StarTalk Podcast: Cosmic Queries – Origins of the Universe with Janna Levin

[Music] this is star talk neil degrasse tyson here your personal astrophysicist with my co-host chuck knight chuck and baby what's happening neil all right jack chuck you know what today is it's it's a rare thing we got to do this because i think people will want us to do it this is this entire episode is a shameless plug for the very latest star talk book nice that is just coming out and it and the the reason why it's a maybe it's maybe it's not shameless maybe it's full of shame the point is it's the title of the book is cosmic queries the book was inspired by this spin-off of the star talk flagship and so i just want to celebrate that with all of our fan base and with you and so i just thought i'd just put that out there chuck i love it well first of all uh shameless shameful for me it makes no difference no more it's the same place all the same so so there's that and it's published by national geographic books who published the first star talk book that's right uh you know what the first star talk book was called um let me hold on for a second the start talk book yeah i'm looking at it over here wait a minute it was called star talk the star talk book yeah this one inspired by this uh this spin-off branch of the star talk universe right and so and so it's questions 10 chapters and each chapter is a really deep question that we barely have time to address given the nature of what we normally do in a cosmic queries so what for this episode we're going to do we're going to focus on chapters three four and five oh wow those are how did the universe get to be this way how old is the universe oh that's so impolite and and what's the universe made of close let's see so we we have to we have to reach uptown for our sort of cosmologist in the house john 11 jamnet welcome back to star talk and you're published on these topics you got your own books right so first there's together chuck the black blues [Laughter] so so you've got that that book and a more recent one called the survivor black hole survivors guide which is a very pocket-sized book and everything you needed to know to visit and not die in a black hole i think is that that did they characterize that properly so how do we get to be this way what does it mean to have forces and matter and energy and space yeah universe why you gotta be like this why you gotta be like why didn't it be like this universe i thought we were cool you know i thought we should i have a star talk book idea for you though what's that a book a self-help book for like universes on how to be better like how to be a cooler how to be able to be a badass universe more actualized universe well actually this is for the for the multiverse in us all right yeah the more acts as an astrophysicist i can say we've got stars galaxies and planets but you look at it as a physicist at a much more sort of refined level and i see things that gather according to forces so what was what's been going on to give us the universe we see today well it's really interesting you mentioned stars galaxies and planets and oh my those and those and those are things sugar's allowed one really bad joke i'm a good audience i laugh at all history okay that's very good all chokes that's why you're my favorite guest and uh happy birthday jen i didn't properly introduce you you're a professor of astronomy and physics up at barnard college that's why i said we go up the street because you're just you know two miles north of the american museum of natural history and uh you've been doing this since childhood and it's just been great to have your enthusiasm and plus you you you hosted a pbs special but on black holes what was the title of that black hole apocalypse see see what i'm saying yeah it's nice you were the on-camera host of that novel one of my son's favorite that's so sweet it is i held a little black hole in my hand i got to do all kinds of cool cgi yeah yeah that's crazy but okay go on so well so so you all the stuff that you listed stars galaxies planets are are luminous objects meaning they reflect or emit light and that actually makes up much less of the universe as you well know um than we used to believe it's actually less than five percent of what's out there i mean if you think about everything anybody has ever seen or ever will see makes up less than five percent of the universe the universe is in its volume has dark energy permeating every part of space and yet it is it is really should be called invisible because it's not dark looking it's it's literally invisible we see right through it and there's dark matter and those um right so people will think oh dark matter why isn't that just black holes but so there's a difference between matter you can't see because it's not giving you light and matter that you can never see because it will never give you light or something yeah how would you distinguish that yeah no no it's a it's a really good point i mean a black hole is really just a shadow it just casts a shadow and uh you have to illuminate behind it around it to notice the shadow just like a tree doesn't make a shadow in the darkest night um so you need you need some light source to cast a shadow so that a black hole is just absorbing that light that's deep i hadn't thought about that so yeah you only know a tree shadow is there because there's light yeah surrounding the shadow the shadow is the absence of the light yeah the presence of the tree is the absence of the light the tree is absorbing some of the light and and if that's not that shadow falls in the forest well the thing you know and only the shadow knows how's that you got me are we good there okay so that's what people don't appreciate about black holes that stepping into the event horizon of the black hole is just like stepping into the shadow of a tree there's really nothing dramatic about it um you're just you're just going into that region where you the light is being absorbed but it's a little trickier because the light can fall in behind you but having said that dark matter which is what we were originally talking about doesn't interact with the light at all there's no shadow cast there's no darkness it just passes right through so there's a cloud of dark matter presumably between me and my computer maybe not very much from the local universe it affects gravity right so so it interacts gravitationally so there's a lot of it and there's a big halo of it around our galaxy so when we look at our galaxy we think it's this kind of planar spiral and it's so beautiful and it's illuminated by all the stars but really there's this halo around it of dark matter and we look right through the dark matter and that halo affects the behavior of the galaxy the evolution of the galaxy and and actually dominates the mass of the galaxy so it's just we're invisible to the dark matter too you have to realize it doesn't see us either dark matter technically if it had eyes would look right to us too wow so this is a sci-fi story the dark matter people coexisting with regular matter people would just walk through each other that's exactly what i've been talking i could be in the same body right as a dark matter alien and we wouldn't because my gravitational field is so tiny um won't interact at all because that uses forces that dark matter doesn't respect there's a movie about that it's so there is there's a movie waiting to happen in there yeah man man okay so all right so we got dark matter dark just 95 percent of everything and so so is it possible no is it possible we're the anomaly if 95 of everything is the if 95 of everything is the thing is it possible that we are the anomaly that we're at the thing right we're not we're not the thing it depends on how you look at it the confusing thing about dark matter we know examples of dark matter we know neutrinos neutrinos exist they emanate for instance from the sun from thermonuclear reactions they don't interact with light at all they are technically invisible so we know examples of dark matter but we know that the neutrinos that we know about can't be the dark matter in the universe we just can tell it's not heavy enough it doesn't have all the right properties so there's something like a neutrino so you're saying a neutrino is an example of a physical object that doesn't really interact with us but only weekly only very weakly so this could be matter if it's matter at all that interacts even less with less strength than a neutrino would that's right now the chuck's question is like really interesting because it could just be the fact that there's so little of us i mean there should be none of us because you asked why does the universe got to be this way and it it doesn't we don't really know why there's a little bit excess for instance of matter than antimatter and so it doesn't have to be this way we're trying to figure out why it is this way if if there was equal amounts of matter and antimatter when the universe was created there'd be none of us because we would just merge with our anti-matter and annihilate and there'd be nothing left but so some law of physics that we take as as canon was broken or violated in the early universe yeah and we still don't matter always comes in matter anti-matter pairs and we won that contest right as this excess froth right uh and so so you just declare that some rule got broken in the early universe that sounds very like you don't know what's going on well that's true we don't know what's going on there you go so this is actually interesting let's go have a beer we're done here we do know that there are slight matter anti-matter violations in the laws of physics why there are these tiny violations we don't know um and there's an example so so so if you made the universe with equal the universe was created with a lot more matter in it a lot more and a lot more antimatter it all just went away and this little ashy residue was left of this little excess of matter right so so that that's what goes into us so could you have a universe where in fact the matter and antimatter were strictly equal all the way down and still have a functioning universe maybe not with stuff in it but is that would it be its own space its own place could you have a universe where it's like uh where that has just dark matter and dark energy in it and no regular matter you absolutely could have a universe i mean if you imagine the multiverse which you made very quick reference to in the beginning you know like if you keep kind of making universes like babies they're all slightly different right they have a certain uh genetic code we know it's still the underlying laws of physics but maybe certain slight parameters can be seeded differently and so maybe there's a universe that has no excess of matter over antimatter and that really depends on whether or not it's absolutely fundamental to the laws of physics or it's something that got broken like you said you know for instance universe is left right symmetric i don't expect it to be different on my left and my right right because that doesn't even really matter i can move around the universe should be the same but i know that in this room it's not i know that my microphone's on my left and that's different that's broken it just physically even though the laws of physics should be the same on my left and right i love the looks on your faces right now for anyone who is just listening i just got like four eyes yeah it's like what the hell first of all you had me at baby universes because my mind just started going off to all these other universes that were just like you better take care of your kids that's too many kids you got too many kids there could be a whole bunch of little baby universes out there some of which are are you could say less successful on the basis of what we think is important which is the emergence of sentient life right and you know you're not going to make a lot of sentient life out of dark matter presumably now there could also be this thing where the dark matter sector has its whole reality it ha it makes stars and galaxies we just can't see them and it sees them and it has this whole other reality and we're just like in parallel completely invisible to each other dark galaxies dark stars dark planets all right so so from what i've read and i have a cursory understanding of this i have like an evening news account of this at different times from the early universe to today matter gravity dark matter dark energy all have different ways or different strengths of their capacity to manifest okay so so who's dominating today so today we know that the overall energy density of the universe is dominated by dark energy and exactly as you said that was not true very very far in the past it it's like it's like a soup of ingredients that compete at different phases and the dark energy the strange thing about dark energy is as the universe expands because the dark energy is everywhere it's like it feels more of it so the expansion gets a little faster and then it feels even more of it embracial everywhere it doesn't it doesn't dilute right like if i if i took a hot gas and i expanded it it would dilute and get weaker dark energy and that's what happens to the the primordial soup of matter in the early universe it's really powerful so we're diluting our gravity we're diluting our gravity and not diluting the dark energy yeah so that's right the expansion is is we're getting further and further away from other galaxies so that's diluting their gravitational effect on us right but okay so you compare the two the dark energy systematically wins out eventually it'll win even if in the beginning the gal you know that's not necessarily the galaxy but like the stuff dominated and then the universe was expanding and it got more and more dilute and weaker and weaker and then the dark energy there it was and it just took over so dark energy feeds off the vacuum of an expanding universe well this is it might be the energy of the vacuum of the expanding universe so the more vacuum you get the more energy from the vacuum you know weirdly that reminds me of the weeping angels episode of doctor who where weeping angels they feed off of your life energy and you disappear out of your time and you show up in the past because they took your present life energy from you so dark energy is is taking whatever we possibly had left of ourselves it's a cosmic vampire there's a vampire that's what it's doing well if it keeps going like this you know a friend of mine um used to say we have to do astronomy now because eventually eventually in the very far future there will be no galaxies in view anymore they'll all be too far away from there'll be no cosmology there'll be no cosmology we know cosmology we'll just see our galaxy and the rest of the sky will be empty imagine astronomy under those circumstances we'd never know that there was anything outside of our ground well that's what it was until 1920. until 1920 no one had any idea that the fuzzy objects were galaxies it was just the solar system and the stars in the night sky and that was the universe in fact that was the universe to einstein there was no understanding of a big bang or anything else and so that's right it was just no in fact when did who's the guy who first advanced the big bang the the monk or the the priest the belgian priest right who really put the math behind einstein's equations did he by then have hubble's expanding universe he must have i think um so friedman uh uh and la mesha and some of these uh you know robertson walker there were a bunch of cosmologists that were thinking about this long before actually hubble and einstein thought they were wrong so einstein publishes his theory but he doesn't he doesn't know that there's a big bang it's not like it just hits you in the face you gotta you gotta study the mechanics of the theory and so people jumped in even before he did and they realized oh this is really strange if you imagine a universe dominated by matter they didn't even know about dark matter but just stuff it actually wants to expand it's actually heart that universe doesn't want to just stay static it's actually really really hard to make it static so i guess what i'm thinking is they're imagining an expanding universe before they even know anything about galaxies they're just thinking about stars in the night sky they were just imagining yeah they were just imagining like a hot stuff everywhere you know just pretend right so without galaxies we have no knowledge of an origin of the universe and we'd be dumb stupid yeah so yeah we have to do astronomy now because one day we're going back to that same state yes but only because it those galaxies won't be observable at all right at all but so it'd be somebody would be like son believe it or not there was a time where people looked up a time and they thought that they saw things son oh grandpa chuck tell me more when you were a child believe it or not son they used to look up there and see things but no longer basically most the evidence that we had a big bang in our past we'll eventually um just fade away so so janet before we take a break and then get to our actual cosmic queries with people's questions uh what i lose sleep at night wondering whether we today live in a time where an entire chapter of data has been removed from our awareness just as it will be in the day when there are no galaxies in a post-apocalyptic civilization they will know nothing of chuck's stories about the day gone by and they will try to figure out the universe with what they've got so what what chapters are we missing today thinking we have full access to all the data yet we don't and that's funny because i lose sleep because i normally drink vodka before bedtime okay we should yeah we should have little shots for our like if you get if you get the cosmic query wrong [Laughter] so you know so jenna you don't worry about whether we're missing something i totally do but i think this is a really interesting question because people say things like if there's no way to observe the multiverse then it's not a scientific question i think that's false for instance in the far future if people say there's no way to observe other galaxies and i don't know why and one person pontificates maybe it's because the universe was expanding so rapidly that they're now beyond our view they'd be right but it's technically untestable for them right so i i do think it's a scientific question even if you can't resolve it observationally so yeah there are things like if the universe has extra spatial dimensions and and right now they're really small and we're really big maybe that's something we can't test right now but maybe in the far far past it was technically testable wait so chuck she's saying one day a new dimension is going to grow out the side of your body since the pandemic that has already happened mercifully we're all like filmed from here [Laughter] chuck out six legs we gotta take a quick break when we come back janna you're here for us uh we're gonna take questions from our patreon members on these very deep segments when star talk returns we're back star trek cosm aquarius this is a celebration of the release of the second star talk book called cosmic queries inspired by this spin-off of our show one of one of our more popular formats of the star talk portfolio and chuck i got you here for this of course that's right and we're doing uh chapters three four and five and i got their titles right now how did the universe get to be this way how old is the universe and what's the universe made of and chuck you've been collecting questions let me just lead off janet i've heard people say the universe is designed just for us okay just so that we can have life but that seems really inefficient if life as we care about it human life has been around only for a couple hundred thousand years and the universe has been around for 14 billion that just seems really inefficient so so if you want to say you know everything's set up for us that's a pretty big waste of time and space yeah especially if we're just here to make plastics for a little while and then we're going to go on and leave the plastic behind you know the plastic will survive us it's like a george carlin skit he's like the planet just wanted us to make plastic for it and then be gone right because there's no known thing that dissolves plastic right yeah not yet so chuck give me some questions dude all right here we go let's uh ball from patreon give it to me everybody's from patreon and this is richie uh damani richie damani says firstly janna neil chuck thanks for taking the question so we know about the lhc at cern uh which has made huge discoveries in particle physics but do you have any knowledge of a larger project that it is in consideration that will further our knowledge of the quantum world yeah janna is there another particle that people think is out there and now we need something bigger than the large hazard on the collider to find it well dark matter so so the large hydrogen collider has been very successful it's very exciting it discovered the higgs particle which explains why anything has mass what did you say hicks particle or higgs boson pigs i thought you said the hickory part was a little different the his particle explains why you eat possums very culturally insensitive yes exactly just the hits particle is just like i believe i'm uh on a quantum level y'all constantly barbecue that possibly all right well so you know it it's called the god particle in like sort of colloquially but it's it was originally called the goddamn particle by leon letterman um the nobel prize winner he wanted to write a call his book the goddamn particle because i hadn't found it yet and his publisher made him change it to the god particle which he said ended up alienating two groups those that believed in god and those that didn't so it's since stuck it's stuck yeah um so but the lhc could have detected dark matter and that would have been really like that would have just been what everybody had mostly hoped for and it hasn't so could we go higher energy and higher energy if you think of the energy of the large hadron collider it's from a very early era in the universe's history and you'd expect to be able to make kind of everything the earlier back you go the more you can make more kinds of vocals i never thought of it that way you're telling me the lhc is a kitchen it's a cosmic kitchen and so if you whatever energy you hit you just look on your cosmic scale and say i got you back to three seconds in the big bang and then higher energy got you back to one and a half seconds so where what how much how much more energy you're going to need to get to the formation of dark matter in the early universe like 10 million times higher oh okay chuck that's all right yeah we got that you got this not a problem right and so that's really 1.22 gigawatts of energy that's what we need like 1.21 gigawatts and we're going back in time too so yeah so in the recipe book that neil's looking at that tells you if i cook at this temperature i'm going to have this number of particles that's just based on as much as we understand and as much as we understand between the energy of the large hydrogen collider and the very very you know the earlier second of the big micro tiniest little fraction of the second the big bang is like 10 million higher in energy but it doesn't mean we're right i said there could be like a bunch of stuff that starts to appear that we had no idea about that and that's what everybody's other stuff like not just like dark matter might appear in there you know and other stuff might maybe dark matter isn't alone maybe there's like a whole dark sector a whole dark reality and we start to discover tons of dark matter particles and forces dark forces so jenna i love this you're saying a more powerful collider could just open up a whole new door to what's going on in the in the universe cooking with particles now we do know that we can't we will never hit certain scales with the usual technology like you would have to have all the resources in the solar system and a particle collider the size of the solar system so that's why we do need 1.21 gigawatts of power established just just think of just i don't not to beat that to death but just think of doc brown hearing marty tell him in 1955 oh yeah it runs on 1.21 gigawatts of power and doc brown freaks out and he says you're from the future i'm sure plutonium is just available at your local drug corner store but in 1955 we can't have one point twenty one so do we have to wait the the forty years or whatever so are we on our arc to get there i think that's the benefit of astronomy is that stuff happens at higher energy scales than human beings can engineer and so we we know we have high energy particles hitting our atmosphere from supernova explosions or solar systems that are um are at higher energies than the hedgeon collider and so the universe is a better hadron collider than our large hadron collider that's right it just requires you know it's harder you can't manipulate it right you just have to wait what you want you got to wait until the particles find you right exactly the part will bite you in the ass okay i guess you exist it's it's basically like being a an actor don't call us we'll call you exactly just gotta wait for it to roll up all right so all right so so that's good i i like that and so but i want to emphasize a point you made before we go to the next question what you're saying is in our life experience if something lasts three minutes or five seconds or one second that's not very much time and who cares about the difference but in the early universe they're things that lasted a trillionth of a second and then a a quadrillionth of a second and we say oh that's just less than a second but each of those are huge differences in the energetics of the early universe is that a fair way to think about it absolutely i mean there's stuff that can be created in the first you know trillions of trillions of trillions of seconds that very quickly decay away into other stuff and will never be made again because the energy scale required to create a single particle with that mass even though the mass itself is objectively not a lot compared to you know a coffee cup it's a lot for one particle um and it will never be made again probably in the history of the universe wow so anything that was born in the first trillionth of a trillionth of a second and dies a trillionth of a second later lived for a trillion of its own lifetimes yeah okay i mean that was a full life right man that's that was it's life expectancy wow look at that yeah okay so we do think like you can make in fact it's possible that one of the heaviest single particles that ever could be made is a microscopic black hole and that it was made not by dead stars not by collapsing matter but it was made as like a quantum particle in the very early universe and that it was the weight of like a little pile of flour but it was incredibly smaller than a nucleus right so it's very dense to be a black hole it's black hole down exactly it's very spatially tiny but heavy for its incredibly small spatial size and if i lost my keys into a microscopic black hole yeah don't don't reach in to pull them out because that ain't gonna work i'll get you another pair of keys another set of keys for what you're doing it's like chapter three and black hole survival so you know this reminds me of janna i i forgot which book forgive me but the the novelist kurt vonnegut yeah one of his novels uh he says this is the last sentence ever spoken by humankind it was one scientist speaking to the other and says let's try it the other way that's the end of all civilization so it's like let's see if we can make a mini black hole last word ever spoken well so there was some discussion serious discussion about whether or not the large hadron collider could make one of these and a mini black hole a mini black hole and we usually think no you really couldn't until you were at the much much much higher energy but it does turn out that the universe does have extra spatial dimensions and they're of a certain size you could actually manipulate the strength of gravity if you think about it gravity dilutes when you have more dimensions like more volume it gets more dilute so if these dimensions you start to notice it brings the scale of making black holes down in energy because gravity is getting uh it's it's it's getting into your range because of these extra dimensions so what you're saying is if you have extra dimensions then the gravity has more space to dilute into yeah right but that means that your thresholds of gravity bad stuff is lower is lower so you might make a black hole at the large hadron collider if that's the case and so there were injunctions taken out by people to try to stop the large hadron collider from turning on because there was this anxiety well if you're going to make a black hole it's going to like digest you know it's going to consume the earth it'll kill us all um but the argument which might not be very soothing because it is theoretical is that they would evaporate too quickly they would just go off like firecrackers so you're saying you would possibly make them and they would consume the earth except that hawking radiation protects us that's right and we look black holes are not as dangerous as people portray there's a black hole in the center of our galaxy we orbit that black hole it dominates the entire behavior of the galaxy and uh it doesn't it's not a vacuum cleaner says the person who wrote the book black hole survival guy right no one's no one writes a book um if you want to survive just stay here basically no one writes the book the puppy survival guide no you want survival guides with stuff that's going to eat you okay that's funny this is the kitten survival guy no no black hole survival guy explorer's peril we got to take a quick break when we come back more cosmic queries when star talk returns we're back star talk cosmic queries we are celebrating the release of the second star talk book cosmic queries inspired by this format and we've got with me by the way we're gonna have different guests for the different kinds of chapters that are in the book and right now we've got some very deep questions about what's the universe made of and how did the universe get to be this way jan 11 always good to have you you're a good friend of the show and thank you and by the way that place behind you this looks like a bunker but it's but it looks like a like a chill place to never be found so where are you right now so i am uh also director of sciences at a cultural center in brooklyn called pioneer works which is largely originated in the arts and um and i've been doing science events here and bringing science into the community it's very much that is just so brooklyn cool i had to say this is the what i love about this place it's free and it's open to all and it's a donation only model and we we really bring like amazing people here to talk about science to talk about art to have exhibitions and it's really important to us that the doors are open for everybody and the intersection between science and art is much greater than anyone ever thinks about or imagines and you're there in the middle of that so keep keep up the good work all right so chuck give me some questions for our cosmologist in the house toby sonnenberg says hey dr tyson and dr levin sometimes physicists say that the existence of a particle such as the axion is predicted by a theory or completes a theory what do they mean by this oh good question well that's okay so let's you know what the best example of that is is the higgs which we already mentioned so we looked at the standard model of all the matter in the universe and there was just like one thing missing because there was there we couldn't make sense of why particles had masses essentially unless the higgs was proposed so that what the higgs does it's basically higgs was a person peter hicks what was the person it's a person okay posed the theory and the idea of the higgs particle was that that there was this field that permeated all of space kind of like what we think about dark energy so some people wondered if dark energy itself was like the higgs permeating all of space but the numbers didn't quite work out but it could be something like that dark energy could be something like this field that permeates all space and as we move through this field because of our interactions with the higgs it creates a kind of inertia we get sticky we get gluey it's like viscous moving through it and that's what gives us mass right mass is means i'm harder to push around than a thimble but i'm less hard to push around than a car there's inertia and this difficulty pushing around has to do with our interaction through the field what's the idea so so the higgs particle was filling a gap so that's different from discovering a particle that nobody ordered that's true so like robbie said it's a great quote the physicist robbie said who ordered that when he began to discover more particles so the higgs was predicted to fill a gap which is exactly what the question was about and lo and behold there it was this can make all you all very proud of yourselves right because it means you you you understand not only the physics that we've discovered but the physics are waiting to be discovered that that's that gives you pretty good confidence there that's the best although i have to say everyone really hoped that something like the large hadron collider would just would discover something we had never predicted but people don't understand about physicists we don't want to wrap it all up in a bow and be done we want more and so it would have been incredibly exciting if they had discovered something that nobody had ordered so you you look forward to being work deep in ignorance yes we look forward to the questions the questions are the fun part in fact robbie who you're quoting his mother used to say to him did you ask a good question today yes i like that so basically you guys are doing something basically you guys are just never satisfied it's what you really see that's right yeah it's a weird job like the more questions you answer you're getting yourself out of work [Laughter] okay you want job security all right here it goes all right all right let's keep it going and let's do a lead in up to a lightning round so let's do a little faster and then we'll pick up the pace and see how how far we can get well that's a perfect segue into john schwelbach's question because john says this hi janna uh please tell me what is string theory in two sentences well he wants it in two sentences there you go okay he's right on time okay go for it string theory is actually so compelling because it can be summarized in two sentences when we look at the microscopic universe we used to think we saw little fundamental particles it's possible that if we zoom in on those fundamental particles all of which are different there's a lot of them quarks and electrons that when we zoom in we realize that they're each tiny loops of string the same kind of string and they're playing different harmonics on the string to express as a different particle so an electron is simply ringing at a different note than a quark but they are fundamentally the same that was more than two sentences but it was good that was good that was good so you're saying everything in the universe could be made up of strings that's right even light photons even the higgs how about dark matter all of it would be the same fundamental string playing different notes wow wow so the string will be playing notes that we can't detect right such as dark matter dark energy that we can't see i say right so we think of particles as just their identity in terms of whether they interact in certain ways and so all of those features it's like a short list of numbers are harmonics on this chain so the universe is nothing more than one big version of name that tune and this is the one we're in we're stuck in this one in this movement all right give me another one good short answer janet that's so funny best short answer ever if somebody else is able to observe us but we can't observe them could you imagine they'd be like god what a shitty song all right so this is woody what he says is a quantum vacuum possible in intergalactic space or anywhere else and would an area of absolute nothing be a hole in space time so if you can actually get to nothing did you punch a hole in space-time well there's a lot of stuff going on there yes there is quantum aspect is the most important to some extent you can never have a quantum completely nothing a vacuum nothing you can't have a complete quantum vacuum and that's because of the heisenberg uncertainty principle says you know i can't ever really precisely state that a particle's there or not there it means i can't say it nothing exists because i have the same uncertainty okay there's an uncertainty there's no listening even existence let me know yeah wait you can't be easy on chuck jenner easy on chuck chuck had a hard night last night exactly you're laying this on him now i drank last night you said let me know damn no oh yeah so you know to say there's nothing means you have zero uncertainty that there's nothing right and you cannot have that at the quantum level it doesn't exist there is no it's not just that there's a problem with the human knowledge there is no meaning to saying it's exactly precisely empty so you're saying that something can't exist is basically what you're saying they're can't be there can't be a nothing they're just because no no no no no it's not that there can't be nothing you cannot be sure that there's nothing well there's nothing isn't quite as empty as you might imagine the most nothing you can get might be so this is why people talk about the dark energy as being the energy of the vacuum the most nothing you might be able to get is this kind of frothy quantum things a cloud of possibilities and that has an energy associated with it and you can calculate the energy associated with it and and so far we keep getting the number wrong if i look at quantum mechanics as i understand it and i calculate the energy of the vacuum i either get zero or i get something absolutely enormous what i don't get is dark energy so you could say dark energy is not mysterious what's mysterious is why it's so low why it's either not zero or huge and that's what the real mystery is is how do we how do we make the energy of the vacuum tuned just to where what we observe and and uh nobody knows how to do that all right i i crow i cry foul here wait so so what you you are taking as a given that everything you're describing is happening in the space time that we've come to know and love but back to the person's question if you did find a place where the quantum laws don't apply have you torn uh have you opened up a rip in the very fabric of space time where possibly other rules of quantum behavior apply well or no rules at all yeah i would say that that uh to do such violence as to have a hole in space-time so you have to think of space-time as being formed responding flexibly to matter and energy and so you can't make a hole without having tremendous other phenomenon going on it just it we know what the solution would be would be nice smooth empty space time so you make a hole by doing something like a black hole like doing some some real intense violence with energy and matter to create that whole so i would say i would say maybe closer answer to uh our listeners question is that it might be quite the other way around that quantum mechanics creates space-time and that is a new idea that's been kind of people been flirting with maybe for decades but that it's not that you have these two separate things gravity space-time quantum it's that things like a black hole emerge from the quantum phenomena and not the other way around so you don't even have space time right unless you have quantum mechanics i get it so you can't even pose the question what happens if there's no exactly you can't separate the existence of space time from the quantum phenomena that operates within it if it's in fact they created it in the first place yeah if that's so one way to think of it is like embroidery so embroidery like let's say you're you're you're embroidering something each thread is like a quantum phenomena and from far away it might look like a black hole but on closer inspection you realize it's a bunch of inter-tangled quantum threads right exactly wow that's cool that's a really cool concept it's pretty cool i'm just saying i can't i can't wait to go to a party with a bunch of theoretical physics and do whatever drugs they are doing [Laughter] we'll sign you up truck exactly fast lightning round let's do it okay here we go my name is pronounced frederick uh if the universe is with everything expands does that mean that quarks grow too or is it just the space between them okay very good question question lightning round go yeah here i am in brooklyn brooklyn is not expanding famous reference to annie hall so locally i'm bound to the earth i'm not expanding with the expansion of the universe because locally the earth is more important to me also my atoms are bound together by different forces and they're stronger than the expansion rate of the universe presently i'm not being torn apart if that's maintained in the future uh remains to be understood it might be that the expansion gets faster and faster and eventually indeed brooklyn begins to expand and um and that's just something we don't know about the fate of the universe and in fact the final chapter of the cosmic queries book takes you there it looks at the great rip the runaway where not only does everything get ripped apart from everything else the very structure of particle matter itself breaks apart it can't even hold itself together that scared me i lost sleep that night it doesn't scare me i've been in that position many times well i just can't hold myself together you can't hold yourself because you can't hold myself together all right chuck we're actually out of time but i want to get one more question in here hey jana hey neil i love you both big fan for a long time and thank you both for instilling me with a cosmic perspective in our universe we observe virtual particles that pop in and out of existence could this phenomenon be compared to that of a 3d object passing through a 2d flatland i love that it's very interesting well it is possible so i said string theory but i only had two sentences which i already overused but it is possible that there aren't just strings but there are membranes higher dimensional surfaces and so imagine yes we started with particles points and then we went to strings one-dimensional objects now maybe there's like a membrane a two-dimensional object and maybe there's higher dimensional objects as high as you can fit and the higher dimensional space-time so one of the ideas is imagine we live on like a three-dimensional membrane and when we see a point particle it's really the end point of a string stuck to our membrane wow it's not exactly the question asked no no but it is it is the intersection of dimension that's so cool though yeah yeah so that i see a point particle moving around in my space time because i can't see that it's really connected by a string to somewhere else and also imagine how that allows for what would appear as an illusion to be faster than light travel right because i could have this thing that's actually connected and it's doing something you know synced up but that's because it's fundamentally connected and that's amazing so it's like to having the point of a pencil down on the paper and the point is what i'm seeing on the paper exactly but then there's a whole a whole pencil connected to that point yeah okay that's some freaky freaky stuff man that's freaky friday so when we calculate the energy of the vacuum and try to find the dark energy we have to calculate all of these kinds of objects that might be in the universe and what they're contributing in their quantum energy to the vacuum wow damn we got to close it there i'm not gonna sleep for three days right now janet thanks for showing us your your digs at pioneer works and and chuck chuck you you tweet at chuck nice comic yes always good to find you there thank you sir for saying it i just love that janna has pioneer works it's like right and jenna we see your pioneer works your uh your your your swan song accomplishment to science and truck tweets to tweet right [Laughter] all right so we just encourage you to check out cosmic as the second star talk book national geographic press i'm neil degrasse tyson you're a personal astrophysicist and of course i bid you to keep you

Channel: StarTalk

Views: 398,013

Keywords: startalk, star talk, startalk radio, neil degrasse tyson, neil tyson, science, space, astrophysics, astronomy, podcast, space podcast, science podcast, astronomy podcast, niel degrasse tyson, physics

Id: _c5gIoh9Gpg

Length: 48min 53sec (2933 seconds)

Published: Thu Mar 11 2021