Science Friday - Ocean Conservation, Dark Matter Hunt. June 8, 2018, Part 1

Episode Date: June 8, 2018

Planets, stars, and physical “stuff” make up a tiny fraction of the universe. Most of the universe's mass is instead invisible dark matter, which makes itself known not by luminance, but by its gravitational influence on the cosmos. The motions of galaxies and stars require dark matter to be explained. Yet despite decades of searching and millions of dollars spent, physicists still haven't been able to track down a dark matter particle. In this segment, physicists Jodi Cooley and Flip Tanedo, and Gizmodo science writer Ryan Mandelbaum talk about how experimentalists and theorists are getting creative in the hunt for dark matter. Plus: Earlier this year Brazil made headlines and received accolades from ocean conservation advocates for turning 900,000 square kilometers of ocean in its exclusive economic zone into a marine protected area. That’s the good news. But the question remains: Does that 10 percent really need protecting? Natalie Ban, associate professor at the University of Victoria, tells Ira more. And Tanya Basu, science editor at The Daily Beast, joins Ira to talk about advances in breast cancer research and more science headlines in this week's News Round-up. Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.

This is Science Friday. I'm Ira Flato. A bit later in the hour, we'll check in on the hunt for the elusive dark matter and why it's so hard to find. Well, it is dark, but there's much more to the story. First, last week, researchers reported in the New England Journal of Medicine that many women with breast cancer may be able to avoid chemotherapy and maintain the same chances of survival as women who do get chemo. And that may mean an easier treatment regimen for about 70 percent. of women diagnosed with the most common type of breast cancer. Tanya Basu Science Editor at The Daily Beast is here to talk about that research and other selected short subjects in science this week. She's on New York Studios. Welcome to your first time on Science Friday. It is my first time. Thank you for having me.

You're very well. Let's talk more about this breast cancer news. Many people may not need chemotherapy. Yeah. So the study goes back from 2006, and there were thousands of women, 10,000 women, I think. that were studied. They're, you know, middle-stage cancer. They all get surgery, and then they get put in two different paths. They either get endocrine therapy or they get chemotherapy. Turns out the women who went through endocrine therapy basically the same results as those who went

through chemotherapy. And now researchers saying, why are we putting them through all this radiation if it's not necessary? So that sounds like it's great news because chemotherapy, as you say, can be very difficult. Very toxic. And, of course, endocrine therapy has some drawbacks as well, you know, hormonal imbalances and stuff, but it's still not as bad and, you know, as just physically hard. So this is for the great majority of women? Yeah, with middle stage breast cancer. Wow.

That's great news, thanks. Yeah. And let's go on to some other news. There's been a big potential immunotherapy advance. Yeah, so a 42-year-old woman from Florida went through immunotherapy, which is using your own body's immune system. This is even better than endocrine therapy. Better than chemotherapy, which kills you.

stuff. Exactly. And so she's using her own immune system to basically fight cancer. She was given three years to live. It's been two years and she's cancer-free. So very promising. We don't really know yet if this is going to be something we can keep advancing, but definitely something to look into. Because only a minor number of people who get immunotherapy actually respond positively, right? Yeah. So it's in its early stages. Yeah. But the people who do respond really respond well. They respond beautifully. I mean, look at this. curative cancer. Wow, that's really good stuff to follow.

Let's go on to fast forward to backwards. Let's go. Last week we talked about the seasonal hurricane forecast for the months ahead, but there is a new study saying that the future outlook for storms could be stormy. Oh, yeah, very stormy. So these researchers took 22 hurricanes and then simulated them in 2100, the year 2100, when climate change is supposed to make the world nine degrees warmer. And they found it's going to be pretty bad.

So winds are going to be 6% faster. Rainfall is going to be, there's going to be 24% more rain. And 9% slower movement of hurricanes. That sounds good, but it's actually bad. When a hurricane moves slowly means that there's just more, you know, potential for damage. Wow. So are the winds in the hurricane going to change, how they work or they move? They're going to be probably much more violent just by nature of how slowly the hurricane.

hurricanes are moving. And so that's really, you know, some really interesting yet scary stuff coming ahead of us. Yeah, because we've had one heck of a winter with the Northeasters in the wintertime. And now we're going to see about the hurricane. And we're only one weekend to hurricane season. Wow. So is it possible then? And, you know, I remember in the summertime, I remember seeing because of climate change. Yeah. I remember Australia, I saw news report that Australia had to change the color of its map for heat because.

because it didn't have a number high enough to go past, what, about 120 Fahrenheit? Yeah, so there's actually some people who are proposing six categories of hurricanes. You could have a Category 6 hurricane. We're at 5 right now. But, you know, there's some controversy and backlash at this because Category 5s are already dangerous, and a lot of people don't really respond. They're like, no, we're going to stay here. We're going to keep our house and everything.

There's a 6 that comes into play. Are people going to be like, oh, if it's a 6th, It's a five. It's not as bad as a six. I'm going to just stay, which is faulty thinking, but, you know, it's human behavior and could be dangerous. Speaking of dangerous, let's talk about the volcanic eruption in Hawaii. But I now, there's been in the news an eruption in Guatemala. Any connection between the two?

No, no. I talked to a volcanologist or volcanologist. I'm not sure how you pronounce that. Either way. Yeah. Well, I talked to an expert. And she was very much like, absolutely not. two different plates, nothing connected.

There's 25 volcanoes a day, and you never hear about those. So not connected at all, but needless to say, extremely violent volcano that just erupted in Guatemala. Over 70 people dead, many missing. It's just really rough. And their volcanic eruptions are for a different reason than go on in Hawaii, right? Yeah, so the Hawaii one, what's in the news, you'll see these really spectacular images of lava and fire, basically. What's in Guatemala is a little bit different. So it's called pyroclastic density currents.

If you say so. I know. I'm just making this up right now. Believe me. No, and it's basically this volcanic version of an avalanche of rock and 1,000-degree gases, and it's very toxic. It moves faster than a supersonic airplane. And you see these videos of people, you know, shooting video of it coming down,

and many experts are like, why are you doing this? This thing is moving at 450 miles per day. it's going to just get out of there. Just leave. So it's very dangerous. Guatemala is in its rainy season right now. So mud slides to come as well. Let's talk about probably a lot of people's favorite story of the week,

and that's the peacock attacks in British Columbia. Yeah. What's going on there? All right. So there was a farm, and the farm got closed, and these peacocks were just sitting in a tree. Some guy cut the tree. And the peacocks went loose.

They go and see these cars that are super shiny, see their reflections, and instead of their reflections, think of them as their rivals and hack at the cars. And so they're denting up the cars? They're denting up all over the car? They're denting up all those cars. And how do they stop? Why do they stop? After a while, they can't see themselves, so they say, hey?

There are reports of them destroying completely front panel, back panel. Like, they just keep going until they don't see the reflection anymore. So they're very determined. And they can't do anything about the peacocks. No, no, no. They were originally reported to be screaming at night, which is why this guy cut down the tree. Right. Right.

But maybe it was better for them to scream. But he moved out of town, right? I mean, at this point, you should. Great story. Nice to have you, Tanya. Thank you. Tanya Basu is an editor at the Daily Beast here in New York. Now it's time to play Good Thing, Bad Thing. because every story has a flip side.

Now, you may remember earlier this year when Brazil turned a 900,000 square kilometer swath of open ocean into a marine protected area, and it's not just Brazil. By the year 2020, nearly 10% of the world's oceans should be protected, thanks to a formal commitment made by many world governments to ocean conservation. That's the good news.

The question is, are we protecting the wrong places? Here to tell us the good and the bad news of the New Ocean Conservation effort is Natalie Ban, associate professor in the School of Environmental Studies at the University of Victoria and British Columbia. Dr. Ban, welcome to Science Friday. Thank you so much, and happy oceans day to you. Happy oceans day to you. So the government signed on to protect 10% of the world's oceans by 2020. How are they doing in terms of meeting that goal so far?

So far, we're not quite there yet. Globally, we have about just over 3% of the oceans protected, of which about 2% is highly protected. So we're still a long ways off that 10%. But that target has really energized a lot of countries to try to meet the deadline by 2020 to protect that percentage of their oceans. And there are some countries that have really gone a long, long way towards it, much more so than what would have been expected. So, for example, Palau, an island nation, has protected about 80% of its ocean estates, of its exclusive economic zone. And earlier this year, there was a big announcement that the Seychelles, another island country, did a big debt-for-nature swap. So they protected a large portion of their marine area in return for getting some of their debt forgiven.

Now, that's the good news. What is the bad news besides the fact the U.S. is not a lot? a member of this agreement? Well, the bad news is that this target by the Convention on Biological diversity includes in it that 10% of the ocean should be protected. And it's got a bunch of other stuff that's actually really important, like that those areas should be important to biodiversity, that they should be equitably managed, ecologically represented, and so on. But what countries have latched onto is just that 10%. So you mentioned the example of Brazil. Brazil is, is protected in total

about 26% of its ocean area. And, you know, that sounds fabulous, but the two places that it added are way offshore. Nobody goes there. They're not currently actually threatened. And the problem is that some countries are playing this political game

of trying to meet that target without actually protecting the places, especially near shore, near people that really need the protection. So how do you overcome this then? Well, in part, we need to, commitment to really protect the oceans from the threats that exist to them. So it means that we can't just protect the large offshore area, some of which are really important to protect.

We just need to make sure that protecting those large offshore places doesn't come at the expense of also doing conservation in places that are near shore, near people, and so on. So it's really important to look at these other aspects of this target, not just the percentage, but if we represented all of our marine ecosystems. So say, for example, coral reefs and rocky reefs and sandy areas and estuaries, and ensured that 10% of all of those ecosystems and habitats were protected, then just protecting that giant offshore area wouldn't actually help meet the target as much as it does right now, and we're only looking at that percentage target.

Yeah, so we have to do the hard work, too, where it's hard to, not just the easy stuff. Well, that's exactly right. It can be politically expedient to protect places where nobody goes. And it's kind of equivalent to on land where, you know, there's the phrase, we just protect rock and ice, the high mountain tops with glaciers that are beautiful, but don't necessarily have all of those threats. That's not the places that are being developed and in the ocean that are being fished or mined or have, you know, coastal development and so on.

And yes, I think it's important to also protect those remote, wilderness, if you will, places. But we can't only do that. We need to also focus our efforts on the more threatened places because that's really where biodiversity is hurting. That's where our fish stocks are threatened. Our mining is taking place and so on. Dr. Ban, thank you very much for taking it down to be with us.

Natalie Ban, the University of Victoria in British Columbia. We're going to take a break and talk about dark matter, one of our favorite topics. Why can't we find any? It is dark, but we should be able to see some of it, shouldn't we? or detect it some way. We'll talk about it after the break. Stay with us.

This is Science Friday. I'm Ira Flato. It's invisible to our telescope, but makes up more of the cosmos than the stuff we can see, like planets and stars. In fact, we're coasting through clouds of it right now. Can't see it, though.

I'm talking about, of course, dark matter. That's the theory, at least, because no one has been able to find out what the matter is made of. Astronomers have a very strong hunch it is there due to the motions of galaxies and stars but particle physicists still haven't been able to directly detect any of it a fact that's got a few physicists wondering if so-called dark matter is actually just a

discrepancy in our theory of gravity time to rewrite the rules perhaps some of them say science writer my Ryan Mandelbaum is energized by all of this writing about the quandary in Gizmodo and he's here to guide us through this tangled web of mysterious dark matter. Welcome back, Ryan. Hey, Ira, how's everything going? I know this is one of your favorite subject. I love dark matter.

All right, give us, let's go through the layout the land for us. What's going on with the search for dark matter, why, you know, what it is and why we haven't been able to find it. Sure. So I think that the great, the biggest summary is just no matter where we look in the universe, things act bigger than they look. Galaxies seem to rotate a little too quickly, well, way too quickly around their edges. The entire large-scale structure of the universe looks like there should be around four

five times more mass than there really is. And so we've got, you know, all of these astronomical observations that tell us that, and a lot of these little hints that tell us that it should be there, and then searches on the, you know, both at the Large Hadron Collider and this new experiment or this newly, these new results from this experiment called Xenon, which have not found it yet. And so it's interesting times, and there are folks who, you know, there are people. people who are concerned. They're coming up with new ideas. People have predicted it should be things called

wimps and things, right? They've given the names to particles they think might make up the dark matter. Yeah, so probably around 10, 15 years ago, physicists might have told you that dark matter and wimps were synonymous. What's a wimp? A wimp is a weakly interacting massive particle. The best way I could sort of explain it is it's like a ghost.

A wimpy ghost. Right. It's got mass, but it just passes through matter without interacting with it very strongly. So if you were detected, it would be a really slight nudge. And there are a couple ways you can either make it in a collider or maybe you could just detect it with a really sensitive experiment here on Earth, but we haven't found them yet.

Oh, wow. And, I mean, they were really well motivated. I mean, people, there was good reason for people to think that wimps were the dark matter. It's called the Wimp Miracle. But the sort of most obvious answer to what the Wimp would be seems to not be the answer right now. So maybe the wimps are we're weirder than we thought. I like that alliteration.

That's good. And you talk to some theorists who might say it might be time to give up the hunt and throw out the rules of gravity, start over again? So there are a couple of ideas that folks have come up with that they posit that maybe dark matter is just requires a rewriting of the rules of Einstein's theory of general relativity. So there's rules of gravity. I will say that these theories are early on in their development and don't explain everything. and I think there are a lot of folks who might even be mad at me for bringing them up, but these people have a seat at the table, and people are wondering what, you know, people are asking them about their theories,

and they've got ideas. Well, it's because, you know, like with string theory, after a while, if you can't find the evidence, science is all about the evidence, and as you say, they haven't found the evidence of these particles that sometimes you have to give up on. Sure, so, I mean, there are plenty of other theories as to, maybe if it's not a wimp, I've seen simps, which would be strongly interacting massive particles.

Axions I've spoke to you about in the past, which would solve another problem in particle physics. Named after a laundry detergent. It is named after a laundry detergent. And axioms are one of my favorite. I think they're really punk rock. But we can get into that later. So there's all sorts of ideas with various motivations.

And then again, there are folks who say, well, let's just come up with a new theory. Well, we have a couple of those folks who are talking about different ideas and how we look at it. I want to bring these voices now. Flip Tornado is a theoretical physicist and professor of physics at the University of California, Riverside. Welcome.

Hi, pleasure to be here. Nice to have you. Jody Cooley is an associate professor of experimental particle physics at Southern Methodist to you. That's, of course, in Dallas, and she joins us today from a big dark matter conference in Santa Barbara. Welcome to Science Friday. Thank you. Hi, Jody. Nice to have you.

Let me begin with you, Jody. Now let's talk about that big meeting of the minds and conferences. California. Have you all figured out where it's hiding yet? Well, of course not. If we knew where it was hiding, if we knew where it was hiding, somebody would probably be going to Stockholm. Yeah, to pick up that, yeah, metal. Yeah. To pick up that Nobel Prize, that's true. So, yeah, so there has been, actually there have been two different programs that have been going on here

at the Cavalry Institute for theoretical physics here in Santa Barbara. Barbara. One was called Hepfront, and these were some particle physicists who got together, and for two or three months were coming up with some different ideas about how perhaps, you know, and this is not throwing out the idea of wimp, of wimps, possibly being the dark matter. There's still a lot of possibilities for wimps being dark matter. But, you know, it's sort of opening up our minds a bit more and saying, you know, what if wimps aren't the dark matter? Are there other options that we should be looking at? Are there other types of particles we should be exploring and are there other experiments we should be doing?

And so they spent some time, you know, thinking about these ideas and talking about these ideas. And there's a program that's going on now. It's concluding in a couple of weeks that was going on for two months in parallel with this program called about, cold dark matter and this is more primarily thinking about from the astrophysics perspective and so these are astrophysicists and astronomers who are gained together and they're kind of looking at it from the perspective of astrophysics and astronomy and kind of looking at the big picture and looking at what gravity can tell us and looking out at the kind of looking into the sky looking at

things like Ryan was saying looking at large-scale structure looking at the cosmic microwave background these are the photons that come from us from, you know, the very beginning of the universe. They actually tell us quite a bit about dark matter as well. And looking at galaxies, looking at galaxies that merge together. They don't tell you what it's made at of, do they? They don't tell us what it's made of, but they can, you know, help us complete the picture. And I think, you know, that's sort of, you know, important.

Okay. Let me bring a flip in. You're on the theater. I'm going to say theater. Same thing. The theoretical side of things. Has the concept of what dark matter, has it changed over time? It has definitely been evolving quite a bit over the past 10 years.

And I'll go out in a bit of a limb here, and I'll say that the simplest garden variety Wimp theories are basically dead. And it was Jody and her collaboration and other collaborations like hers that actually killed it over the past 10 years with their fantastic experiments. And while a lot of people see that as being something where, oh, we're not sending somebody to Stockholm this year, does that mean that we kind of should feel bad of ourselves? This has actually been a really quiet revolution on the theoretical side where it's led to many exciting new ideas about how we are forced to think about what dark matter could be. So before we, I want to know how dead the Wimp is. I know a lot about the neutrino floor and there's all sorts of experiments that are continuing to look for. for it. So, I mean, when will it be that we actually say the Wimp is dead? Oh, great. That is an excellent point. So I am definitely opening myself up to attack here.

Wimps can come with various bells and whistles. You can dress a theory with other features to make it a little fit a little bit better with the data. But I think the type of thing, so Ryan, in your fantastic article, you mentioned a review article in 1996. I talked about, oh, dark matter is definitely this type of particle coming from supersymmetry. The things that people were talking about in the 90s, if you grabbed any physicist from the 90s and told them, put your bet on what are the properties of the WIMP, I would say 99% of the time the numbers that they would give you are now excluded.

Wow. Do you think that... Yes, go ahead, Jody. Sorry, but I think one of the things that you have to keep in mind, Flip, is that, you know, when we talk about the WIMP, it's actually a classification of particles. right? It's weakly interacting mass of particles. And I think there are a lot of types of particles that fit into that classification. Kind of like when you talk about

people, right? They can, people come in a lot of different shapes and sizes. Wimps also come with a lot of different cross-sections and masses, right? There's a lot of different properties that you can give a particle and it can still be called a WIMP. And I think that's what gives the WIMP a lot of flexibility and what makes it very difficult to completely rule out. you're not ready to clap I'm just thinking the wizard of ours and the wimp being dead but you know

well you're fighting very hard for it aren't you I think it's important yeah yeah Jody Jody you're absolutely right I wouldn't say that I'm no yeah I'm not fighting hard for it I think we have over the last decade and we have ruled out

a tremendous number of ideas about what a wimp could be but I think to say that it's completely that is not a fair statement. Let me move on from the wimp to new thinking about physics. And Flip, do we need new ideas? You're a young

astronomer, a physicist, theoretical physicist. Do you bring new ideas to the table that your, perhaps your forefathers, I might say, might have not been accepting of? Oh, gosh, I hope my advisor isn't listening. Yeah, so what's really interesting, I think that

me and probably the, a lot of my colleagues, we see ourselves as refugees from the Large Hadron Collider. So we are a group of theoretical physicists who kind of cut our teeth in our PhDs building new theories for the Higgs boson. And all of the promises of the 90s, the theories of the 90s, supersymmetry, extra dimensions, all these weird ideas that we kind of sold ourselves, you know, drinking the Kool-Aid that when the Large Hadron Collider turns on, we're going to find all these new particles and explain everything about the Higgs. And then come 2013, when we're all writing up our dissertations, the LHC discovers the Higgs, and it turns out to be the most boring

possible thing from the point of view of new physics. And I think a lot of the theorists of my generation kind of had a bit of an identity crisis where we had to reevaluate what is the most pressing question in particle physics. And not only what is the most pressing question, but what is the most pressing question that we actually have a shot at answering experimentally in our lifetimes? And so I think we've all brought a kind of toolkit for how do we approach models of particle physics to this new arena of dark matter physics. What about the rejiggering of our ideas about gravity? Let me ask Ryan about this too. Do we really have to rethink our ideas about gravity because it's so key to understand the universe if we

don't know what the dark matter is. I think there's a couple of people who will tell you that perhaps we need to rethink the ideas of gravity. And I think I'd like to leave it up to Jody to tell me what she thinks about that as well, because she's at KITP, so she could get you a bit of what the people there are thinking. But there are two theories that I talked about in my piece recently. One is modified Newtonian dynamics or Mond. The other one is emergent gravity.

These are really, these are like ideas that maybe there are rejiggering of the laws of physics that could perhaps explain things like why galaxies rotate too quickly around their edges. Again, early on. Well, okay, Jody, what do you make of this? I think the way that Ryan described it is very fair. These are ideas. You know, they're not fully developed theories.

Theories are hypotheses. They've been tested. Usually when we have a theory, it's complete. You know, ideas are great, I think, that right now, there's a lot of evidence out there that sort of points to the idea that dark matter is a particle. And if I were a betting person, I would put my money on dark matter being a particle. However, you know, we've been searching for dark matter as a particle for a very long time now, and we haven't found it. And, you know, I think it behooves us to entertain the idea that perhaps, perhaps we might be wrong. And so we should leave a little room in our minds for the idea that there may be some other ideas and some other possibilities out there.

But these ideas of modified gravity, emerging gravity, you know, they're very, they're not very well developed in that they can explain. some dynamics that we see in some of these systems, but they really don't explain some of the strongest evidence that we have for particle dark matter. They don't explain things like the cosmic microwave background, which really, you know, strongly tells us and gives us a lot of real strong evidence, you know, for dark matter. And when we take our whole, you know, sort of everything that we have

from astrophysics and astronomy and we put it together, you know, just saying dark matter is a particle. that sort of solves it all. Okay, let me just give it. So I think that it's good. Yeah, I'm Ira Flater. This is Science Friday from WNYC Studios. Lively discussion about dark matter with my guest, Ryan Mandelbaum, Flip Tenado, and Jody Cooney, our number 844-724-825-5.

We're close to the break, but let's see if we can get a phone call from a listener in here. Let's go to Bill and where is it, Plasterville, California? you? Hi, Bill. That's it. How are you? Fine. Go ahead. Well, my question is, when you take a look at the universe from what we know about it, it changes all the time and expands, and we get to a point we think, well, we know everything now, or we know pretty much everything, and then we look back later and we realize how little we really knew. And Dark Matter, just by the name of it, suggests that that's sort of like what that's going to be. I mean, is it going to be, are we going to be 20 or 50 years from now? Are we going to be able to look back? Or are we going

know definitively what dark matter is and how it fits into the universe, sort of like the Big Bang Theory, how, you know, for up until 100 years ago, we had no idea. And then Einstein even said, no, that can't be true. So, I mean. Good question. Let me get an answer. We thought the ether existed once, too, didn't we, Dr. Cooley. Are we going to know 50 years from now what it is? I sure hope so. I'm sure hoping that within the next five years that we know. So right now, The United States actually has this portfolio of experiments that it's funding to look for the dark matter. And these experiments, there's three of them. One of them is called the LZ experiment.

It stands for Lux Xenon. And this experiment is looking for sort of, we call it, high mass dark matter. And so this is dark matter that has, or it's most sensitive to dark matter that has masses sort of higher than 10GEV. so that's 10 times the mass of the proton. It's also funding the experiment that I work on, which is super CDMS. These are, is most sensitive to dark matter that will have masses between sort of 1GV and 10GV. So that's 1 to 10 times the mass of the proton. And so these actually are dark matter that are more aligned to the kind that Flip is talking about,

these sort of new ideas of dark matter. And then we also are funding a third tech. of experiment called ADMX. And this is actually this axi on dark matter that Ryan likes so much. And so we actually have a really big portfolio. Okay. Looking for dark matter. Sorry.

No, no, I'm sorry. People hate it when I do it, but I have to do it. We have to pay the bill. So you're going to all be back. We're going to talk more about this. What Dark Matter is made of? Our number 844724-8255. You can also tweet us at SciFri.

As I say, we'll be back in the light after. this break. Stay with us. This is Science Friday. I'm Iroflato, and we aren't talking this hour about the hunt for dark matter, which they say, well, makes up 25%? Something about 25% of the universe? Ryan? I'm with Ryan Malthabom, science writer at Gizmodo, and there are all kinds of new ideas and new theories. And of course, we're not talking about dark energy now. Let's just get that out of the way. That's a different... Oh, that's different. We're just trying to get it. We barely understand the 4% of the universe that we're made of,

and now we're trying to get to the 20-something percent that's dark matter, and then there's dark energy. We don't have time for it. Another show for that. My guest, Ryan Mandelbaum and Flip Tenato on Jody Cooley. And, Flip, let's get in, let's put our hair-hirting helmets on. Let's talk about paradigm shifting ideas. For example, Ryan talked about in his article the sterile neutrino.

What is that? And what other paradigm shifting ideas can you think about? Iron watch dark matter dead. Yeah, so the sterile neutrino, it's kind of a natural idea to think about for dark matter because we know in our universe there is such a thing called the neutrino, which is a really weakly interacting particle that rarely interacts with ordinary matter.

So for a long time, people thought that either the neutrino or some cousin of the neutrino could be, the dark matter. That didn't quite pan out, but to this day, there are variants of those types of theories, and one of the forerunners is called the sterile neutrino. This has picked up some interest recently because of some astrophysical signals, looking at this 3.5-KV gamma ray line, which some people really think could actually be the first possible signature of sterile neutrino dark matter.

And so what other ideas, you know, just ideas, and I'm not going to call them theories because Dr. Cooley will get angry at me. So what other ideas are out there? So Ryan mentioned a couple, strongly interacting massive particles, primordial black holes. One that we're really excited about at UC Riverside is self-interacting dark matter. And so this is kind of a cousin of the wimp where you have a dark matter particle that actually has its own dark forces. Say that again? Yeah, so this is a new particle.

I'm listening to Star Wars here. Exactly. It's exactly what it sounds like. So there's just like visible matter can interact with itself, meaning protons interact with electrons to form hydrogen. You could posit that maybe dark matter also talks to other types of dark matter. And maybe you get some weird, complicated dark matter interactions that we would never directly see because all of this stuff is dark,

but this could actually affect the way that the, that dark matter clusters in the universe. And this might be something that we can see from tracing the visible stars that we can see from our telescopes. I mean, if you think about, if dark matter is a thing and it's five times more

than the amount of mass in the universe, then it's almost naive to think that dark matter is just a single particle, right? Absolutely. Wow. You know, there are a lot of people, a lot of tweets that I want to just cover this because a lot of them coming in. We want to talk about the multiverse

explaining the same effect that we're attributing to dark matter. Is that possible? That's a little bit more out there. And so I think one thing to be said about this idea of, we haven't found dark matter yet, so maybe it's time to restart and find some completely new paradigm

and throw away this idea that's some new particle. This is actually, it sounds very nice because it sounds like, well, there's this complicated thing that we don't understand, and we're making these very convoluted theories to explain it. Why not just start from scratch? Actually, believing that dark matter is a new particle is really the very conservative thing to believe.

And this is because, in addition to the rotation curves that Ryan very nicely explained earlier in the episode, we see all sorts of evidence cosmologically and astrophysically that this thing that is clustering in the center of galaxies really walks like a duck, swims like a duck, quacks like a duck. it has to be a new particle. Now, could it be modified gravity? Could it be something weird from some very evolved string theory? This is all possible. And we actually learn a lot from reading those papers.

But right now, it is the most conservative thing to say that there might be a new particle that we just have not understood. Let me go to the phones to Modesto, California. Hi, Lynette. Welcome to Science Friday. Hi, thank you so much. I have a question about technology, basically. It seems like in the search for the Higgs or for gravitational waves, the theory was there, but you had to wait for the technology to catch up.

Is it possible, is there some dream machine that you could build or some dream experiment you could build that you could build if you weren't limited by current technological standards? Good question. I've never heard of physicists say no to that. Question. Well, let me ask Dr. Cooley, what do you think? Is the technology there, or is it possible or impossible to build something big enough that detect? Yeah. So I've actually heard Catherine Zurich say that we're actually in a situation now where theorists are trying to catch up to the technology when it comes to searching sort of for the low-mass dark matter. Do you think that's fair flip? That I would completely agree with, yeah.

Explain that a little more. work, Dr. Kool. So I think, so it actually turns out that the technology that I work on, the CDMS, or the super CDMS technology, we call it now. So CDMS stands for cryogenic dark matter search. For a very long time in the field of dark matter searches, my experiment was one of the leaders in the field of looking for these dark matter wimp particles that, you know, had masses, 10 times the mass of the proton.

And then the xenon, these liquid noble technology. the xenon technology sort of kind of overtook us in that region. And so we adapted our technology so that we could start looking at these very low-mass regions. We could go to these lower mass regions, and the technology developed that we could look for lighter mass dark matter particles if it was that they could be interesting. And so we kind of turned to the theory community and said, is this an interesting region to look in? And are there ideas for dark matter particles that could be interesting in the space? And I guess that's where, you know, Flip and his colleagues sort of had to get to work.

Right. So basically. And so maybe Flip would have more safe. I guess just to make sure my audience understands, these experiments are basically just big sort of sitting there waiting for something to vibrate through them. And right now they're ruling out some of the bigger stuff. but then the theorists haven't come out with a way for them to rule out the smallest stuff, is that right? Or to look for the small stuff? Yeah.

Yeah. The explosion over the past 10 years, and what's really remarkable from the physics side, is that particle theorists used to kind of go off and do their own thing, sit in their coffee shops and write their papers. Now more than ever, they're actually playing a much more active role in communicating actively with experimentalists and trying to brainstorm new ways to look forward. dark matter particles that behave unexpectedly. And one of the directions here has really been to talk to condensed matter theorists or condensed matter experimentalists who work on novel materials. Some of these include superconductors or two-dimensional materials where these are ideal for looking for dark matter that is lighter than the typical wimp.

All right, let's go to the phones. Nathan in Verona, New Jersey. Hi, Nathan. Hi, thank you for taking my call. I get a question here. So what we, as technology goes, advances, we can continually see and learn a lot more. So think about flower. When we look at it, all we see other colors, but then all of a sudden they start looking at flowers with UV lenses, and all of a sudden they see all these new patterns.

When we look up the sky, all we can see is with our eyes is what's available in visible light. But then we have new technology. It now can see X-ray and all these different eyes. different spectrums. And I guess my question is on dark matter, is there something outside of something visible light that we just don't have the technology yet to see what the presence is? And then the second thing is in a different sort of caveat to that is what if it is there, but it's actually in a different dimension.

So until we have that technology to see something in that dimension, we can then see that it's right in front of our eyes. And actually might be here on Earth as well, not just in the sky. So I guess sort of a... It's sticking outside the box. Yeah, I mean, is there a radiation that we don't know about yet? It's giving off something, is his first part of his question, that we don't know how to detect you.

That's a great question. I think five years ago, there would be a real great answer. We could say, you know, here's one thing that we haven't detected yet, but we actually have just detected it, and the answer is gravitational waves. So this, and this was a recent Nobel Prize in physics. And one part of the dark matter community is really excited about the use of gravitational wave astronomy to probe properties of dark matter in the early universe. And the idea here is that what dark matter did in the distant past could have left an imprint on gravitational waves.

And unlike visible light, gravitational waves, let us probe really far early into the history of the universe in a way that we never could before. So this was actually a very prescient question that this is exactly the future they're in right now. So there is another question that I've got, and that's what if we're in the realm that dark matter does not interact with regular matter, that there is maybe this dark realm, but dark matter only interacts with gravity and not with any of the other forces or some new force? So this is sometimes called the nightmare scenario. I think Jody, Jody would agree with that. That would be very frustrating for those experiments. What do you mean in a nightmare scenario? So our best way of understanding what dark matter is

is to grab it into the lab somehow. So Jody's experiments are based on this principle of dark matter hitting a nucleus of ordinary matter. At the large Hadron Collider, we try colliding two protons, two ordinary matter particles and look for signatures of maybe some. some dark matter being produced. If dark matter does not interact at all with ordinary matter except for through gravity,

then we wouldn't expect any signatures from these experiments. And what we would end up doing for the next decade is learning more and more about how weekly dark matter must interact. And how could you test that out? The upside to this is that there is already some indication that there may be a way to to probe this. And this is called small-scale structure. So what we do know is that dark matter forms the gravitational seed of every galaxy that we see in the sky.

And we can track something about the dark matter density by following the orbits of the different stars in those galaxies. And one thing is coming out is that, well, we know that there is dark matter there, because we can see the velocities of the stars don't make sense unless you have additional mass. to have additional mass. But if we look more carefully, and now we have more and more data on this, the stars still don't quite seem to be orbiting at the right velocities for the simplest dark matter models, where dark matter just kind of sits there in a bubble.

And one possibility is, if dark matter, for example, interacted with itself, the density of dark matter would be different in each of these galaxies. And you would see slight variations that we may may not be seeing in the data currently. This is Science Friday from WNYC Studios. And so why is this called, what did you say, the nightmare? I want to hear how Jody feels about this one, too, is an experimentalist.

Why is this the nightmare scenario, flip? So this nightmare scenario would mean that our best ways of looking for dark matter, our favorite ways. And, you know, Jody's experiment is the one that I really hope actually will discover what dark matter is. but in the nightmare scenario, it would be invisible to those experiments. So it's, wow. So, yes, go ahead.

I think what it means, though, really is. Go ahead, Jody. Sorry, I didn't mean to cut you off. No, that's what I do for a living. I'm sorry. I think it just means that we have to change our approach completely to trying to study dark matter. It really means that we're not going to be able to study it in a laboratory on Earth. The only way that we're going to learn anything more about dark matter is to start looking at the cosmos as a laboratory, and that becomes very, very, very difficult.

I had a couple things that I'm excited about there, which I know that there is because when it comes to gravity, you know, different amounts of, it makes time change. So you can actually, in some of these papers I've read, detect dark matter with really, really sensitive clocks, which is, I haven't seen anything done with it. But it's just one thing that I saw recently that I was really excited about. But the other one is I also know that there is, I mean, aren't there a slew of new results from space that really do seem to show dark matter? I mean, you have the 21. There's a radio signal from the ancient universe. It seems to have been affected by dark matter. And there's a couple things now.

Did I see something this week about the center of our own. galaxy, there's giant black holes, and there's something in the way of some weird stuff in there that's affected the dark matter? I think I wrote about that, but I guess my question, though, is like, there are some things that are very specifically like people are now like dark matters there, right? Wow. So there's in China, and there's another one in Australia. So, Jody, you're saying that we're really going to be having to depend on what we can detect

about gravity and everything from the cosmos instead of capturing something in our own little laboratories? Well, I hope not. But right now, you're right, there are a lot of, there are anomalies. The hard part about, I mean, so now we're, I mean, some of the things that you're alluding to, kind of pulling apart,

many, many different things that Ryan has alluded to. So there are some experiments out there that are looking at using atomic clocks to try to detect dark matter. So one idea, and Flip, I'm not sure how familiar you are with this, but there is this idea that maybe dark matter might be these cosmological defects in space. And using atomic clocks to try to detect these topological defects. And I think the idea is, if I remember correctly, is that when the clocks go through the atomic clocks,

they're very, very sensitive, so they can sort of measure very, very tiny changes in time. And so when they go through the topological defects, they would measure, you know, very, very tiny time shifts. And I think, so there are people who do atomic physics who propose these different types of experiments with atomic clocks. All right. So that's what the first thing.

I have to leave it there because we're right out of time. That's the thing that I've been waiting for. for the entire hour, though. He just wants to hear that dark matters actually does warps of gravity fly through space. We love talking about it. We run out of time with Jody Cooley flipped today to enroll. You can't end the story. It'll never end.

It's a never-ending story. I mean, we got to find it one day. We will. We will come back to this. Thank you all for taking time to be with us today. One last thing before we go, we want to give a heads up to Chicago because join us Saturday, a week from tomorrow, June 16th, special night of science and music at the Harris Theater. Mathematician Eugeneia Chang is going to tickle the ivories on the

We'll search for urban coyotes with WBEZ's Curious City. We're bringing you a radio play about space rocks falling from the sky performed by Second City. Second City's comics are going to be there. Don't miss it. That's Saturday, June 16th, tickets are going fast at ScienceFriday.com slash Chicago. Next, a week from Saturday, June 16th, ScienceFriday.com slash Chicago. Hope to see you all there. We've run out of time on an hour gone by quickly when we talk about dark.

matter. We'll be you. We'll see you next week. I'm Ira Flato in New York. Hey there, listeners. You know Cy Fri's favorite ocean creatures are cephalopods, right? And Cephalomanio will soon be sweeping the nation as we launched Cephalopod Week. We've teamed up with Atlas Obscura for a series of Cephalopod movie nights in San Francisco, L.A., Seattle, Denver, Chicago, D.C., and New York. We'll have Cephalopod scientists there, too. You don't want to miss this one. So go to ScienceFriday.com slash movie nights for tickets and info. That's ScienceFriday.com slash movie night.