Remember when I freaked out over how awesome outer space is and declared it Literally the Best Thing Ever? Well, Neil deGrasse Tyson spends his whole life talking about how cool space is. He is an astrophysicist, a writer of many books, an excellent Twitterer, and an unofficial spokesperson for the universe. He’s even had an asteroid named in his honor. Do you have an asteroid named after you? Yeah, I didn’t think so.
On July 4th, scientists in Switzerland discovered the “Higgs boson,” which is apparently some sort of extremely important particle. I didn’t completely understand it, but I figured if there was one person who could help me understand Higgs it was Neil deGrasse Tyson. So I called him up to learn more about the amazing Higgs boson discovery and to talk about extremely intelligent aliens, accepting the unknown, and why dark matter makes me feel terrified.
HAZEL: So, how are you feeling about the discovery?
NEIL DEGRASSE TYSON: Well, part of me, a secret part of me, wanted it to not be there at all.
Because then you’d have to completely rethink all the ideas that led to its discovery. It would have opened up all new pathways of thought.
In the history of science, there are three kinds of discoveries you can make. One of them is what you expected to be there—confirming your understanding of nature. Another one is, you don’t find what you expect to be there, so you have to go back and rethink everything. And sometimes when you’re forced to go back and rethink things you end up making discoveries you had not previously anticipated. The third kind of discovery is discovering something you didn’t expect at all. Like, who ordered that? [Laughs] The [Higgs discovery] is something we all kind of expected to be there. It’s there, it’s confirmed, and certainly worth a bottle of champagne. But it doesn’t really bring a new understanding of physics; it confirms our prevailing understanding of physics. And that’s a good thing, but sometimes when things go as you don’t expect them, major advances occur.
For example, there is a very famous experiment called the Michelson–Morley experiment, where they went to measure the speed of light in different directions as Earth went around the sun. They expected the speed to be different depending on which way Earth was moving, and it wasn’t! It was exactly the same number in every direction they moved. That became the foundation of relativity, because relativity has as one of its tenets that the speed of light is constant no matter how you’re moving. The fact that they didn’t get what they expected led to an entirely different new discovery.
So the Higgs discovery is an amazing discovery, but what would have been more amazing is if it wasn’t there at all.
Can you explain to me what the Higgs boson is, in the simplest terms?
It’s a kind of particle that creates a field. Other particles move through that field, and as they do, the field gives them their mass. Without the Higgs, nothing would have mass in the universe; and everything would be traveling at the speed of light, since all massless particles, like light, travel at the speed of light. So it’s a very powerful particle, and that’s why everyone was so excited about it.
By analogy—and I don’t take credit for this—think of a party in Los Angeles. You walk in and nobody knows who you are. So you can walk in and out of that party without any resistance at all, because nobody’s going to be hanging around you. But the more famous the person, the more people will recognize them as they walk into the party. Then other people will crowd around them and interfere with how fast they can move. So the most famous people that walk in can barely move at all. The Higgs field is just like what goes on at an L.A. party: some particles have high mass and some particles have low mass. More-famous people have more “party mass.”
How exactly did they discover the Higgs boson?
Any time you build an accelerator that can create pockets of energy higher than anyone has created before, you’re going to discover something. It’s not conceptually different from the days of the great explorers of the 15th century. They go where the maps haven’t been drawn yet, so they’re going to discover something. The accelerator in Switzerland, CERN, probed matter at higher energies than ever before.
I heard that the Higgs can help explain what “dark matter” is. What is dark matter?
Five sixths of all the gravity we measure in the universe has no known origin. It’s a mystery. We can track the black holes, the gas clouds, the planets and stars, and all the atoms. When we do, it accounts for one sixth of all the gravity in the cosmos. We don’t know what’s causing the rest of the gravity, so we’re calling it “dark matter.” But we don’t even know if it’s matter—that’s just a placeholder term. And then there’s another mystery: a pressure in the vacuum of space that’s operating against the wishes of gravity and making the universe accelerate in its expansion—we call that “dark energy.” But we don’t even know if it’s energy. We don’t know what it is. If you add up dark matter and dark energy, it comes to 96 percent of everything that drives the universe.
That’s so scary!
It is completely spooky scary. If you look at a pie chart of what we know and understand in the universe, it’s a four percent slice of the pie. That other 96 percent is completely mysterious to us.
So any time you make a discovery in physics, you hope that it’ll help you understand other things that you don’t understand. The solution to one standing problem provides the solution to other longstanding problems that you thought were disconnected.
Can the Higgs particle directly define dark matter?
It’s a start. The fact that it gives mass to things is useful. If there’s some kind of particle that it’s giving mass to that we can’t otherwise measure in our normal way, maybe that’s insight into dark matter. It’s more a hope that it will help us understand dark matter than an expectation.
Can Higgs help determine if there are other dimensions or parallel universes?
That I don’t know. I don’t think so. String theory requires other dimensions and other sorts of understandings of cosmology, but all the experiments [regarding other dimensions] are being conducted in our dimension! [Laughs] There is not some portal to a parallel universe going on in Switzerland—you can rest peacefully knowing that.
But the people who like taking you to higher dimensions are doing a very natural thing. They’re saying, “Who is to say that reality is limited to three spacial dimensions?”
Consider this example: When we built telescopes, starting from Gallileo onwards, the telescopes were really extensions of our eyes. They enabled us to see things farther away and brighter and better. So we said, OK, that’s the universe. Well, consider the bias that that represents. It’s so biased that we didn’t even know to ask if there were other kinds of light out there that were not visible. It would not be until the late 1800s or the early 1900s that we said, wait a minute—there’s some other kind of light out there that’s below the red part of the rainbow, the red part of the spectrum. We can’t see it with the eye, but it’s there, so let’s name it: infrared. As you continue to flesh out the spectrum you find other bands, like radio waves and microwaves. It wasn’t until the 20th century that we could observe the universe in bands that the human eye can’t see. Without these other bands, we’re practically blind. Except we don’t know that we’re blind, because we didn’t even know there was another way to think about the universe.
So to imagine higher dimensions is a very natural thing to do. Just because your senses have their own way to measure the world doesn’t mean the actual world can be plumbed with those senses.
I wrote an article in March about how space is really awesome. I mentioned that the Kepler spaceship has spotted potential planets that might be habitable. Do you think there are life forms as developed as humans living on those planets?
Well, that assumes that humans are some measure of development. It may be that we’re actually quite primitive compared to other species out there.
In fact, you could argue that the reason that we haven’t been visited is that [aliens] have already observed us and concluded there’s no sign of intelligent life here. I mean, if you have a spaceship that can cross the galaxy, you’re way smarter than us, because we have nothing that remotely approximates that. So why would we assume that we would be interesting enough that they would want to study us? That’s just humorous. How interested are you when you walk past a worm crawling on the ground? Do you ever say, “Hey, I wonder what that worm is thinking?” I’m sure you’ve never had that thought in your life. You might have even just stepped on the worm. So, imagine a species with that intelligence gap interacting with us. They could not come up with a stupid enough thought that could stoop as low as to fit inside of our brains. [Laughs] Just think about it!
What are the most common misconceptions that people have about space?
Number one is that they think the space shuttle and the space station are far away.
Are they actually close to us?
Oh, yeah. If you take Earth and shrink it down to the size of a schoolroom globe and you shrink everything else down to that scale, and then you ask: how far away is Mars? Mars would be about a mile away. How about the moon? Thirty feet away. How about the [NASA] space station’s space shuttle? Three eighths of an inch above the surface of the globe!
We’ve convinced ourselves that that’s space travel, but it’s not. It’s just above the surface. The atmosphere of the Earth is not much thicker than the shellac on that globe. The people they say go into space—they go 100 kilometers up, these space enthusiasts; they’re coming just above the shellac. You could drive from Earth’s surface to the height of the space shuttle’s orbit in four hours.
I honestly had no idea these things were so close. Now I feel stupid.
People will ask me, “When are you going into space?” And I say, “Give me someplace to go and we’ll revisit that conversation.” I’m destination driven. Take me somewhere.
So, I follow you on Twitter—
Oh, thank you!
I think if real female scientists are interviewed, their enthusiasm will be manifested in the interview. It’ll just come across. If you look at the second video I tweeted about, the a cappella song group, they love their work!
What I like about that video is that they show that sometimes they don’t always get a result and it takes a long time to get things back. They’re honest about it! It’s not all flashy. One of the lines, which is what all of us feel, is “I don’t care what income my work brings.” So many students go to college to get a job that pays a lot of money, and they’re linking their happiness to their money, not to their actual profession. When people say to me, “Oh, when are you taking your vacation?” I say, “Vacation from what?” I’m on vacation when I’m doing my work!
I also think that you shouldn’t always presume that you need to have a woman be the role model for a girl. Because that presupposes that a woman had to have occupied a profession that you’re interested in before you could ever be interested in it. That’s actually limiting your possibilities rather than expanding them. If you require a role model who is your gender, you will never enter a field where there aren’t any women. I think we’re far enough along with girls that they can see a male scientist who loves his work and not say, Oh he’s a man—I can’t do that. They’ll say, Oh, he loves what he does, and I want to do that too.
When I grew up I assembled my role models à la cart. I wanted to be an astrophysicist. If I tried to find a role model who grew up in the Bronx with my skin color who was an astrophysicist, I would never have become an astrophysicist.
The recipe for success overlaps from one profession to the other. It’s hard work and determination and focus. That’s true no matter the profession. So your role model can be anything.
Why is science so dominated by men?
That’s not true in the biological sciences. For example, the number of women in college majoring in biology might be 50 percent by now. Veterinary medicine is almost 100 percent women. So there are science fields where women are not underrepresented. I’m old enough to remember that there used to be no female medical doctors, ever. Not on sitcoms, not on dramas, not in movies, nowhere. Now, women are probably half of all doctors. It’s true that women are still underrepresented in the deep physical sciences, like physics and astrophysics.
All of this is not to deny that there are issues in the workplace, but that happens in every workplace. There’s always that shithead guy. [Laughs] There is! We know these people—we saw them in high school and they just become adults, right? They don’t typically change. There are a lot of people thinking about this [gender inequity] problem, and there’s still more progress to be made.
Do you ever get really overwhelmed by the universe? How do you cope with not knowing everything about it?
The not knowing is the actual attraction of it. So many people only want answers. To be a scientist you have to learn to love the questions. You’ll learn that some of the greatest mysteries of the universe remain unanswered, and that’s the fun part. That’s the part that gets you awake in the morning and running to the office, because there’s a problem awaiting your attention that you might just solve that day. You have to embrace the unknown and embrace your own ignorance.
So I don’t get overwhelmed, because I don’t think about what I don’t know as oppressive to me. If you think of it as oppressive, or if you have a measure of your ego that’s larger than nature provides for you, then it’s possible that you could end up quite depressed, seeing how small we are on Earth, [orbiting] around an ordinary star in an undistinguished corner of our galaxy between a hundred billion other galaxies. That’s upsetting to some people, because it destabilizes their sense of self-worth. I would assert that it’s not inherently destabilizing to learn this—it’s only destabilizing if you walked into the room with an unjustifiably high ego to begin with. If you come in with a humble enough ego, all of this is kind of enlightening instead of depressing.
I think whenever people finish their formal education, they say, “I’m done learning!” And then they want to make money off of what they have learned. Many people willingly stop the growth of their own minds! Nobody else forced that; they said they were done learning and they didn’t buy any more books or make discoveries or turn over the rock or see what’s beyond the valley. But fortunately there are enough people in society who continue to do those things—and those are the folks that shake the world. ♦