Daniel and Jorge Explain the UniverseDaniel is joined by guest Dr. Crystal Dilworth to discuss the cosmic microwave background.
Learn more about your ad-choices at https://www.iheartpodcastnetwork.com
See omnystudio.com/listener for privacy information.
If you love iPhone, you'll love Apple Card. It's the credit card designed for iPhone. It gives you unlimited daily cash back that can earn four point four zero percent annual percentage yield. When you open a high Yield savings account through Apple Card, apply for Applecard in the wallet app subject to credit approval. Savings is available to Apple Card owners subject to eligibility. Apple Card and Savings by Goldman Sachs Bank USA, Salt Lake City Branch Member FDIC terms and more at applecard dot com. When you pop a piece of cheese into your mouth, you're probably not thinking about the environmental impact. But the people in the dairy industry are. That's why they're working hard every day to find new ways to reduce waste, conserve natural resources, and drive down greenhouse gas emissions. How is US Dairy tackling greenhouse gases? Many farms use anaerobic digesters to turn the methane from manure into renewable energy that can power farms, towns, and electric cars. Visit us Dairy dot COM's Last Sustainability to learn more.
Here's a little secret. Most smartphone deals aren't that exciting. To be honest, they're barely worth mentioning. But then there's AT and T and their best deals. Those are quite exciting.
They're the kind of deals that are really worth talking about, like their deal in the new Samsung Galaxy Z flip six. With this deal, you can trade in your eligible smartphone, any year, any condition for a new Samsung Galaxy Z flip six.
It's so good, in fact, it will have you shouting from the rooftops.
So get yourself down a street level and learn how to snag the new Samsung Galaxy Z flip six on AT and T and maybe grab a ladder on the way home. AT and T connecting changes everything requires trade in a Galaxy s Note or Z series smartphone limited time offer two hundred and fifty six gigabytes for zero dollars. Additional fees, terms and restrictions apply. See att dot com, slash Samsung, or visit an AT and T store for details.
Hey Crystal, did you know that the secrets of the universe are all around us?
What?
Like?
Where?
No?
I mean, answers to some of the deepest questions in science are literally.
All around us, like hiding under my bed or what.
Do you mean?
Yeah, they're under your bed? But they're also just right here in the air between me and you.
Really guess Bob Dylan was right.
What do you mean, Bob Dylan.
They're all just blowing in the wind.
I guess Bob Dylan was a poet and also secretly a physicist.
And a philosopher, Which aren't we all doctor's a philosophy anyway.
That's right. That doesn't mean we know anything about it, but we have the title.
Hi.
I'm Daniel. I'm a particle physicist and co host of the podcast Daniel and Hoorgey Explain the Universe, brought to you by iHeartRadio. My co host, the hilarious and good looking Orge cham is not here today to join us with his amazing jokes about bananas.
He does love a good banana.
He does love a good banana. But instead, today we have a wonderful, amazing co host, Crystal Dilworth. Crystal introduced yourself.
Hello, I'm doctor Crystal Dilworth. I'm a neuroscientist. My PhDs in molecular neuroscience, so the molecular basis of nicotine dependence from Caltech. So I'm just a curious person that loves science communication and I'm super excited to be here to talk to you today.
All right, well, thanks for joining us. So you studied nicotine addiction. Does that make you in the pocket for big tobacco?
It's a classic dilemma, right, do you accept research funding from big tobacco? I was supported by NIH. I escaped that quandary, so.
You stayed clean. In my field, it's always a question of do you take money for weapons research?
Yikes?
You know, like my parents, for example, worked at National Labs work on weapons programs and helped develop essentially weapons of mass destruction, whereas I try to stay away from that and work on things that will never affect anybody's life. So maybe there's a parallel there. But Crystal, you are a PhD scientist, but you're also not just a scientist, right, You're a dancer, You're a movie star.
You're I guess I should have led with that. So I became part of the PhD comics universe through the PhD movie. So I played Tagel in the PhD movie and the PhD movie too, and that's how I sort of came into Jage's orbit, and we've been working together on and off.
Ever that lights to audition for a movie. I mean, you ever acted before?
I had acted in children's theater. So nothing on camera, nothing serious that was going to be seen on every continent on the planet. And it was really hard for me because I had started grad school thinking I was going to give up my life in the performing arts. No more dance, no more theater, no stages for me. I was going to be the best scientist anyone had ever seen. I was going to eat, sleep, breathe science, do the right thing, be a good person. But I had been reading PhD comics since I was working in the lab. And when you get an email saying PhD Comics is coming to your campus and they want to make a movie, a live action movie or live action YouTube series about this comic that has been your you know, your inspiration for grad school? Do you want to be a partition.
It's like therapy for people, right, And I traveled with Whoorgete. People will come up to them and say, if it hadn't been for your comic, I would never have made it through grad school.
Right Yeah, I mean, if it hadn't been for the comic, I never would have gone to grad school. So that's that's a whole other conversation. It made me.
For your grad school.
Yes, I hold him very much to blame. I don't know if he knows that, Jorge, it's your fault, but yeah, it was just the carrot was too big.
So I was.
I was at a Biophysics Society meeting, which is about three hours away from Pasadena at the time that Jorge was running auditions for the PhD movie, and I went to my last session, got in the car, drove from San Diego up to Pasadena audition for the movie, and then drove back so I could be there for my eight am poster session the next morning. Like my advisor like as if I was never gone, he would never know. Yeah, And that was sort of the beginning of the end for me because through working with Jorge, I discovered that science communication was an area that I could work in after grad school, and that's what I do now. I host a show for a Voice of America that highlights science and technology that's happening here in the United States and it's broadcast internationally. I was recently selected as one of the Triple as IF Then Ambassadors. I'm a role model for women in STEM. Thank you, and I'm really excited about what that means, and I, you know, I love doing these types of things. I'm happy to sit down here with you.
And do you feel like people these days still have to sort of choose between having a career in science or having a career in sort of the creative sector, art, dance, you know, public speaking, or do you think there's more opening now for people to bridge that gap and live two lives and not have to hide from their advisor that they're doing this other thing.
I think that the Ivory Tower is still pretty restrictive in terms of what it will accept for its tenure track faculty, But I think that if you haven't chosen that as your path to walk, there's a lot more leniency. You asked about careers. I think it's difficult to make a full living in the arts and a full living in science. So in that respect, maybe you would have to choose one or the other. But there's so many exciting spaces for collaboration. I don't feel that anyone should feel that they have to give one of those up in order to do the other.
Well. I'm really excited about the idea that science could be more open to more kinds of people. Not just people who look different or come from different places, but people whose interests are broader, and that we don't have to be only people who are super zero focused on exactly this one kind of science and they have other interests and they do other things in their life. I think that's probably going to be good for science and also good for science communication if we have people from science who know how to do this thing. In my lab, specifically, I encourage the students to do science communication, send them to conferences this kind of thing. I don't know if that's good for their careers or not, but I figured, since I try to do science communication, I should try to not prevent my students from also doing it. I don't know if that's a good idea or not, but on this open minded process I'm experimenting on my students, but also on this podcast, we want people to understand that everybody can understand science. One of the goals of this podcast is to zoom around the universe and take crazy, amazing things and make them actually understandable, not just jargon said while waving your hands, which isn't helpful on podcasts, but people can go away and feel like I get it. I know what that is. I understand relativity now, and we want to make break down those barriers and make people feel like they can figure it out too.
Oh I'm all for that, all right, So let's.
Get into it today. We're going to talk about something really amazing, as we alluded to earlier, something that's all around us, a secret of the universe, deep dark knowledge about how things in the universe work, the ancient history of the universe that has just been sort of floating around in the air around us with nobody noticing for I guess thousands of years.
Literally like a color you can't see.
Yes, exactly, if only our eyes could open it. I talk a lot in this podcast about opening new eyes. I feel like science is always figuring out new ways to look at the universe, and every time we do so, we realize the universe. Wow, it looks so different in using these other eyes than the ones we're familiar with. So yeah, it's like a color that we can see. And also it's one of my favorite stories because it was discovered kind of by accident. You know, folks who were trying to do one thing, developed this technology accidentally stumbled into this incredible wealth of knowledge. About the universe.
I think that there's a lot of really cool stories, especially in astro about accidental major discoveries. That seems to be one of the really big fields of science where that that's possible.
I feel like I'm so jealous sometimes of astronomy, because every time they look out into the universe with a new device, they find something that doesn't make any sense. We talked about recently the podcast these Fermi bubbles. It's like huge structure, the size of the galaxy, the nobody ever seen before, found ten years ago. But whereas in particle physics it feels sometimes a little bit more difficult to find new things. It's rarer that we like find a new particle nobody hadn't expected. So sometimes I'm jealous of astronomers because they get they get to see things they don't understand more often, and that's like the launching point for a discovery, right when the universe gives you a clue and says here's something you didn't ex then you get to unravel it.
I feel like for chemistry and neuroscience, which are my area, is like the analogous story is like the discovery of LSD, like some chemist was like, what's this? I'm going to eat it?
And then I was like, whoa, Well that's the big leap forward in neuroscience discovery of LSD. So what were they trying to do when they discovered LSD?
I don't actually remember. It's like such an irrelevant part of the discovery story that I can't, off the top of my head even remember what they were trying to synthesize.
All right, well, today we're talking about something unseen but then discovered something surprisingly revealed that told us deep knowledge about the universe. So let's not tease it anymore. Today we're going to be answering the question what is the cosmic microwave background? So this is something which is invisible and caris a huge amount of information all around us, and it was discovered by accident about fifty years years ago. It's a pretty funny story. Actually, some folks were building a radio telescope to do something else. They want to do radar and communication, and so they built this device and then they heard this buzz on the device. Is this noise? And at first they were like, oh, this is annoying and we can't get rid of it. They thought it was like a malfunction of their telescope. They couldn't understand where it came from.
So microwaves. Can we just start there? I have one.
I so you're an expert in microwave backgrounds because you can use a microwave.
I can use a microwave. I'm an expert microwaiver. I'm not sure how to extrapolate my knowledge of heating up soup to the beginning of the universe. Can you help me draw that connection?
Yes, for once our podcast will actually have practical knowledge in it, folks. Yes, we'll draw that connection. But first I was wondering what everybody knew about microwaves, Like, do people understand microwave background radiation? Does that make sense to them? Is this something ever already familiar with or is it something nobody had ever heard of before? And so, as usual, I walked around campus here at you see Irvine, and I'm eternally grateful to the students here for being open to being asked these random questions by a scruffy looking physicist. So before you hear their answers, think to yourself, do you know what the cosmic microwave background is? How could you explain it to a random dude who accosted you on the street. Here's what, folks that you see. Irvine had to say.
Something that's ongoing in the atmosphere having to do with microwaves.
I don't know, no microwaves that are present everywhere. I do not know.
I've heard the topic.
I've watched a couple of videos, but I don't understand.
Whatsoever wave like, yeah, I don't know it's material or just wave. There is something like that a present the outside of Okay, I don't know. It's a lemnent of doors and all.
Right, So Crystal, what do you think of those answers? You impressed?
I don't think I would say impressed. But there's a question diversity of topics that the answers are connecting to, like electricity or something.
Yes, yeah, well it's like electricity or something. That's a pretty broad answer, so it's pretty close. You could tell that some people had no idea what we're talking about and just sort of guess generally physics. A few people had heard of it. I like the guy said, I watched a couple of videos, but I have no idea what it is that tells me that there's an opening here to really explain the microwave background. You really need this podcast, Yes, exactly, this one is for you, dude.
But like the I like this answer remnant of the Big Bang. I mean, we're really getting to something there, aren't we.
Yes, absolutely, somebody definitely knew what we were talking about. So let's get back to your question and break it down.
I know how to heat up soup in a microwave. I even know that microwaves are long radio waves. I think of them as really big waves. I mean, I'm a I did a lot of fluorescence microscopy, okay in a lab, so I like nanometers is a scale that I'm used to dealing with, and microwaves I think of being so big as to be ineligible. So help me out here.
Yeah, I love this sense of scales in science right for me. For example, anything bigger their proton is like way too big and complicated even think about, right, Whereas mechanical engineers never think about the individual molecules. So microwaves is really really just a relative term. Remember, microwaves are electromagnetic radiation, just like light. So everything that's coming into your eyeballs is electromagnetic radiation. But it's part of a much larger spectrum. The visible light is just this one little slice that we happen to be able to see because our eyes react to it. But down the lower frequency, the longer wavelengths, you have radio waves, and at the higher end you have gamma rays and X rays. It's all just part of the same big electromagnetic family. And microwaves are a kind of radio waves, as you said, and they're called micro because they're short for radio waves. Radio waves can have wavelengths like meters long.
Just all about scale.
It's all about scale, and so compared to that, microwaves, which have wavelength like a millimeter, are really small, but of course you know, they're huge compared to visible light or gamma rays or anything that I know anything about, frankly. So microwaves are megawaves for me and microwaves for most people. So cosmic microwave background. The connection is the wavelength of the electromagnetic radiation. And we talked on this podcast recently about how microwaves work, and they work in the same way they pump this same kind of radiation into your soup to make it hot.
Using it to add energy to the system.
That's right, And then fueling you so that you can think about the universe and reveal all of its secrets.
I'll work on that, all of the secrets revealed.
Yeah, exactly. Jorge usually has a banana before every podcast because apparently he can't think without a ban Is that's something you know about him.
For I know that he definitely does not operate without a banana. I do not operate without a coffee. So as long as he's got bananas and I've got coffee, we're usually good to go.
That's all that's required around here. Well, this is a perfect spot to take a break. We'll be right back. With big wireless providers, what you see is never what you get. Somewhere between the store and your first month's bill, the price, your thoughts you were paying magically skyrockets. With Mintmobile, You'll never have to worry about gotcha's ever again. When mint Mobile says fifteen dollars a month for a three month plan, they really mean it. I've used Mintmobile and the call quality is always so crisp and so clear. I can recommend it to you, So say bye bye to your overpriced wireless plans, jaw dropping monthly bills and unexpected overages. You can use your own phone with any mint Mobile plan and bring your phone number along with your existing contacts. So dit your overpriced wireless with Mint Mobiles deal and get three months a premium wireless service for fifteen bucks a month. To get this new customer offer and your new three month premium wireless plan for just fifteen bucks a month, go to mintmobile dot com slash universe. That's mintmobile dot com slash universe. Cut your wireless bill to fifteen bucks a month. At mintmobile dot com slash universe, forty five dollars up front required equivalent to fifteen dollars per month new customers on first three month plan only. Speeds slower about forty gigabytes on unlimited plan. Additional taxi, s, fees, and restrictions apply. Seement Mobile for details.
AI might be the most important new computer technology ever. It's storming every industry and literally billions of dollars are being invested, so buckle up. The problem is that AI needs a lot of speed and processing power, So how do you compete without cost spiraling out of control. It's time to upgrade to the next generation of the cloud, Oracle Cloud Infrastructure or OCI OCI is a single platform for your infrastructure, database, application development, and AI needs. OCI has fourty eight times the bandwidth of other clouds, offers one consistent price instead of variable regional pricing, and of course nobody does data better than Oracle. So now you can train your AI models at twice the speed and less than half the cost of other clouds. If you want to do more and spend less, like Uber eight by eight and Data Bricks Mosaic. Take a free test drive of OC at Oracle dot com slash Strategic. That's Oracle dot com slash Strategic Oracle dot com slash Strategic.
If you love iPhone, you'll love Apple Card. It's the credit card designed for iPhone. It gives you unlimited daily cash back that can earn four point four zero percent annual percentage yield. When you open a high Yield savings account through Applecard. Apply for Applecard in the wallet app, subject to credit approval. Savings is available to Applecard owners subject to eligibility. Apple Card and Savings by Goldman Sachs Bank USA Salt Lake City Branch Member FDIC terms and more at applecard dot com. Yeah, so, cosmic microwave background radiation the microwave radiation. Part just refers to the length of the waves of the electromagnetic radiation.
So where are the waves coming from?
Yeah, they're coming from everywhere, Like if you look out into the sky, see this radiation coming from everywhere. And that was the weird thing about their discovery when they turned on this radio telescope for the first time, they heard this buzz and they heard it from every direction. There's sort of two answer parts to that answer. One is where do we see them? Right, And it's coming from every direction, so we see it from everywhere in the sky. And often if you see a map of the cosmic microaid background radiation, it's this weird ellipse with these little dots on it, And that's an attempt to describe what you see in each direction in the sky. So, because the sky is a circle, the earth is a sphere, it's hard to map a sphere onto a flat piece of paper. The best way to describe what you see is if you could print it on the inside of a sphere, so you could look at it and say, oh, in this direction, we see this, In that direction, we see this. The same way. It's hard to make a map of the stars you see in the sky. Right. The best way to do that is like a planetarium. You can print them on the inside of a curved surface, so you can show what we're seeing. So what we see when we talk about the cosmic microaid background is we see this buzz, this electromaic gradation from every direction at once.
So just filling the space that is the universe.
Yeah, it's coming from every direction and hitting us, and it's everywhere. Like if we were here or around Jupiter, or the center of the galaxy or in between galaxies, we would see it everywhere.
So it's originating from the universe. It's just an energy that now exists and bounces around and comes from everywhere.
Yeah, it comes from everywhere. That's the confusing part, I think to a lot of people because people think, Okay, it's light, so it's traveling at light speed and it's getting here. How can it be getting here? Where did it come from? Right? And that's pretty confusing if you imagine that. If you think about the beginning of the universe as a point and from that point things flew outwards and people try to imagine, well, then if it's getting here now, it's coming from that point how can we be seeing it from two directions? And the reason that's confusing is that I think that's the wrong way to think about the start of the universe.
Oh my gosh, how should I be thinking about the start of the universe?
Oh no, well you start with the bowl soup, right, sure.
No.
The way I think about the start of the universe is that it started off infinite, that it's the moment of creation, is not a single point in space, but that the Big Bang happened everywhere, all at once. There was sort of multiple starts from every direction, And what we're seeing now is leftover bits from really far away in that one direction and really far away in the other direction. So if I'm looking at the cosmic microwave background radiation, I'm seeing light that came from the very beginning of the universe. It took almost fourteen billion years to get here from somewhere really far away in one direction. And I turn around and I look in the other direction, I'm seeing light come from the other direction, which came really far away from the other direction, from somewhere else, really really far away. So these two pieces of light haven't talked to each other ever, are they meeting for the first time in the history of the universe here on Earth. So they're not coming from the same place. It's not like we're looking at a little object. We're looking at a huge universe at its beginning. Every direction you look at, you're looking at a different part of the early universe.
So does that mean that the different particles, the different waves of light that our meeting here for the very first time can tell us different things about the beginning of the universe.
Yes, absolutely, they tell us what was going on. It's one spot of the universe over there, and what was going on at one spot of the universe over there. Just the same way when we look at the night sky. Now you look at one star, it's telling you that light is telling you what happened a long time ago in that direction. You turn another way, and light from another star is telling you what happened in a totally different part of the universe, also a long time ago. Those two photons are also meeting for the first time.
So I have a lot of questions about how that information is carried and decoded. But first I'd like to ask when this background radiation was discovered, what did we think it was how did we know that it could teach us and tell us things.
Yeah, that's a really fun part of the story because the guys who discovered this, they weren't looking for it, but there was another team people who were looking for it. They got scooped. So there was a team around the corner. This telescope they built was in New Jersey and it just happened to be around the corner from Princeton, and there was a team at Princeton who was looking for this radiation. They were like scrambling to build a device they could see it, and they got scooped by these guys who were like building something to do something else. The reason they were looking for it is that there was this idea that we could find evidence for the Big Bang. And this is back in the sixties when the Big Bang was still like kind of a crazy idea, not necessarily totally accepted.
Definitely not a television show, yeah.
Not yet, a hilarious television show that propagates stereotypes about scientists. But the idea was that if the universe had started smaller or more dense, right, the universe had started from a really dense mass and then exploded, then Originally it was sort of hotter and denser. And the reason people thought that this radiation might exist is that they'd looked back into the history of the universe. They said, Okay, the universe now is bunch of stars and galaxies, but if there had been a big bang, then the universe we sort of rewind the history of the universe. Everything pulls together and gets hotter and denser, and eventually it gets so hot and dense that it becomes a plasma. And a plasma is really interesting because light can't just pass through it. It's opaque. So there's this moment in the history of the universe. They thought when the universe went from opaque like light couldn't go through it, to transparent. Suddenly the universe cooled and became crystal clear, so that you could, like photons could fly through the universe without necessarily getting absorbed. And so this is this last moment when the universe was a hot plasma and then it cooled, and the light from that moment, they figured should still be around.
That's crazy, I know.
It's like you know your baby picture that your parents took, you know, whatever, years ago, the light from that picture is still out in space somewhere like that's literally true.
I was thinking like gestational periods of the universe, which is like a really weird mental trip that I just went on. I'm back now, Okay, welcome.
But you know, the same way that everything that happened on Earth a long time ago, the light from that is out there in space, the way like TV shows that we broadcast are out there in space flying away. Everything that happened in the early universe is still out there in space. So if the early universe used to be hot and dense and then all of a sudden became cool, then this light could fly through the universe untouched and it should still be out there. And that's what they were looking for. They were looking for this last light from the hot plasma of the early universe, which should then still just be flying around and we should be able to find it. And you know microwave background. Remember that's just another kind of electromagnetic radiations. When we're talking about light, we really just mean electromagnetic radiation.
So finding this radiation meant that we were on the right track in terms of the origins of the universe model.
Yeah, it was really the first experimental evidence that said, Wow, this crazy idea that the universe used to be hot and dense and then expanded really fast might be true. It's you know, this rhythm and science where we say, Okay, got a crazy idea that sort of explains the way things work. Make a prediction, prove it, predict something that we could find that we could only see if your idea is correct. And this is was the prediction. And coincidentally, Jim Peebles, one of the guys who predicted it, just won the Nobel Prize for that prediction this very week. The competing idea at the time was the sort of steady state universe. Universe had been like this, been like this forever. You know, maybe it was expanding, but there's some sort of new source of stuff in it, and that people wanted to believe that. I don't really understand why people wanted to believe.
Biblical origins, don't you think.
Well, see, but biblical origins tell you the universe had a beginning, right. The steady state idea is sort of like the eternal universe. The universe has been like this forever, and for some reason, I think that seemed more natural to people. It seems more natural to me that the universe had a beginning. I guess to some people, thinking that the universe had an origin brought up other questions like what happened before that? And I'm not afraid of questions. I love those questions, But to me, it'd be weird at the universe it existed forever.
I was actually trapped at the Caltech Faculty Club while a visiting professor and one of our staff scientists had an argument over what came before the Big Bang, and none of the graduate students were willing to interrupt the argument to say, like, can we order because we're really hungry, And the waiter kept coming to take our order, and the graduate students kept making eyes at them like we're we we can't. They're still arguing. Eventually, I think somebody came and was like, sirs, can we move this process along? But I guess this is still a hotly contested idea, at least in the Caltech Faculty Club at lunchtime.
Yeah, and you know, sometimes those arguments can feel like they last forever. But at the time there was these two camps. It was the steady State University. University existed sort of in this similar state forever, and the other idea that it came from this hot, dense initial point. And this was the prediction that they made that if the universe had been hotter and denser, it would have be this plasma and it would admit this radiation and we could still find it. You know, it's like you if they had been a rave in your an apartment last night, and you know, you expect like lots of loud music, and the moment that music turns off, that music is still flying out there somewhere. So this is like saying, let's go find that music. It's evidence that there was a rave in my apartment last night, But of course that music is flying off away from us. You would have to like travel the speed of sound to catch it. This is light that we're finding here, So I think it can be a little confusing to digest, like why are we seeing that light here? And seeing it from multiple directions.
So when it was detected or discovered, the scientists knew what they had, and they also knew that there was some going to be some really upset people at Princeton.
They didn't know what they had, like the guys who found it, Penzius and Wilson. They just thought it was noise. They just heard this hiss in their telescope and it was an obstacle to them. They thought, we can't get rid of this. What is going on? And they're like, this is really strange. And then they went around the corner to the physicist of Princeton and they're like, we found this weird thing. What do you know about it? And I think the physicist must have been like, oh my god, we've been trying to find this and you scooped us slash. Wow, wonderful. We learned this amazing thing about the universe. That must have been a really sort of you know, plus and minus moment for them.
So they published it separately. There was no post talk collaboration.
No, they wrote two papers. The guys who actually found it published their discovery, like here's what we found, and then immediately afterwards the Princeton guys wrote a paper saying here's what this means and here's why it's important. But the Penzias and Wilson, they're the ones who got the Nobel Prize because they're the ones who found it.
Man, science, sometimes it's luck.
Yes, I know, and you can be like days or weeks away from a discovery that wins the Nobel Prize. If those folks at Princeton, if their grad students had worked a little harder, or they hadn't taken uch long to order lunch.
Wow, that said like a true professor.
I know when I was an undergrad, a professor of mine who is teaching sing thermodynamics. He was one of the folks racing to discover the Bose Einstein condensate, this weird state of matter, and there were other groups. Was one MIT and one at NIST, and he was able to create the bo Einstein condensate and published it, but he was two weeks too late and he was left out of the Nobel Prize, so it was shared between NIST and MIT. And he was two weeks away from the winning the Nobel Prize. And I always thought, wow, that must be tragic, and he must, you know, wonder like should I have given my grad students two weeks off for Christmas? Or we could all be sharing the Nobel Prize right now?
Right, I feel like we should probably move on, because I could, I could take this topic my soapbox wig really wants to be you know, right now. But it's true, right, like these these things can be so so far yet so close, and.
You never know. You never know if you're around the corner from discovering something amazing, and also if somebody else is one week ahead of you, or if you're sort of on your own and you're about to discover this incredible thing.
That's why it keeps it for it depressed grad students showing up in the lab every day, right, is the hope that the next day is going to be different. It's also the definition of insanity.
That's right, that's right, slash or research.
So when the Princeton group published sorry to like bring us back, When the Princeton group published their paper saying this is what the discovery means, what did it mean?
Yeah, it meant that there was this evidence that the universe had once been hot and dense, and since the universe is not hot and dense right now, it's like huge and empty and cold. That means that the period of the universe we're living in is not the way things have always been, and it means that the history is quite different, and we found relics of the history. This is like fossils of the universe. It's like a discovering Wow, there there used to be these huge, crazy animals that walked along the Earth. Used to be totally different from what we're experiencing now. Now this is on the universe scale. Now we learned, Wow, the universe used to be this hot, dense, nasty, wet plasma where nothing could propagate through and then it cooled. And so that was really very conveying evidence that the Big Bang was a real thing. The Big Bang like happened. It's not just an idea. It's not just a story. It's not just something you read about in a book. It was reality. It was it was these physical events took place. And to me, that's amazing. You know that there's there's this history of the universe and we can uncover it, that there's enough clues out there that we can actually figure out what the objective truth is of the universe, which has sort of been like a big question in human existence, right where do we come from? How's this whole thing been created? We're unraveling that. We're like using science to figure out what the true history of the universe is. That's incredible power.
So when you're talking about objective truth, is this things that can be described using mathematics.
Yeah, we have models that describe the early universe, and those models made predictions, and those predictions are born out to be true. And you know, we can never really claim objective truth. We don't really know what's out there. You can just be trapped in a brain, in a vat somewhere, you know, if the universe exists. But assuming that the things that we're experiencing are real and that physics can describe them, we're making incredible progress in revealing the way we think the earlier universe happened. And I think that's pretty incredible.
So as a physicist, you know that there is a knowable truth that is always true, at least within the universe that you yourself are experiencing.
Yeah, that's one of the things I like about physics. I mean, I love doing creative stuff also, But the thing I like about physics is that the universe answers questions and it's you know, yes or no. It's not like, well, you know, you wrote this this novel and it's pretty good, but in somebody else says no, it's wonderful. Somebody else says no, it's trash. Right, the universe you can ask a question, say a right, which theory is correct? And he ever says this one and that one. You love it. It's beautiful, but it's wrong. There's an objectivity there. It's not just people's opinion. You know. The universe tells you this is the way things happen. But only if you can find those clues, only if you can figure out a way to sort of corner the universe and make it reveal this truth. You don't just get to stand at a mountaintop and say, tell me the answers. You have to figure out a way to find these clues and unearth it like a detective.
And that's a slow process.
Right.
If you think about early interpretation of physical fossils like you know, dinosaurs, et cetera, or you know small sea creatures. We use that to fuel stories of monsters, and it evolved the way that we were describing our universe or our world, but not necessarily to bring it completely in line with the scientific understanding we have now. So how long did that process take discovering this fossil of microwave background?
Yeah, well, I think the idea of the Big Bang dates to the earlier part of the last century, the whole idea that the universe was bigger than a galaxy is only than are only one hundred years old. And then so discovering these other galaxies, finding that they're moving away from us, and then trying to understand, well, if the universe, if galaxies are moving away from us, right, then how can we have at all a sort of steady state model. I think before that people imagine galaxy is just sort of hanging in space. So then discover things are moving away from us, that sort of immediately implies some sort of expansion. And then that brought up these questions like, well, how can you have expansion if the universe is bajillions of years old? And Einstein didn't like that at all either. That's really the origin of that idea. And so then to find this evidence is really conclusive. And then they discovered on top of all that this evidence that this is really from the Big Bang. There's a huge amount of detailed information in this buzz, in this light from the first plasma that gives us clues about what was happening in the Big Bang, the way like you can look at your baby picture and be like, oh, I can tell you know I'm drinking coffee as a two year old or whatever, or he has got a little banana his baby picture. You can look back at this baby picture of the universe and understand why our universe looks the way it does and gives us a huge amount of information about our universe today. Well, this is a perfect spot to take a break. We'll be right back. When you pop a piece of cheese into your mouth or enjoy a rich spoonful of Greek yogurt, you're probably not thinking about the environmental impact of each and every bite, but the people in the dairy industry are. US dairy has set themselves some ambitious sustainability goals, including being greenhouse gas neutral by twenty to fifty. That's why they're working hard every day to find new ways to reduce waste, conserve natural resources, and drive down greenhouse gas emissions. Take water, for example, most dairy farms reuse water up to four times. The same water cools the milk, cleans equipment, washes the barn, and irrigates the crops. How is US dairy tackling greenhouse gases? Many farms use anaerobic digestors that turn the methane from maneuver into renewable energy that can power farms, towns, and electric cars. So the next time you grab a slice of pizza or lick an ice cream cone, know that dairy farmers and processors around the country are using the latest practices and innovations to provide the nutrient dense dairy products we love with less of an impact. Visit usdairy dot com sustainability to learn more.
There are children, friends, and families walking, riding on paths and roads every day. Remember they're real people with loved ones who need them to get home safely. Protect our cyclists and pedestrians because they're people too. Go safely California from the California Office of Traffic Safety and Caltrans.
In the rhythm of our daily lives, it's the little things that make the greatest impact. At the Monterey Bay Aquarium, those moments blossom into memories where every side and sound connects us with the natural world. Embark on a journey of discovery today, from the captivating canopy of the Kelpforest to the enigmatic depths of the deep sea, Monterey Bay Aquarium inspiring conservation of the ocean. Visit Monterey Bay Aquarium Dot org slash together.
So how is that information coded.
It's coded in the little differences. So if you look at the cosmic microwave background radiation maps, and if you're in front of a computer, you should google cosmic microwave background and you'll see this image. It's sort of like reds and blues and greens. And what you're seeing there is that is the slightly different energies you see if you look in different directions. So you get this radio wave it's microwave, and that has a certain frequency, and that frequency means a certain energy, and there's very small variations. And so what we do is we measure the energy in different directions and we see that in some places it's like one hundred thousands hotter or one one hundred thousands colder, and that's telling us something about the density of that plasma four hundred thousand years after the Big Bank, almost fourteen billion years ago, telling us oh, this was a hot spot, this is a cold spot. And those are very small variations in sort of the temperature of the universe at that time. And you might think, well that why does that matter? Who cares about the tiny, little bit hotter, tiny a little bit colder. Well, those are the structures, the seeds of the structure of the universe itself. The universe had been totally smooth, like exactly homogenous everywhere, and there's no way to sort of build anything because every particle is being pulled in every direction simultaneously. What you need to start the seed structure to get like galaxies and planets and stars and people and bananas and hamsters, is you need a little bit of variation. And so these are the original seeds of variation that caused the structure that we see today.
So if everything was all the same, it'd be really boring what.
I'm here, Yeah, we wouldn't be here because you would never form any structure. You would never form really hot, dense things like stars to give light and planets for people to live on. It would just be smooth and not very dense. So in order to get anything interesting in the universe, you need the little packets of density to start off with.
And if those packets were even slightly different, our universe would be so completely different we wouldn't even recognize it.
Yeah, you wouldn't have a galaxy here. You might have a galaxy somewhere else, totally far away. Yeah, And the amazing thing is that these those variations are totally random. They come from quantum mechanics. Like where do you get these variations from the beginning? If the universe started out a sort of symmetric and how else could it start, then how do you get any variation to see the structure comes from quantum mechanics.
Quantum randomness strikes again. It keeps following me around.
It's everywhere. So you get little random fluctuations. Those little fluctuations get expanded into bigger fluctuations, and then they become, you know, larger and larger. So we said, see these really really minor, very subtle fluctuations in this early plasma. You know that took fourteen billion years for gravity to build on and to make something big and beautiful and elaborate that we are living in today.
So for scientists start studying the cosmic microwave back on the CMB right now, are they asking questions about the past or are they looking at either at present time or future time?
Yeah? Wow, that's a great question. I think people want to understand the past because they want to know the future. Like I'd like to know how long is the universe going to be around Is it going to keep tearing itself apart or turn around and crunch? And part of answering the questions about the future means looking into the past and understanding the origins and revealing the mechanisms. So I think we're asking mostly asking questions about the past, but really because we want to know the answers about the future. And the CMB reveals all sorts of things like how much dark energy was there, how much dark matter was there in the very early universe, how much matter was there in general, All sorts of things are encoded in the details of the CMB, And that's the kind of thing that scientists are focusing on today's is pulling out as much information as possible from this early map of the universe.
So this is just one of the many types of radiation that I can't see. That's being like that I'm basically swimming through as I go about my day.
Yeah, imagine if we were all blind, humanity was all blind and nobody could see, it'd be difficult to imagine, Oh, there's all this information around us that we're not capturing. The light would be there, but we just wouldn't be using it to understand our world. Well, that is our situation. We are all blind. We're blind to all these different other kinds of light and particle that are all around us with incredible information about the universe that we just can't see until we build telescopes and new devices that are sensitive to these kinds of radiation and these particles that can help us understand these clues.
What's the most mind blowing thing about the CMB that you ever learned? And can you describe that moment?
Yeah. The thing that I think is amazing about the CMB is that we can see sound in the CMB, Like.
Okay, wait, we can see sound.
Yeah, we can see sound. So what is sound? Sound is waves. Sound is like ripples. So for example, you sit in your bathtub and you move your arm, you see waves in the water, right, So those are waves. Sound is just waves and air. So when we say well, maybe instead of saying sound, I should have said we see ripples. We see waves in the CMB. We see oscillations because there's some kind of matter in the early universe, in that early plasma that can interact it like pulls itself together like normal matter, and some matter that doesn't like dark matter doesn't really feel anything, And so those different kinds of matter have different kinds of oscillations, like one one is pulling in one way, the other one is pushing the other way because it interacts. And we can see patterns in the cosmic microwave background radiation that reflect the oscillations of the plasma, and those oscillations are sensitive to like how much matter was there that was interacting, how much matter was there that was not interacting, And that tells us how much dark matter there was a bajillion years ago. And to me, like revealing that crazy, complicated, subtle fact about the early universe from looking at like the wiggles in this tiny little bit of light that nobody even knew about until fifty years ago. It blew my mind. I thought, like, wow, people are really digging details out of this thing.
Do you remember where you were or what you were doing when you had that thought?
Oh that was earlier this morning when I googled cosmic microwave background.
No.
I came to astrophysics and cosmology sort of late because my background was more in particle physics and understanding you know, the basic building structure, basic building blocks, but I was always interested in the universe, and so I did a little bit of self teaching. After I got tenure, did a little bit more reading and try to understand this stuff. So it's about ten years ago I think that I really started to try to wrap my mind around what is this stuff out there in the universe? What is a What are we learning about the origins of the universe from the light that we can see here on Earth.
So you mentioned the CMB being able to give us clues about dark matter behavior. Is that sort of one of the new areas of research for the CMB, or you know, what are the hot topics? Now? If there's a gold Russian data for you know, CMB related research, what question should I be putting on my grant application?
Yeah, that's great. I think the most important question that the CMB can answer is sort of like the pie chart of the universe. What is most of the energy of the universe used for? And we know roughly the answer. It's five percent matter, twenty seven percent dark matter. A huge chunk of it is dark energy. And the cool thing is that we know that from looking at matter and looking at stars and looking at galaxy and seeing the expansion of the universe. But the CNB gives us a totally independent way to measure those fractions because again sort of the oscillations of the plasma are sensitive to those fractions. So what people are doing now is trying to just get more precise measurements and asking does that agree with what we already think. And the way you get more precise measurements you just get more data because you're looking for really small variations. So we have these successive generations. First the telescope in sixty four that just heard like, oh, it's there. Then there was a satellite called Kobe in the nineties that found these variations that were like ooh, look this interesting information. Then there was w MAP, which is a satellite saw even more details, and then recently the Plank experiment. And so if you look at the CMB over years, it's sort of like this blob that's becoming more and more and sharper and sharper focus and answering these questions in more detail. And recently we're sort of getting slightly different answers, like the CMB tells us this is this much dark energy in the universe, whereas other measurements tell us a slightly different answer. We don't know why those things don't agree. Is it because our model the universe is wrong? Or because one of these measurements is wrong? And so that's sort of the current puzzle. It's like, how, well, let's make these two kinds of measurements as precise as possible and see if they agree, and that they don't. Ooh, that's a fun clue because it tells us we're going to learn something.
So how do I interact with the cosmic microwave background every day? Or do I Is there any way for me to see it? Or is it a way for it to influence my life that I just might not be aware of.
Well, because they are microwaves, they hit your body and they heat you up very slightly. Right, It's not a huge amount of radiation, but you can see it if you have one of those old television screens that a cathoid ray tube, not like a flat panel display. Those things are sensitive to the microwave background, and part of the fuzz on those screens comes from this background radiation. Really, and the snow on those screens comes from this microwave background radiation. So you could literally see this evidence years and years and years ago.
So I don't need a radio telescope. I just need an old TV and I can see it.
That's right, you can see the secrets of the early universe.
That's a really great TV show. Amazing.
Yeah. And I think another thing that people are often confused by sort of again this like where was it? And I think the things to remember is that it was everywhere. And so the CMB they were seeing in one direction was hot plasma that was in one place, and the stuff we're seeing another direction was hot plasma we're seeing from somewhere else.
So I know in academia there's often multiple schools of thought about really important things, theories, hypotheses, et cetera. And it sounds like the detection of these radio waves this microwave background helped to resolve one of those disagreements. Has it caused others? Do people not believe in it? Or are there heated debates happening in the hallowed halls of the Ivory Tower about the CMB.
I think it's a sort of a process, like a lot of the old questions been put to rest. I don't think anybody seriously disagrees with the Big Bang theory anymore. But of course there are new questions, and some of those new questions are about, like what do we see in the CMB. There are some weird things we don't understand, and those lead to like crazy ideas. For example, there's one spot in the CMB that's colder than all the other spots. It's called the cold spot. What a great name. And it's also kind of big, and you can say, well, you know, there's random fluctuations. You would expect, some cold and some hot, but this one is colder than you would expect and bigger than you expect. So it's it's kind of unusual. And anytime you see something a little out of the ordinary, you wonder, is that a clue or is that, you know, just random. And so people speculated things like maybe that cold spot is evidence that our UNI, when it was really young, bumped into another universe and left basically a bruise. I know, that's hard to imagine, it's hard to even think about. But some people have this theory that there are multiple universes created once, sort of in a multiverse theory, and if those universes were near enough each other, they could have interacted very early on and they predict exactly this kind of signature in the CMB as evidence for that. Now is that a prediction or is this sort of a post addiction, Like Okay, I saw this weird thing and now I'm going to try to explain it and I get to make this crazy theory. I don't know, but that's the kind of thing people argue about.
So still TBD, why should watch this space?
That's right, there's a lot left to learn about the universe from the cosmic microwave background.
How should I be thinking about this? Like when I'm having my you know, shower thoughts are so important, I think. You know, when you're idly at rest doing a mundane task that your brain doesn't have to think about, it wanders off and usually for me into like existential question.
That's where you think about physics.
Physics, yeah, more more philosophy, you know, those big questions like why why are we here? Is this seven am call I'm getting ready for? Really that important in the grand scheme of things, like on a universal timescale? You know, does anything matter? Should I just be watching a Netflix marathon all day to day? These types of things. So as I'm having those thoughts, deep thoughts, With deep thoughts, How should I be thinking about the cosmic microwave background? Is it a fossil, as you said before, because that sounds very static, but it's something that's continuing to move and continuing to give information. Is it a comforting wrap of radiation from the early universe that's giving me a hug? How should I? How should I think about this?
I think you should think about it aspirationally. I should wonder what else is out there? What other information is floating out there in space. It's going to give us some addible, deep knowledge about the universe. It's going to change the entire context of our lives. And we don't even know it exists yet, and then in one hundred years or fifty years or two years, somebody will discover it reveal something deep about the universe, and we will have not even known. I like to look at the history of physics that way and be like people stumble across something and it changes the way we think about the universe. And I hope that there are so I said aspirationally, because I hope there are more of these. I hope there are more moments when we dig up something from the early universe and it teaches us something and maybe it's surprising, and people are trying to do that. Right now, the plasma from the early universe ended about four hundred thousand years after the Big Bang, and this is the only light we can see because before that, all the light was just reabsorbed by the plasma, so it's sort of gone. But people are trying to dig deeper. They're saying, well, what about like neutrinos from inside of that plasma, because they don't interact very much, and maybe we could see them. We're gravitational waves from the very first moment. So we're trying to open up new kinds of eyes to see deeper and deeper into the history of the universe and answer our questions about that. So yeah, think about that. Think about what your children or their children will know about the universe that we can't even imagine.
So I'm like, I'm just imagining the situation in which the people that ask questions and want to know things are kind of like this nerve center, and we have so many different senses like you and I would have sight and sound, but we have all of these different detectors that scientists have developed as part of their senses. And so what I'm hearing you say is that we're going to continue to develop more senses as we want to be able to detect the information around us.
Is that accurate science is making esp real. We are developing new senses to experience the universe.
You heard it here. First, guys, the universe was in a state in which this type of radiation wasn't able to escape, and then there was a cooling event in which the universe became transparent, allowing light to emanate through it. And this radiation is part of that early expansion, and it's coming from all of these different directions because we're expanding our idea of the Big Bang beyond the point theory, and so it's radiating from everywhere. Because we are the center of the universe obviously we're humans. It's meeting here on Earth right where we are standing in the world and able to give us information about the past experiences that it had in helping us understand the universe.
That's right. But aliens somewhere else they're also seeing a CMB. They see a slightly different map because the light that's getting to them left from a different place, but the same way they see different stars in the sky than we do. They're seeing a slightly different CMB.
So everyone would see everyone, all of the different extraterrestrials in our universe is seeing a different one and studying it differently. And maybe one day we'll be able to put our data together and I get the most accurate picture of it started all.
Of this, That's right. So I hope we do one day get to talk to alien physicists. I have a lot of questions for them about how the universe works and how they think about it, and whether we're studying objective truth or just based on our human bias and our senses. I think they probably have all sorts of other ways to observe the universe we can't even imagine. But I hope that they're impressed with what we've accomplished and that we can learn from them.
So the universe began, and had it begun slightly differently, we wouldn't be here. But it developed the way that it did, and so we're able to ask questions about how it all started.
That's right. So the amazing thing about the cosmic microwave background revadation is that it's all around us and it gives us clues about the very beginning of the universe, and hopefully one day we'll find more clues and learn even more about the origins of our very existence.
And it's heating me the way that I heat soup. That's my gutsling made my big takeout for this.
That's right. It's exciting you. It's exciting you the way your microwave excites your soup. I hope this podcast is excited our listeners.
I hope so too.
So thanks Christal very much for joining me today.
Oh thank you for having me. This was a great conversation.
And for those of you out there, if you still have questions about this topic, send them to us to questions at Daniel and jorgey dot com. We really do answer all of our emails, and thanks for tuning in. If you still have a question after listening to all these explanations, please drop us a line. We'd love to hear from you. You can find us at Facebook, Twitter, and Instagram at Daniel and Jorge That's one word, or email us at Feedback at Danielandhorge dot com. Thanks for listening, and remember that Daniel and Jorge explain the universe is a production of iHeartRadio. For more podcasts from iHeartRadio, visit the iHeartRadio app, Apple Podcasts, or wherever you listen to your favorite shows. When you pop a piece of cheese into your mouth, you're probably not thinking about the environmental impact. But the people in the dairy industry are. That's why they're working hard every day to find new ways to reduce waste, conserve natural resources, and drive down greenhouse gas emissions. House US dairy tackling greenhouse gases. Many farms use anaerobic digestors to turn the methane from manure into renewable energy that can power farms, towns, and electric cars. Visit you as dairy dot COM's Last Sustainability to learn more.
There are children, friends, and families walking, riding on pass and roads every day. Remember they're real people with loved ones who need them to get home safely. Protect our cyclists and pedestrians because they're people too, Go safely. California From the California Office of Traffic Safety and Caltrans.
We're Paint Care and we're all about keeping it simple. We make recycling leftover paint easy with convenient locations like your local paint store. We have three simple rules for painting smarter and reducing waste. One buy only what you need, two use up what you already have, and three recycle the rest. Visit paintcare dot org slash three simple rules to learn more or find a paint drop off site near you
