s screaming at you that there’s some explanation for why it is so. Now the problem with an accidental universe is that it’s not an explanation at all. It’s not even a scientific theory in the form we’re talking about—in the sense that it allows every conceivable possibility. If you allow every conceivable possibility, then there’s no test or combination of tests that can disprove such a concept. You’re allowed to have that idea if you like, but it’s no longer in the realm of science—you’re some kind of metaphysics or philosophy, which is outside the realm of science.
So the problem with inflation is that it began as an idea which seemed to have definite predictions and properties and, and with the discovery of eternal inflation, the multiverse, it moved to this accidental universe picture where it no longer has any particular test or combination of tests that can disprove it. It’s so flexible—and this is just one form of flexibility we’re talking about right now, it has other forms of flexibility—but it’s so flexible just because of this multiverse that there’s nothing… anything you would observe you’d say, “Oh, that could happen in a multiverse. That could happen too,” you know. You could just go on and on. There’d be nothing that would tell you that the theory could possibly be wrong. And such ideas, as I say, lie outside the domain of normal sciences that’s been practiced for the last 400 years. So I think it’s a very… It’s a kind of, I would call it, a failure mode. You know, usually we’re used to theories failing because they make a definite prediction, you go to make the observation, and it disagrees. That’s science as we normally understand it. It makes a prediction, it gets tested, and it fails. This is different. This is a theory which you thought made definite predictions and now you’ve discovered that it has this sort of infinite way out and so that means it’s just no longer, you know, an ordinary scientific idea, which is a different kind of failure mode than what we’re used to.
What do you think of recent findings supporting the existence of gravitational waves?
You can’t be sure what’s causing that signal. Is it really a signal from the deep part of the sky beyond the galaxies, the thing you’re trying to detect? Is it a signal caused by the dust within our galaxy, twisting the light as it scatters from that dust? Is it a signal that’s caused by the atmosphere, which is constantly fluctuating and distorting the light as it comes to my detector? Is it light that bounces off the ground and comes into my detector and is distorted that way, or is it light that is distorted by the lens in my detector? There are many sources you’d have to look in with just a single frequency. So what they were trying to do was extremely difficult and more than could be done I would say, and so there were reasons to be concerned right off the bat and the biggest concern was, had they taken a proper account of the dust in our own galaxy? And that’s the issue that people have been focusing on most up to this point.
Because we know there is, in our own galaxy, dust, which has the property that light which comes, which scatters off of it, becomes polarized—and that is to say when the light comes, gets scattered off of us, it gets scattered off of the dust. Instead of the light coming toward it with the electric fields oscillating in every possible direction, some directions are preferred over others depending upon the particular dust particle that it scatters off of. Now that is what BICEP2 was trying to measure—was the polarization of light, not by the dust but caused in the early universe by gravitational waves. But they can’t distinguish by themselves which caused it. The dust? Or was it the gravitational waves?
Now, various groups have tried to improve on what they did and conclude that most [likely], that dust is a large contributor and perhaps the entire source of the signal they were seeing. And we’re waiting now for results from the Planck Satellite experiment, which should be presenting us with a detailed map of that particular region of the sky that the BICEP2 team measured and then we’ll be able to say more about the likelihood that they saw these gravitational waves. (See the related blog post, “Excitement About Gravity Waves Comes Crashing Down,” which reports on the Planck team’s finding that the polarization signal could be entirely explained by dust, rather than gravitational waves.)
You have been working on alternative theories to inflation. What are they?
What if we didn’t start from the Big Bang? Maybe that’s not the beginning of space and time; and maybe what we think of as a bang, is really a bounce: a transition from a preexisting phase—let’s say of contraction—[and then] a bounce into expansion. Now suddenly there’s a whole new domain of time, before the bounce, before the bang, [with] which you can introduce processes that would naturally smooth and flatten the universe.
So the theories I’ve been working on have that property. They transform the bang to a bounce, and they introduce processes that would just naturally occur when, in a contracting universe automatically they would tend to flatten and smooth the universe. And then you add the quantum physics into it—different regions of space contracting at different times due to these random quantum fluctuations. You can’t keep things completely in sync—quantum physics doesn’t allow it—so the slight non-uniformity in the rate of contraction will translate into fluctuations, variations in temperature and density after the bounce, that would produce the fluctuations you see in the microwave background. But because this process of contraction is very gentle and slow compared to the very rapid inflationary expansion, it doesn’t produce the violent effects that produce the big gravitational waves, that high amplitude gravitational wave that inflation does. Instead it produces gravitational waves which are much, much weaker, far too weak to be observed.
We have this more realistic, contemporary version, which produces a multiverse in which anything can happen and is completely unpredictive. And then we have a theory which says in the bouncing theory, we shouldn’t see the gravitational waves in this particular kind of… in this kind of bouncing theory, you shouldn’t see these gravitational waves. And that’s the spectrum of models which we know at present and there may be other models yet to be found.
What is a cyclic universe?
The bouncing model which I was just describing is one in which I only talked about a single bounce—taking the most recent bang and saying suppose it’s a bounce, and suppose… In that case it allows, opens up the possibility of the smoothing that accounts for the smoothness we see today, [that it] was produced during the period of contraction before that bounce.
Expand the story a bit. Was that the only bounce? Could there have been a sequence of bounces? Could there have been a kind of episodic or cyclic universe? Yes, all those things are natural possibilities. They’re natural possibilities, but I should say that during each period of contraction, and in each preceding… [and] each such bounce, there’s always going to be this smoothing process, this flattening process which has the property that in a sense you’re kind of erasing information, or spreading out information so thinly from what preceded it, [that] there is almost no trace of it in the universe that you can look at today. You have to look for indirect evidence of this process.
So you don’t see direct evidence of earlier cycles, but you could infer they might exist based on the fact that you see the smoothness and the flatness and the absence of gravitational waves and maybe other properties explained by this sort of episodic or cyclic universe. Now once you have that possibility around theoretically you can also ask the question well, how did it begin? Did it have a beginning? Maybe. It could have had a beginning and then kind of settled into a regular pattern, or as far as we can tell theoretically, it may have continued forever into the past and forever into the future. So there is… the way you get around the problem of beginning is that there is no beginning. It was always there doing this, forever in the past and forever in the future.
What is the main criticism of the cyclic universe picture?
The one remaining issue is the bounce itself. What exactly happens with the bounce, what physics describes that bounce and there, there are several working ideas that people have. Some, in some cases, one [side] thinking about bounces in which the universe contracts to a point and then reverses itself and begins to expand right away before reaching zero size—before having to worry about the effects of quantum gravity. And so we both constructed examples like that. And then there are also examples where [another] says no, let’s go ahead and push on and see if we can explore whether quantum gravity would naturally lead to a bounce. Now both those ideas are under development.
And my view is this, this is the key problem. Whether or not we can have this bounce is the key problem of fundamental physics and cosmology. It relates to fundamental physics of quantum gravity, to the problem of cosmology. Could the smoothing have occurred before? Can we avoid the multiverse problem? They relate. You know, all these things are tied up together and I think it’s the key problem that we should be focusing on, you know, as we enter the 21st century. It’s the key problem we should be focusing on because if we can show it’s impossible, then we have to, definitely have to win, win out over the multiverse. Get control of it. If it’s possible, then I just think it’s a much simpler idea than inflation and the multiverse. Just discard that, and I think this bouncing idea is a much simpler way of explaining the universe in which… the simple universe, which we observe.
Can we ever know the full history of the universe?
I’m optimistic about our being able to figure out the history of the universe at this point because what we’ve observed about it on a large scale is this extraordinary simplicity. If it were complicated, if it looked like it came out of some complicated sausage-making machine, then you’d say, well the fact that I can only observe one part of it and I’m only seeing a little piece of the sausage, it makes it pretty hard for me to figure out the machine that produced it. But that’s not what we’re observing. We’re not observing some complicated sausage—we’re observing an extraordinary symbol of uniformed, featureless—very few degrees of freedom here to describe the universe on large scales.
It’s also true that our fundamental physics if you, you know… recent discoveries about the Higgs in fundamental physics have just shown that to be simpler than many theorists thought it should be. So what… at the present time, I’m saying there’s fascinating simplicity observed on large scales. There’s fascinating simplicity observed on small scales. That makes me optimistic that it should be, that we should be looking for a very simple solution with so little, so few degrees of freedom that you would be in, you’d immediately be able to recognize that that’s a very sensible compelling model to explain what we observe.
What does the Higgs boson have to do with cosmology?
If we assume for the moment that the Large Hadron Collider has seen all the particles to be seen up to high, you know, reasonably high energies, there’s a surprising result that emerges from this analysis. And that is that our present universe is in a metastable state. Instead of being at the lowest energy state in the universe, it’s actually at a state of relatively high energy compared to what would be the minimum. It’s separated from that minimum by a large energy barrier, which is why we are in the state we are in and aren’t immediately jumping to a state of low energy. But ultimately if this picture is correct, we can’t be in a stable state. Eventually, some sort of quantum fluctuation or a thermal fluctuation could, is going to kick us out and we’re no longer going to be in the present vacuum state.
So that means in our present vacuum state, instead of being in a universe in which the vacuum, energy in the vacuum is relatively small and positive—which is the way it is today—and instead of being in a universe which is accelerating its expansion, it’s going to jump at some point into a state in which… that the universe is going to be begin to contract.
This kind of idea is interesting because in the kind of cyclic universe as I was describing, this is exactly what has to be the case. If the universe is going to cycle, it can’t remain in the present accelerating universe, it has to eventually end its acceleration and enter a phase of contraction and here’s the Higgs, maybe providing us with that hint that that will be, that that could occur. Then if it turns out that when you contract you bounce, that would lead to the Higgs coming back to the current vacuum, but now in a universe which is hot and expanding again and the process of expanding and cooling and forming galaxies and stars could begin again.
So this work on microphysics which we, in the Large Hadron Collider, which we don’t normally think about as cosmology—it was really just designed to see if we could see if there was a Higgs at all—has turned out to be potentially very interesting for cosmology, much more interesting maybe even then you’d say for particle physics because it may be pointing us to new possibilities for the past and future of our universe that, that we didn’t dream were possible, and that the Higgs is pointing us to.
How did you get into science?
I think ever since I was a toddler I always wanted to be a scientist. My father used to tell me—he was not a scientist, he was a lawyer—for some reason, he used to tell me stories about scientists and discovering things in science and that just sounded to me so exciting to discover something new that no one had ever known before. I just found that extremely thrilling and so I always wanted to be a scientist of some sort. And so you know from the first books I remember you know, all my experiences were… science was always a big part of my life. And so you know, as a kid growing up I had a chemistry lab between a biology laboratory, between a telescope, and doing that kind of thing, doing lots of research that I could. You know getting, kind of getting involved in research as young as I could.
The one area which I had very little exposure to up to that point was physics and it wasn’t until I was an undergraduate at Caltech that I… I mean I took physics in high school but they were pretty prosaic courses but when I first, you know, realized that physics was really interesting was when I was an undergraduate at Caltech and I, the first year forced to take physics, for the first two years and that professor… you know, within weeks I’d met you know, very exciting people including Richard Feynman and I was completely sold: That’s, that was the science I wanted to do. And then I began to explore different areas of physics because I didn’t know much about physics when I started in it and the very last one I came to was cosmology. As I mentioned earlier, it really was as a post-doc, and I happened to walk into a lecture by Alan Guth—really never having taken a course in cosmology—that’s when I was first exposed to it and it has occupied a big part of my research life ever since.
Can you share some stories about the Nobelist Richard Feynman?
I had several interactions with Feynman. I started a course with him called “Physics X.” My roommate and I asked him if he’d be willing to teach a “pseudo-course”—a false course—called “Physics X” in which he would come every week and he would answer any questions that you might throw at him. And that was a real thrill because literally the discussion, you know, ranged all over the map. It wasn’t just about things you know, the obvious things about particle physics you could ask about. He didn’t even particularly like that kind of question. He wanted you to bring in some phenomenon, some mysterious phenomenon and we would be discussing about you know, what might explain that phenomena. And so it’s a, it was a really important influential experience for me.
And then I also did my senior thesis project with him, so that was another set of experiences so it left there a real mark on my thinking, including my thinking about science which has been coming back to me since the BICEP2. A lot of… BICEP2 has brought in a lot of interesting debate about… that you wouldn’t think scientists would have to debate about—about what is the nature of science, this issue of whether it’s important that science be testable or not testable, falsifiable or not falsifiable. These were issues which I think in Feynman’s mind were extremely clear and I think conventional—I would have said conventional—and certainly in my own mind, conventional and very clear, but, you know, I’ve been hearing some very interesting views that, you know, having a theory which is not falsifiable may be okay in science—and I find that very strange and actually I find it rather dangerous—but it sort of brought me back to rethinking some of my experience with Feynman from those days.
What are quasicrystals?
Back in the 1980s, my student and I had been hypothesizing that there could exist forms of matter in which the atoms and molecules could organize themselves into patterns that were impossible for crystals, but they weren’t random either. In fact they would have symmetries which crystals, patterns do—but symmetries which crystals aren’t allowed to have.
So it’s been known for 200 years that atoms could organize themselves like building blocks into certain patterns where the atoms or clusters of atoms regularly repeat. That’s what makes a crystal a crystal. And if I make things out of building blocks that way, it’s been known for nearly 200 years, there are only certain symmetries which are possible. So all the crystals that you observe in nature up until recently, only conform to one of 32 symmetry possibilities established, you know, in the 19th century. Everything we’ve known up to that point lived that way.
But what we showed, my student, Dov Levine and I showed is that if you get away from the idea of just a single repeating unit, if you allow yourself let’s say two repeating units, so two repeating atoms, which repeat at different frequencies, suddenly symmetries which were impossible become possible. So for example, crystals can never organize themselves into any kind of structure which has five-fold symmetry. It’s forbidden for crystals—mathematically, it’s impossible. But the quasi-, the systems we were thinking about which we call quasicrystals could. In fact, they could arrange themselves and to form a solid with the symmetry of a soccer ball—which has you know many pentagons on it, many, many different axes of five-fold symmetry—we could even get that kind of structure. And while we were working on the this idea, there was a group at the National Bureau of Standards led by Dan Shechtman, which was looking at various aluminum alloys and they stumbled across one which produced a pattern of diffraction which had five-fold symmetry, which was inconsistent with the laws of crystallography. They had no explanation for it but they, you know, said, “Here it is! We don’t understand it, but you know, here’s a possibility.” And it turned out the patterns they were getting conformed precisely with the kinds of patterns we had predicted hypothetically. And so that’s how the idea of, that’s how the discovery of quasicrystals was made—the realization that the hypothetical idea and the experimental idea actually related, came through that and in 2011, Dan Shechtman won the Nobel Prize in Chemistry for his discovery of the… we now call the first quasicrystal.
A quasicrystal is named after you. How did that happen?
All the quasicrystals that have been discovered since 1984, up until recently, were discovered in the laboratory synthetically—and people even argued that they required that; they were such delicate forms of matter that they could only form that way whereas, my own thinking based on, you know, theoretical reasoning was there was no reason why that had to be so. Some quasicrystals might be energetically stable and if so, maybe they’d be found in nature. So I launched a search, a worldwide search to look for natural quasicrystals around 1998 and there’s a long story that goes with it, but about 10 years later we actually found a sample in a museum in Florence thanks to a mineralogist there, Luca Bindi, who helped us search. We found a sample of quasicrystal in a very complicated rock and there’s no question it was a quasicrystal so that could have been the end of the story, but what happened was that when we began to show this rock to geologists, or our results to geologists, they became very skeptical that it could possibly be natural. Not because it was a quasicrystal, but because it… of the particular chemistry of our quasicrystal. It had metallic aluminum in it and aluminum has a strong affinity for oxygen—so in nature, there’s lots of aluminum but there’s no metallic aluminum unless you go to as aluminum foundry. So they said this must come from an aluminum foundry, not from nature.
So that then launched a quest to try to figure out where this guy came from—where the sample from Florence came from—and over the next two years we eventually were able to show that it came from a very obscure region of far Eastern Russia, was found in the ground, was not formed in a foundry, and was actually part of a meteorite that fell there—probably about 10,000 years ago—and a meteorite that comes from the very beginning of the solar system, about 4 and a half billion years ago, so our quasicrystal’s about 4 and a half billion years old. And then I put together a geological expedition… I put together a geological expedition to go there to look for more samples, which we found, because we only had the one in the museum to begin with, and we found more and it not only had the quasicrystal but it had other new minerals that had never been seen before. And one of them is a mixture of aluminum, iron, and nickel and the team decided… so when you find a new mineral you have to write a paper explaining its properties and then you have to post a name for it and they did me the honor of calling it Steinhardtite. So that’s the Steinhardtite mineral. It’s one of the minerals found this meteorite that’s 4 and a half billion years old and that includes the first known natural quasicrystal.
How did an inflation researcher like you come to study quasicrystals?
I came to physics rather late, so when I decided I was interested in physics, I had to find out what area of physics I wanted to investigate. So what I decided to do was spend, you know, each of my undergraduate years exploring some area of science, physics rather, to decide which one I would want to choose, figuring at the end I would choose one. But what actually… I didn’t choose. Every one of those experiences led to some, you know, by some trajectory or another, to other projects that continued, almost all of them up to the present day, including spending a summer at Yale University studying, what was originally their structure of amorphous silicon—so silicon when you cool it rapidly will form a random network, and its properties have never been… were at that time and even today aren’t really fully understood, so I started on that project. That got me interested into thinking about what kind of structures, atoms, and molecules can form. Do they have to really conform to the rules of crystallography? And then again like most of you know these stories, there’s a long circuitous story—trying different things, failing, eventually led to the idea of quasicrystals.
I’m always looking around for good problems to work on so I don’t have any rules about what problems I work on, I have to… but I need an idea. So I’m always listening, to lots of different areas of science in hopes that I’ll find a good puzzle.
What would you be if you weren’t a scientist?
Hmm. That’s tough because really, that’s the only thing I’ve been thinking about. What would I be doing if I were not a scientist? Well I’d probably be teaching something about science. Yeah, I wouldn’t be a scientist but I’d probably be a teacher of some sort. At least I could… you know, I enjoy learning about it as well as doing research in it. But it’s hard for me to believe that I wouldn’t be doing research in it—at least tinkering on my own.
Maggie McKee is a freelance science writer focusing mainly on astronomy and physics. Previously an editor at New Scientist and Astronomy, she lives near Boston with her husband.
