Perception of Time and Reality

Our listeners love puzzles, paradoxes, and hidden patterns almost as much as we do. On TikTok, those fascinations come to life People are breaking down physics, exploring geology, and explaining why the world works the way it does. You'll see impressive experiments, explanations that finally make sense, and connections you didn't expect. It's like having a lab, a lecture hall, and science museum in your pocket. TikTok is where wonder is shared where curiosity turns into discovery and where millions learn something new every day Ryan Reynolds here from MintMobile, with a message for everyone paying Big wireless way too much. Please, for the love of everything good in this world, stop. With Mint, you can get premium wireless for just fifteen dollars a month. Of course, if you enjoy overpaying, no judgments, but that's weird. Okay, one judgment Anyway, give it a try at mint moobile d. com slash switch. Upront payment of forty five dollars for three month plan equivalent to fifteen dollars per month required, introate for three months only, then full price plan options available. taxes and fees extra, SF terms at MintMobile. com Hey St talals, Neil You're about to listen to an episode spepecially drawn from our archives to serve your cosmic curiosities. Their archives run deep. If you enjoy this Take a peek at the full catalog on your favorite podcast platform There's a lot there to tickle your geek underbelly. Check it out Welcome to Star Talk. Your place in the universe where science and pop culture collide. Star Talk begins right now I'm Neil DeGas Tyson, you're your personal astrophysicist. And I'm Lindseay Nick Walker, senior producer of StartTalk. And Neil and I just co authored a brand new StartTalk book coming out september twelfth. Yeah, this is the third in a series of collaborations with national geographic books. And this one is titled to infinity and be hond And it's available for pre order from the StartTalk website, StartTalkmedia. com slash books. If you do pre order the book, you have a special access to a conversation that I'll be having with Lindsey Walker. She's been my senior producer for years She's behind the scenes in practically every Star Talk episode you've ever seen or heard. I look forward to doing a live stream for our audience and they'd be able to submit questions in advance. We'll see you there. We'll see you then StartTalkmedia. com Sash book. This is Star Tks Neil deeGras Tyson here, you're a personal astrophysicist. I got with me my coodach, Chck nice, Chck. Hey, what's happening? All right. It was good to have you there, man, especially when we have Cosmic queries. Fan favorite. Oh yeah, fan favorite. We love them You get to ask a question with sort of entry level participation in our Patreon program is five dollars a month. That's it. And we collected them. And you know in advance what you're asking about because today's topics involve physics and philosophy. Oh. People love just talk about stuff For which there is no answer. Of course, you know why because it makes them feel like they have a stake and a say. It like that nobody has the answer. Yeah Nobody has the answer. So I'm just as right as you are, right? Like No, you're not You're still an idiot, okay ee, I have a PhD in philosophy and physics. I have what's called an informed opinion. You, on the other hand, went on the internet, saw somebody on Joe Rogan's show say something about something else. and now you think you're an expert. shut up Shout up All right, sorry. Okay, that's the end of our show. Well, we're bringing into this an old friend and colleague. Sewn, Carol, Sean, welcome to Star Talks Hey thans for having me on Dal. Welcome back to Stark talkalk. I should say this is you've been on at least four or five times You are one of the world's experts on not only physics, being a physicist, but You' also that subcategory of physicists who cares about philosophy and have engaged philosophers on the frontier of our understanding of physics So it's great to have you for this Cosmic queries And dare I say, we crafted this cosmic queries around your expertise. So you are the Homewood professor of natural philosophy at the Johns Hopkins University right there in Baltimore And you have a joint appointment at the Santa Fe Institute. Now that institute, everything I know about it, those are deep thinkers. about things that it's like, what T twist your head like a dog hearing a high pitch. Well it And you're the fractal faculty at the Santa Fe Santa Fe Institute. And your expertise in quantum physics Baceime, cosmology, love it, emergence U entropy Dark matter, dark energy, symmetry, origins of the universe U And perhaps most people who know you know you through your mindscape podcast So always good stuff happening there. Those things that make you tilt your head and scrunch up your eyes, like that's my lane. That's what I do. That's you. Okay, so I say this lovingly and crazily, stay in your lane. Okay So tell me what is Natural philosophy, eyegass saw that term You know, seventeenth, eighteenth century Pilosophher natural philosophy was the then term for what today we would call physics because political philosophy and religious natural philosophy was physics. Why isn't that just Physics profess There's a joke in philosophy circles that once an area of philosophy starts making progress, it gets spun off to a completely different field. So it never looks like philosophy actually makes progress You're right, Newton, Galileo, those folks would have called themselves philosophers. The idea of a physist hadn't been invented yet But what happens is Academia loves to categorize and silo people. So they invent a physics department and a philosophy department and they examine what questions you could ask and they decide which is which does is that it means that all the in between stuff because it's really a continuum here, not interstitional ideas and things Those just get lost. And we're at a point in physics right now where questions like you, what is an observer? What is infinity? Why is the past different from the future? What is emergence? Like these are physics questions. What makesly night different from other nights? Sorry Philosophy and Pong. Is that a song lyic? Is that So, so So you are there to clean up the pieces is what you're saying Well, I'm actually there to understand the universe. I think that the common thing within natural philosophy is we're not studying process of science or anything like that. We're studying nature, we're studying reality, but there's a way of doing it that it's kind of foundational that you know takes a step back. Physicists, pless their hearts. You've met physicists, Neil. I know this. and As them about by the way, Chuck Anytime someone prefaces something, by bless them. Bless your heart. You're about to insult them inself Nothing good ever, you know, It's just In the same sentence says, bless their heart. Especially if you're old white lady from the South. You know what I mean? It said, Oh, bless her heart. She's just a little whore. That's all. Sarah, you know That's how it goes Okay. I started the book by saying you do not need a PhD in theoretical physicist in physics to be afraid of quantum mechanics, but it doesn't hurt And physicists don't want to dig into the deep questions about quantum mechanics. They want to calculate their differential equations They shut up and calculate They shut up and calculate and that's the opposite of what I like to do myself. So the philosophers humor me on that. So just just to make sure all our audience is on the same page Quantum mechanics is is amazingly successful predicting and describing reality. But that reality defies all our common sense. And you reach a point where you just say, Okay, I'll just live with that and continue to calculate And Sean, you're telling me, you're not satisfied with that You want to understand Crazy quantum phenomena. on some level where we can sit out and say, okay, now I understand it. Is that what's driving you Yeah, absolutely. just like it drove professors Einstein and Schurdiger back in the day, but there was this consensus that developed in the nineteen twenties and thirties by physicists where like you say We have some equations, we can solve them, we can calculate them, we can make predictions and book beautiful exquisite agreement between the calculations and the predictions, without knowing what's going on without agreeing on what's actually happening in the world. And there's a whole bunch of physicists who will say, oh, no, understanding what is actually happening in the world, that's not my job. I'm just here to make predictions strongly feel that's not right. I'm here to help understand what is going on in the world Right? So you're the show your work part of this whole equation Splain your work. show it. you can't hide anything. No sweep the rug. Yes. It's okay to come up with the answers, but we gotta know how we got there Absolutely. Yeah.. So Sean, what's been in all the buzz recent years is quantum entanglement, all right and Let me offer my best explanation and you correct it? And then but then give me your understanding of it, all right? You can create two particles simultaneously that have sort of complementary properties quantum properties to them and they can separate And they know about each other. There I use the word no They know about each other's existence The moment you make a measurement of one of them Other particles's properties manifest to whoever' observing them. And he manifest instantly transranscending the speed. of light And so we know that happens But Sean, you're going to tell me that you understand it or will you not? Well, I think that we have multiple competing ways to understand it. We have not agreed on the correct way. My way is Like I said, Duck, in the bar, you just have the beer And nobody agrees, right? That different But like like you said, we can make the prediction quite accuracy. People tested the prediction, they won the Nobel Prize for it last year. That was what the phhysics Nobel Prize was given for. And by the way, The whole reason we know and care about entanglement was because Einstein in nineteen thirty five, was trying very hard to figure out what really is going on, right? And he didn't quite succeed. He didn't get the answer there, but it's that drive to understand that led here. And ultimately what we can say, I think with some confidence is that the world is is not a bunch of separate particles doing their own thing. It looks like a bunch of separate particles under certain very clear circumstances. but in other circumstances like this entanglement business, it doesn't. It's more holistic than that. People like me who are advocates of the many world's interpretation of quantum mechanics, we have a very simple, straightforward way of talking about entanglement But there's other people out there who talk about it differently and you know that's great. That's what academia and intellectual curiosity is all about. Remind us of the many world's hypothesis because I think that's now one hundred years old. Right? We're we're in the centennial decade. of the major discoveries of quantum physics, the nineteen twenties So if you can just remind us what the many worlds, I think it was once explained to me and I said What do you smoke think's sure. that's what I said. When we teach undergraduates quantum mechanics, we say that The Quantum system has two different ways of evolving There's one way you can evolve when you're not looking at it, and that's what Schrodinger and Heisenberg and their friends figured out back in the day. But then just to be clear, I just to be precise I know how you're using the word evolve. But to a biologist, the word evolve means something completely different. So you mean it unfolds. The events unfold. Yeah, it changes, it has its dynamics, whatever it's doing, whatever its behavior is. then there's a whole other way that we need to describe that behavior When we make a measurement, when we observe the system, famamously in quantum mechanics, you can't predict deterministically, precisely with one hundred percent confidence what answer you're going to get. You can predict a probability distribution over different possible answers. And Einstein said, God does not play dice. That's what Einstein said, Yes, with the universe. O It kind of looks like You know, you are playing Dgas. I'm just saying, I'm just And by the way, what a presumptuous statement on Einstein's behalf. I mean, who knows? Sewn, didn't Neils Borg say I I stopp telling God what to do lly. I mean. Who's to say that God's not down on one me going popping needs a new pair of shoes? You don't know that You know that So wasn't Neels Bar? someomebody said it to Einstein. Wh who was it? I think it was Neels Bor. I think the better advice would be like don't play dice against God. You're not going to win. that's o. there you go. That makes sense. So What is this going on with this weird thing? you don't expect? measurements, observations, looking at things to be part of the fundamental nature of reality, right? You know It never was before quantum mechanics came along. So you can ask yourself What if like all of that was unnecessary? This whole idea that we need a separate rule for what happens when we measure something. What if you just erase that from the rules of quantum mechanics And the answer is that what you find is that every possible measurement outcome comes true in a different world, in a different part of the overall quantum universe you get parallel worlds where different measurement outcomes are true. That's when I asked what the guy was smoking. Wow.. Now wait. so these different worlds are in the same realm, is that the case? or are we talking about completely different unfoldings that create completely different scenarios that make the whole thing work O another way to ask that, do you have access to these other worlds? There you go. Thank you If you have an iPhone, you can download an app called Universe Splitter And if you're ever stuck on what decision to make, you know, shouldhould I have a hamburger or, should I have pizza for dinner tonight or whatever? As the universe splitter and we'll come back with an answer and you can be guaranteed that there's a whole notother universe which you can never interact with or talk to. in which you do the opposite thing. So there's it split in that instant, right In that instant. Yes. Yeah at the decision instant. Okay, okay It's a physical quantum process. and that's because of the entanglement because they couldn't exist simultaneously. They have to exist in those positions. the time of the decision so that when one does it, the other does the opposite or when one does something, so there's an action and there's a reaction. But there can't be action, action. It has to be so that they're existing and then reacting differently. Is that Seaan Chuck is about to blow a gask. No because you're freaking me out man You are freaking me out This is not anything that we bump into in our everyday lives. If it doesn't make you a little bit uncomfortable, you're not taking it seriously. Okay. All right. Wow I've always wondered why Hollywood aliens tend to have two eyes, a nose, a mouth, ears, head, shoulders, neck Arms, legs, fingers, toes Maybe it's because an actor is donning a costume That's one of the reasons why I wrote, Take M too yourour Leader It's to explore All that is possible in this universe beyond what has yet to be imagined Hollywood So that for your first alien encounter You'll be prepared You have some anticipation of what they could look like What kind of ship they arrived in What you should or should not say or should or should not presume I narrated the audiob book prrint version is available as well You betteret get the book now before you have that first alien encounter. Be afterwards It'll be too late Aima as unpredictable But you can flare less with ellyiss, a once monthly treatment for moderate severe eczema After an initial four month or longer dosing phase, about four in ten people taking EBGLS achieved it relief and glare are almost glare skin at sixteen weeks. And most of those people maintain skin that's still more clear at one year, with monthly dosing. EBlS Libap LBKZ a two hundred fifty milligram per two milliliter injection is a prescription medicine used to treat adults and children twelve years of age and older who weigh at least eighty eight pounds or forty kilograms with moderate to severe eczema. Also called aopic dermatitis that is not well controlled with prescription therapies used on the skin or topicals, or who cannot use topical therapies. EBGlS can be used with or without topical corticoosteroids. Don't use if you're allerg to EBGLIS. Allergic reactions can occur that can be severe. eye problems can occur. Tell your doctor if you have new or worsening eye problems. You should not receive a live vaccine when treated with EBGLS. Before starting EBGLS, tell your doctor if you have a parasitic infection Ask your doctor about EBlS, and visit Evlus. liily. com or call one eight hundred Lily R X or one one hundred five four five five nine seven nine. Paramount Plus is now the home of all your BET favorites. That sounds nice. with all new episodes of all the Queen's men. You stand up when you talk to the Qeen. Plus a whole new world of movies like Gladiator two. I must have power. Original series like The Shy. Life comes at you fast, whether you ready for it or not. In live sports like UFC. unbelievable New home, Welcome to Paradise. Same family. That's all that matters to me. Your BMT favorites are now on Paramount Plus, and suubbscribe now Brian Reynolds here from MidMobile. I don't know if you knew this, but anyone can get the same premium wireless for fifteen dollars a month plan that I've been enjoying. It's not just for celebrities, so do like I did and have one of your assistant's assistants switch you to MintMobile today I'm told it's super easy to do at mintmobile d. com slash switch. Upfront payment of forty five dollars for three month plan, equivalent to fifteen dollars per month required. intntro rate first three months only, then full price plan options available. taxes and fees extra. Fful terms at mintMobile d. com Let's get to the question. Okay, man. She got dest this. This is already good stuff, Boy, I'll tell you,. I'm so mad I didn't Have an edible before this show Okay I really should have taken a gummy before this one So go on. All right, here we go Again, these are from our Patreon supporters. Thank you all for What you do for us? All right, Chuck, you got your iPad there, all right? I do. So here we go. This is from site says, Hello, Dr. Tyson, Dr. Carrool, Dror Haa first time Patreon member. I know, right? First time Patreon member here huge, huge fan. I am S I'm wrg Lakajur. Luck how did you from India Chuck, if you get my name right, I swear to God, I will double my Patreon membership You know, well I I guess you have you're in no danger there, are you? Yeah, I think he's gonna have it after what you just did to his name, but right. That was funny My question pertains to Dr. Carrool's research, which says that the universe is infinitely old and Big Bang is just one of many events resulting from quantum fluctuations of a vacuum energy in a cold this slitter disitter space Please throw some light on what kind of space is this How can I visualize it better in order to understand it more fully Good, very good. I wanted, you know, hanging out on the wrong street corners. I don't know where they where they pick these things up. Yes, this is all driven by the very famous philosophy question Why is the past different from the future? Why is there an arrow time because the fundamental laws of physics have no arrow of time in them The answer is entropy And the second law of thermodynamics, the universe used to be more organized, lower in entropy The whole history of the universe is just entropy increasing, disorder and chaos developing all around us. We're all going die. That's the It's not your fault necessarily, but you're contributing to the disorder and chaos all around us And that started About fourteen billion years ago near the Big Bang. att the moment of the beginning of the universe, our universe was exquisitely orderly. It doesn't necessarily look that way, but you run through the numbers and it's true Why Why is that true? Why was the whole universe so orderly? And so I've long wondered about this and I wrote a paper yearsars ago now with a woman who's a graduate student of mine at the time, Jennifer Chen where we proposed that the Big Bang was not the beginning. of our universe. Other people proposed that in different context, but we made the case that you don't need a fine tuned, special, organized, low entropy beginning of the universe. The universe can be eternal, it can last forever But what happens is it empties out, just like our universe is doing. A universe can be completely empty. The future of ours will be but it still won't be perfectly quiet There are still quantum fluctuations that can lead to whole new universes coming into existence And as that happens, they all start in low entropy conditions and the entropy grows and gives that little part of the universe an arrow of time And the fun part is far, far past, the same thing happens but in the other direction. So there's sort of a symmetric shape to the universe, where the future is a story of more and more universes being created and the arrow of time pointing in that direction. past is a story of more and more universes being created with people in them who think that we are in their F I'm gonna tell you right now. is If Psi understands what the hell you just said, then they need to be the co host of this show becausecause I am not gonna lie. Rait, wait, so Song. Wait, Song. So you lost at the end. I I need you to do the end again. So Sean, what you're saying is there's some symmetric point Aong these universes and these time continua where We're in one direction where entropy increases In principle, there's a whole other realm where entriy decreases. from our point of view from the people living in it They will always see entropy increasing because we always define the past as the direction in which entropy was lowered. So it's a big U shape that is perfectly. let it now. So we're in their past. because they're looking at us and seeing a decreasing entropy, which is indicative of traveling backwards because we're moving towards a more ordered universe. But we cannot be moving towards a more ordered universe if we are moving into the future because we are always moving towards entropy. So if you are observing that, then you are in my I am in your past So because you're looking at me going towards order That's it. We're done Yeah, man Yeah T That's insane It you're blowing out the volume level on the microphone. That's insane Oh my God. Okay, wait., so Sean, before we get to the next question. what Um, theseese are ideas Is there any way to experimentally verify any news. Well, we're trying, but the short answer is we don't know yet. We don't have It's not like a no to say it. No. It's very much not a no. Oh, okay. All the words, Deil, Th all the words matter here Okay. And but this is a more a broader idea, right There are plenty of tentative preliminary scientific ideas, which are too ill forced yet. I'm with you. Predictions. Einstein's gravitational waves Reichstein's gravitational rings Yeah I'll give you that. We'll get there. We will get there. send money. We'll do it. justust trust us. And your lifetime. And lifetime is getting shorter every year, so I don't know. All right, Chuck, what else you All right, let's go on to Doug Sherman. Doug Sherman says, Hi, Neil, Hi, Sean, Lord Nice Uh the Doug this is Doug from Frisco, Texas. All right. All right, way to go, brother Um, Doug says I thoroughly enjoyed Seaan's debate on God and cosmology against William Lane Craig, although I'm still trying to get my head around everything Sean explained. One amongst many arguments, I found interesting was Seaan's rebtal against mister Craig's technological argument that the finely tuned universe was evidence for the existence of God. I don't recall the specifics, but I believe Sean stated that in some models The finely tuned universe approaches. Then he says, Could Seaan once again go through the perspective of the fine tuned argument? I also reject the technological argument. for more simplistic reasons than my flawed brain can rationalize So just for context, William Link Craig is a opponent of I'm basasically a God created universe And he's not Bible something person in such a conversation as others might be He's trying to stay grounded in the natural world taking you to a precipice where you say, Okaykay, God must be there So I'm pretty sure Sean wouldn't debate just anybody on that subject. So Wiam Ling Craig has some abbating respectability in that regard. Did I characterize your Y opponent accurately, would you say? Yeah, that's fine The fine tuning argument for the existence of God is what I think is the best argument for the existence of God I also think it's a terrible argument, but still it's the best of the ones that they have. So I'm glad when they refer to it. And the idea is that you look around the world, the world in which we live, the universe that we find ourselves in, and you say, there are features of this universe that need to be the way they are in order for life to exist If they were different, life couldn't exist. They easily could have been different Right? The things like the amount of energy in empty space could have been so large that it would rip planets apart before they ever form. We seem to have gotten lucky. We seem to find ourselves in a universe that allows for our existence And so the argument is, I know why. it's because God did it, because God created a universe in which that's possible very common counter argument is, well, it also could just be a multiverse, right? You're not in all the others to have this conversation. R. So they help play an explanatory role in accounting for why our universe look so fine tuned. Two things going on here. One is the proponents of this argument tend to exaggerate the degree of fine tuning that they need. And that's what the questioner is referring to. There's certain things that Lillam Laye Craig and others say, oh, I just don't get it. That's so fine tuned. but you can raise your hand and say, actually physics has completely explained that one now. We don't need to go beyond the realm of physics to account for that. But in other ways, it still looks fine tune. And my favorite rejoinder is actually This is a great argument. for the non existence of God Because if God existed and God created life God is not beholden to the local laws of physics. God can create life however God wants to, because he's God God could do anything. You don't need the physical conditions to allow for the existence of life unless God does not exist. So All right, now me let me just ask a question here because just just to further clarify. If instead of needing the laws of physics The laws themselves are a reflection. of what God has done So it's not necessarily that the laws are needed It's that the laws exist because they just happen to be a byproduct creation itself That is completely possible. and Neil will raise us hand here and say, how do we observationally test that hypothesis? Okay. listen, I'm one hundred percent I'm on board with that. Okay, good I just wanted to make sure that that could that that could be an argument to be had.'s But look for the last five hundred years, as science has done more and more to explain why the universe is the way it is The role for God as an explanatory move has gone away, has diminished, right? And so you are left continues to do so. Yes. And so you're left with, if you want to believe in God and there's plenty of very, very smart people who do They tend not to rely on God to account for thingsings that we observe in the natural world Gotcha Wow fascinating stuff All right, J, keep going. We've only gone through two or three questions. Let's see we can We just have to have Sean back. That's all this stuff is too good. We can't rush. We cannot rush through this. This is too good. At one point get a double wide episode with him maybe. Yeah Yeah, yeah, absolutely All right, here we go. Tom P. Knights, says this. Hello, I'm a Patreon supporter of both Start Talk and Mindscape Great to see Seaan on the show Do Vos in the cosmic web likeike The Irredanus supervoid violate the cosmological principles. be the cause of these structures Thank you ' for your service Okay' Good one Eerodinus is a constellation. I think it's a waterfall or it has something to do with water My memory serves. But anyhow Od Seawn, what you got there This is a great question, but there's a lot going on here. I'm going to try to keep it brief here You know, there's something called the cosmological principle that says that if you squint and look at the universe on very large scales, everything looks the same everywhere, right? The same number of galaxies and whatever y thing to call a principle because it's not a principle. It's just a fact that you see about the universe. It could easily have been otherwise. Eespecially because it's not exactly true. and that's what the question is getting at. There are places in the universe where matter is very dense. There's places where it's very empty and so forth. The way that modern cosmologists think about this question is to say early universe, it was Even smoother than it is now, it was very, very smooth. There was only a difference in one part in one hundred thousand as you went from place to place. Number one Why was it not perfectly smooth, but number two, why was it pretty darn smooth? And number three How did it evolve? using the word evolve again, from that condition one hundred thousand years after the Big Bang to our conditions now The last one, how it evolved, is the one we have the best handle on. It was gravity doing the work. Gravity turns up the contrast knob on the universe. So if you have a slightly emptier region, it empties out, have a slightly heavier region. It collects matter onto it. And so we went from very faint ripples, if you look at the cosmic background radiation to these very vivid voids and galaxy clusters that we see today We still don't know where those first ripples came from. Inflationary cosmology is a favorite thing to talk about, but that's a wholeother episode Wow He So I like the way you said that. you we we observe these F fluctuations in one part at one hundred thousand And you say, well, how come it's not perfectly smooth How come it's one part in one hundred thousand? How come it's not anywhere near that today?ight? It's a fun way to think about that problem. becauseuse it's easy to say, well, here's the answer and then move on. But wait a minute. Why isn't it something else? Yeah. Right. And notot enough of that goes on, I think. Well, it's once again, a reflection of the fact that the early universe had low entropy because gravity was so strong in the early universe more common generic random configuration would have been wild fluctuations like black holes here and empty space there, and so The fact that it was so smooth does kind of demand an explanation, and we're not sure what the explanation is Mhm Okay. Keep us going checked And that one was from the overlap of the Venn diagram between Mindscape and Star Talk. Love it ama. as unpredictable. But you can flare less with eliss, a once monthly treatment for moderate severe eczema After in an initial four month or longer dosing phase, about four incent people taking EBGLS achieved itch relief and glare are almost cleare skin at sixteen weeks. And most of those people maintain skin that's still more clear at one year with monthly dosing. EBlS Livap LBKZ a two hundred fifty milligram per two milliliter injection is a prescription medicine used to treat adults and children twelve years of age and older who weigh at least eighty eight pounds or forty kilograms with moderate to severe eczema. Also called aopic dermatitis that is not well controlled with prescription therapies used on the skin or topicals, or who cannot use topical therapies. EBGLS can be used with or without topical corticoosteroids. Don't use if you're allergic EBGLS. Allergic reactions can occur that can be severe. eye problems can occur. Tell your doctor if you have new or worsening eye problems. You should not receive a live vaccine when treated with EBGLS. Before starting EBGLS, tell your doctor if you have a parasitic infection Ask your doctor about EBlS, and visitvlus. liily. com or call one it hundred Lily R X or one one hundred five four five five nine seven nine. Paramount Plus is now the home of all your BET favorites. That sounds nice. With all new episodes of all the Queen's men. You stand up when you talk to the Queen. Plus a whole new world of movies like Gladiator two. I must have power. Original series like The Sy. Life comes at you fast, whether youre ready for it or not. In live sports like UFC. unbelievable home, Welcome to Paradise. Same family. That's all that mattericed to me. Your B andT favorites are now on Paramount Plus. and suubbscribe now Ryan Reynolds here for MintMobile. I don't know if you knew this, but anyone can get the same premium wireless for fifteen dollars a month plan that I've been enjoying. It's not just for celebrities. So do like I did and have one of your assistant's assistants switch you to MintMobile today. I'm told it's super easy to do at mintMobile dot com slash switch. Up frront payment of forty five dollars for per three month plan, equivalent to fifteen dollars per month required. intntro rate first three months only, then full price plan options available, taxes and fees extra. Feful terms at mintMobile dot com d Hey, this is Kevin the Samaler and I support StarTalk on Patreon You're listening to Startalk with Neil DeGras Tyson This is Malcolm Mar Fon and Malcolm says Hello, Dr. Tyson, Dr. Carol. And shock, maybe? Okay. I love these people, man. I love you, Chuck, no matter what they call you. I no I know. Well, Malcolm Marfon here all the way from Trinidad and Tobago And he s Oh nice. He says, doct. Carool, I came across your twenty eighteen paper. Why is there something rather than nothing and thought, Wow This guy's really dedicated to the lot of brain power to the concept of nothing Now, since you've clearly become an expert in nothingness, can you shed some light on the various layers of nothing spepecifically, how do these layers of void stand apart and how are they intertwined with the headspinning realms of cosmology and quantum mechanics? PS, can I get a philosophy or physics degree with nothing from Nothing for my thesis I think our questioner missed the point of the title of my paper, which is that there is something like you know, we can contemplate There wouldn't have been anything and there's just nothing. but What I say in the paper is Can we really contemplate that? I mean I think that we have this informal training from our everyday lives, right? where we have boxes with things in them and boxes with nothing in them. And so we think that there's an option. There can be things or there could be nothings When it comes to the universe It is not at all obvious that there is an alternative to the universe existing. What does it even mean for nothing to exist. How does nothingness even exist? I mean, that's kind of what I'm getting at in the paper, which is that it's not at all clear The reason why the universe exists is the kind of thing that has an answer to a why question Mbe maybe we just have to accept it as a brute fact and be lucky about it. I do think this stuff is fun to talk about, but I don't think that U it is nearly as down to earth and simple and physical as certain physicists who like to talk about this make it out to be. It's fundamentally a philosophy question. wait, but John If there were no quantum physics In principle, you could talk about space as having no particles or none of these virtual particles that quantum physics forces into it You just say remove the atoms and all known particles That's as pretty good and nothing as anyone would hope to describe, isn't it? No, it's something, it's space It has could you have a word for it Okay. you call the empty space space and I call the empty space nothing Aren't we just semantically differing there, not Fundamentally differing? Is empty space three dimensional I don't know I' needention You' just' w want to answer it becausecause you know, let's say let's say's three dimensional and exist on a time continuum shurance. Oh it has a property then. It's not nothingness. There's a way it could have been different. Well you invoke a way to measure stuff in it. I wouldn't call that an inherent property of the empty space It it's different than four dimensional empty space. Okay, so how about this? How about this Okay Uh, again One of the reasason why I don't Like arguing with philosophers, becausecause ultimately it comes down to how you're defining the words that you're using in your sentence. in so many of those arguments Let me just say If we define something versus nothing As something is, there's a thing there And I take everything out so that as Chuck said, there's R you said, there is no thing, nothing there, then that's nothing. Okay. now were now you're saying There's a grid system there that we can invoke where it's inherent. So that's a thing. Okay, so now I add to my inventory of a thing, particles plus grid system Okay, fine, then that's there. So now we have to ask, can we take away the grid? What I think is a more interesting question is Do the laws of physics apply in that volume Therefore, it can't be entirely nothing because laws of physics apply, even though there's nothing there to manifest Oh. Now you're getting deep. so I like it because You're invoking not what the system is, but counterfactual properties of what would happen to the system if you changed it a little bit, which is fine. It's a fine thing to do Look, you're absolutely right that there is no pree existing definition of the word nothing to which we're referring here. You could have different ideas. I think that the deepest level of this question is why is there a universe at all versus complete non existence, not even space I mean, even you had to preface your question by saying like, imagine there was no quantum mechanics. and for that matter, secretly imagine there's no general relativity either because o. Yeah.. you're throwing away all of known physics to even ask your question. But of course Within known physics, you can ask plenty of questions about Why isn't space empty? Why is space three dimensional? Those are perfectly good physics questions. It's a little bit different than the question of why there's a universe at all. You can ask the both of them separately. It's not a right or wrong thing to ask. Right All right Well, that's smart. What a great question. Yeah Yeah because when someone says, why is there something rather than nothing? and I look out in the universe which is mostly nothing I say, there's a lot of nothing in the universe. just So whatever something we have that's is's side by side with a lot of nothing until you start invoking other definitions for what nothing can be. So that's my own rep there. Well, there you have it, Malcolm. We have discussed your question and we we have achieved nothing P you p All right. All right, keepinges Javier Ortega, who says Hi, you guys are just the best greetings from my artificial Limbs development lab in Panama Just a quick question that will not let me sleep too the speed of light We can only see the past while looking into distances of the cosmos. How do we know we are in the quote unquote real present We sense everything with delay, even short distances. Also, there's a delay between our senses and our brain. Are we sure that we perceive now as now? Maybe it's just something relative to us like movement. Maybe we are five hours in the past or two hundred million light years in the past according to some other arbitrary timeline or other alien beings that could travel instantly to. Everybody's been smoking Before this, let me tell you, man, I told you That's you He says, I hope you read this message from the past Please che your dinner. He makes an interesting point that What does the present even mean everything we do to interact with the world has some kind of time delay Like I'd like that idea of the brain our understanding, our senses are That's true. , you know, my hand is not as it is, it as it was a billionth of a second ago what does it even mean to talk about the present Yeah, there's a science anser here and a philosophy answer. I'll give you the science answer because it's quite good our brain does not Pceed pres. our brain puts together a picture of the world that is on a slight time delay. like our brain wants to be able to bleep out things that it doesn't like. If you watch someomeone dribble a basket And they're right next to you. You will see the basketball hit the ground and you will hear the thump of the basketball against the ground and they coincide. They go along with each other. If that person walks away still true. You see and hear same thing at the same time, even though the light gets to you much quicker than the sound. And what happens is if they keep walking away, suuddenly, they will go out of sync the vision of the basketball hitting the ground and the sound of it because that happened suddenly. so your brain was correcting for it. Holy Y. Because your brain corrects for it as long as it's near enough, your brain says this is all now And you can even measure how much it is. It depends on what sense you're talking about and what perception, but roughly think about forty or fifty milliseconds of time is a little window in which your brain collects things and says, I'm going to put this together into a picture of the pres. A millisecond is a thousandth of a second forty to fifty thousandths of a second wouldould be like five hundredths of a second. There you go goodood. Okay. Excellent W wait, so what you're saying is there's a point where the brain just gives up recreating the present and said, I can't compensate for this. It's too hard. It's too much. I can't do no more So you do That was it D without me. Oh God, it's just. I can't take it So so so this is an experimental result, Sean You know, look, as I'm sure you already know, neuroscience, biology, psychology. That's a whole frontier right there.ike way harder than physics or astronomy. wayay harder, way harder Yeah. Okay. I did not know this. So interesting So the brain constructs a present so that we can