Spacetime, Premonitions, & Brachistochrone Problem with Neil deGrasse Tyson & Charles Liu

Is our experience of time a result of our perpetual movement? Neil deGrasse Tyson and co-hosts Chuck Nice and Gary O’Reilly explore spacetime, metaphysics, the Brachistochrone problem and more with astrophysicist Charles Liu.
We explore space and time graphically, what the experience of time is for a light photon, and the tired light hypothesis. Charles argues why we’re moving at the same speed of light. How do people age in a spaceship going warp speed? We discuss how warp speed creates a breakdown in causality.
We talk about linking the universe to metaphysics and whether dreams hold significance. How is the cosmic microwave background constant when there are hot stars? How are some black holes bigger than others if they are infinitely dense?
Why do rockets launch up instead of horizontally like an airplane? We break down the Brachistochrone problem and the fastest minimum energy path. Could you launch a rocket to space through spinning? All that plus, we discuss our favorite inventions from Star Trek that came true.
Thanks to our Patrons Marcus Karlstad, Vincent Zimmerman, Ryan Lambert, Carolyn K, Stefan C. Villafana, and David Churn for supporting us this week.
NOTE: StarTalk+ Patrons can listen to this entire episode commercial-free.
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About StarTalk:
Science meets pop culture on StarTalk! Astrophysicist & Hayden Planetarium director Neil deGrasse Tyson, his comic co-hosts, guest celebrities & scientists discuss astronomy, physics, and everything else about life in the universe. Keep Looking Up!
#StarTalk #neildegrassetyson
00:00 - Introduction
2:50 - Does Time Come From Movement?
10:42 - How Would People Age at Warp Speed?
15:28 - Science, Dreams, & Metaphysics
25:10 - Foreground Contamination & Cosmic Microwave Background
27:10 - The Size of Black Holes
33:20 - The Launch Path of Rockets & The Brachistochrone Problem
42:40 - Favorite Technology from Star Trek

[@StarTalk]

Star Trek fans, what's your favorite prediction of the future that came true?

[@sandyago4735]

That the original crew would get old and fat

[@quantumphysics5728]

i still don't know why did you not upload video on Chandrayan 3 ❤❤

[@NAFOSergee]

That ruzzia would FA and FO

[@lymanmj]

That superstitious indereducated folk would leverage their collective elective ignorance to attempt a takeover of our democracy.

[@totalpr0st]

cannabis is legal in Germany

[@diegofernandez4789]

When Charles Liu is present, the high quality of the show is guaranteed. Great episode!

[@swis]

His answer for the dream about the punch in the face on the soccer field was so respectful and interesting.

[@michaelccopelandsr7120]

Neil and Chuck for 2024!

[@KC-nd7nt]

Yeah .... Naaaaaa

[@dbz_feats7723]

@@KC-nd7ntno one asked you

[@rolandorzabal1955]

Yeeeeeessssssssss

[@manishdewani233]

no brain can be normal in politics, do you wanna lose him?

[@loccc88]

Dude you post this in almost every video.

[@frogz]

ANY EPISODE WITH THE GEEK IN CHIEF IS A GOOD EPISODE!!!!!!

[@serarokkit]

Thank you Neil and Chuck for making learning an enjoyable experience 😊

[@SL-vs7fs]

Chuck is always killing it with his jokes. From the deep to the superficial. 😂 👏

[@jmanj3917]

...Usually... 🤣

[@JBG-AjaxzeMedia]

love it when Neil is also learning, just shows that there's always more to know, knowledge is infinite!

[@DanLee-du3kg]

This episode was so cool! I'm always impressed with the returning champ, Charles Liu. I'm amazed at his compassion, his calm cool and collected demeanor and sharp as a tack brain. Same for Neil. And Chuck Nice came up with some awesome questions in this episode.

[@VikasDAce]

The best quote from Neil De Grasse Tyson is - "We do not know" and that is something that keeps the light burning 💥

[@racoonchief]

Okay but what does it have to do with this video?

[@VikasDAce]

@@racoonchief not much but related to the overall picture.

[@KramerEspinoza]

Wonderful guest.Warm voice and extremely knowledgable. I really enjoyed it.

[@phillipwayne7516]

Come for the knowledge, stay for Chuck!

[@MichaelSmith420fu]

The Chuck never fails to make us smile

[@yos025]

Startalk is great but when geek n chief Liuniverse is in. Is about to get awesome and deep. Keep bringing him in!!

[@rbee6507]

This is...possibly my favorite episode, just in the first 10 minutes! Pretty good understanding of time and how we interact with it already, but thinking of it as Dr. Liu outlined just put it in a whole new "light". Truly is the final frontier of understanding our universe if we grasp that dynamic. Absolutely thought provoking in the highest order. And so many other points. I have so many questions to submit!

[@ZeroOskul]

I am so grateful that Charles Liu gives us the distinction between geek and nerd. Geeks know cool stuff and are obsessed with the weird. Nerds know all kinds of boring stuff that might save the world and are obsessed with knowing boring stuff that might save the world.

[@patriciabarr2161]

This was one of the funnest StarTalk Special Editions I've watched thus far. Loved it! ❤

[@clbcl5]

I believe it was Steven Wright who asked....If your traveling in a space ship at the speed of light and you turn the head lights on, what happens?

[@kimjohnson4278]

Neil covered that on StarTalk. Relativity. The light shines in front of you just like if you were standing still.

[@EmpyreanLightASMR]

@@kimjohnson4278 I don't know know if that's 100% accurate though. Not a physicist, but Wright's question and your reply make sense up to and including 99.999999...% the speed of light. I think the actual speed of light would be asymptotic (just using the word to mean unreachable) because if you DID reach the speed of light, your mass would essentially increase to infinity and there'd be no headlight to emit light anyway!

[@skywatcherextraordinaire7014]

Great question i think they wouldve already turned on, in the exact moment that you reached 100% the speed of light if you intended on turning them on because; Time slows down when you travel faster and faster but time doesnt exist at 100% the speed of light, so for photons, so if you were going to turn them on they would automatically know and already be on and if you werent they never would be and their is no having them off and then turning them on at the speed of light because the information is exchanged instantaneously just like entangled particles in quantum physics thats my theory.

[@Nunya_Bidnez]

Charles is not a Geek. He is a Stellar Human

[@morlin101]

Who isn't these days tho

[@morlin101]

Charles are you you have to be me Charles is just very aware of himself in my hive for the geek and chief is a trinity and would be surrounded by The source Wall

[@morlin101]

Brought there's a Galaxy out there in Aquarius that I nose for me and it is called atoms for peace

[@morlin101]

I knew it the light has always vibrated from the stars and so it is the speed of light serving as as like a substrate for an even more complex information highway which infor travels at the speed of light

[@morlin101]

OMG r u Atlas

[@joehopfield]

Love the brachistochrone - trajectory connection! Thanks Dr T.

[@sujimtangerines]

OMG I've never heard anyone else question how dreams might connect to the universe... For decades I've had the feeling that my dreams are just the actions of the me in some other universe. That I'm seeing them, experiencing them sometimes, via some property of quantum entanglement.

[@un_lucio]

I was shocked no-one mentioned Star Gate as a universe with wormholes 😲

[@stevewise1656]

Wish the show was still on tv. There's nothing like this on weekly.

[@monkerud2108]

its pretty fun to think about the fact that racecar drivers essentially solve a more complicated version of the brachistochrone problem by learning a new track. also its fun to try to do the problem with angular momentum, like a wheel rolling from one point to another, does it change?

[@Astronomator]

To put it more simply: Everything is moving through spacetime at the speed of light. If you're not moving through space, you're moving through time at the speed of light. And if you're not moving through time, you're moving through space at the speed of light. And everything in between is everything in between.

[@LEDewey_MD]

How on Earth did I miss this episode of StarTalk when it was uploaded?! Packed with profound questions, amazing answers, and incomparable humor!! ("SpinLaunch" is the name of the aerospace company attempting to cut costs of launching payloads into space using centripetal force.) Great show!! :D ❤❤❤

[@JaghataiK]

Neil telling Chuck to “let the man speak” is hilarious!

[@growthisfreedomunitedearth7584]

ironic for sure

[@floatingshoppinglist5193]

awesome episode guys. wanna see more of this.

[@Itsallfun3000]

Great show I always love Charles and his calm manner.

[@alexanderdede6354]

Man, I love the amount of subtle puns and nuance of Professor Charles' conversations.

[@bitwise2832]

Another excellent production. Thanks to all of you.

[@MamaGemini68]

Mr Tyson & Lord Nice, thank you so much. I have always loved science since the 4th grade. Growing up in S.E., D.C. my life was very political with both parents working in politics but science held a special place in my heart & was always on my mind. Thank you, thank you, thank you 😊😊

[@sekaramochi1944]

Omg time rocket science and Gary and chucks too, pure love❤

[@jrmylnrd]

Always enjoy the topics and discussion. Especially when the scale of geekiness is referred to as infinite scale. Made me smile because I immediately started thinking about geekiness being relative to the speed of our thoughts (like time with speed).

[@whydidmyhandlechangefromAlice]

I love how respectful Charles is toward other people’s beliefs. I could never be that diplomatic, someone starts talking about New Age stuff and my eyes automatically roll, like Westphal’s sign.

[@dawnhansen7886]

You guys are Educational Entertainment to the MAX ❗️ ThankYou. ❤

[@middleeastobserver6023]

Lovely. Watching from Iran. The only two Americans I love, Neil & Chuck.

[@NielvanSteenderen]

This guest is next level smart, and we are used to super smart. Incredibly humble too, I am really impressed with this lovely human.

[@mikejettusa]

Entertaining and enlightening, great combination

[@eranlevy4082]

Very interesting, mind provocative - and funny! Thanks for this excellent content!

[@deenice616]

Awesome! Thanks for answering my question guys about the universe, time, and dreams! Love the show.❤

[@StarTalk]

Our pleasure!

[@DukarioBerlzec6]

@@StarTalk well star talk I wanted to know what happens if I build a ISS size object and it fits into a falcon 9 And it consists of a quantum computer And sollar panel s array then there is the necessity of cooling system and ECT but we put it in high solar Sun orbit and there we must might start to begin building a Jupiter's brain in Dyson sphere but as I Finnish

[@DukarioBerlzec6]

@@StarTalk I start to realize it's a lot easier and cheaper to build it on earth than in space and especially so close to the sun with minimal protection and its lots faster and easier on Earth to build a facility to house thousands then all the money to launch one to space so the only upside 5o strapping into a rocket and hurdling it to space is just to be able to say hey you've been working on this section if the son because it's piculuar well I have a parking space for 2 hour's so go look at the other side of the sun and you'll find beauty and cerenaty and I will get mankind to validate my parking ticket forward to colonize that PATCH of skies Niel deGrasse Tyson for that's the enthusiasm we need not to wait till oh cold war with China let's band together and go to space np it's to validate my claims and to block the most beautiful sceneries with a colonial outpost forward brother's the astronomers will not suffer without knowing my parking validation on my Tesla and or future starship like this isn't a ancient star Trek ERA Elon musk Plzen don't cancely Wright's to bear that flamethrowers you sold because if there are over civilizations out there I will show we are capable of toddler like magic tricks to them like tiny over here with his bubble gun (flamenwarther)

[@georgefeener8682]

Hey lord chuck you have the best job in the world working with these guys must be a blast

[@techfan7808]

Love Chuck keeping it light for us lay people

[@elizondorj]

Great! Chuck Nice and Chuck Liu! If Chuck is in the show, it is a good show.

[@clueless4085]

36:25 The brachistochrone problem was posed by Bernouilli in the 17th century. In case anyone wondered.

[@hotplasma]

In term of Star Trek tech invention, i think translation apps on our phones are perfecting their way to Trek's universal translator.

[@Sammasambuddha]

Yup

[@hotplasma]

@@OscarLangleySoryu In Trek's universe, they did attempt to address the universal translator limitation. TNGs episode Darmok (S5, Ep 2). But I digress. 🙂 Within Earth cultures, using language databases, I think a Trek universal translator scenario where one's words are instantaneously translated thru an app and/or devices allowing for (mostly) seamless conversations is almost there. I say mostly because there still might be situations when some meanings are lost in translation.

[@Sammasambuddha]

@antiMAGA And just the last ten years, google Translate (now with AI (bard) is quite accurate and quick.

[@louisel.sinniger2057]

What amazed me about Star Trek years ago and how it came true is the communications, i.e. talk out loud and request things happen Hey Google, or Hey Siri. Thermal thermometers just to name a few. I LOVED all that and I knew that some day these things will come true. Thank you Space Program for these advancements! To me the program moved us forward in MANY ways that most people have NO idea where they came from. Love science & technology. NEVER boring!

[@topspacesource]

Great show about space time and dreams. Dreams are fascinating by themselves.

[@msjadhav5192]

For me is the most amazing thing about dreams, that i see clearly people i have never ever seen i my life for sure

[@dianacanales2526]

You guys are all awesome!!!! Love it!!!

[@disturbedrebirth]

This episode was so much fun.

[@carolineraymond9123]

Chuck Liu !!! Missed you!!

[@sekaramochi1944]

Pure love Neil Charles Gary chuck Please please please never stop ❤

[@jaydavis9812]

By far one of the best episodes! Thanks NDT and Chuck!

[@BoogerBrain]

I didn’t know so much of this

[@jaydavis9812]

@@BoogerBraintruth! It shifted my perspective of time.

[@rayaterry5365]

I was today years old when I finally understood the theory of special relativity

[@schnioula]

*I love smart humans! Wholehearted* ❤

[@zohatahira3992]

I love this episode.

[@DiamondRidgeMusic]

Pretty sweet video concept with the 15 vs 150

[@sabinrawr]

For the first question, I'm a little bit surprised that this wasn't also framed as the way many people (like me) think of Time Dilation: the flatter your curve in the space dimension (faster speed), the less you can move through the time dimension, therefore you experience less time. The hyperbolic math comes out of the observation that the time dilation effect becomes increasingly extreme at an increasing rate as you approach the speed of light through space. Next, i would disagree that warp drive, such as an Alcubierre or similar, necessarily violates causality. While it's true that you might arrive at your destination before the radio signal, that doesn't imply that you arrived before the signal was sent. In the same way that when we eventually watch Betelgeuse go supernova, we will be observing something that actually occurred ages ago. While the Start Trek universe is full of timey-wimey hijinks, such as tachyons and Q, was drive isn't one of them. The warp bubble creates a pocket of spacetime within which time flows normally and is shunted to another place to be stitched back in. The bubble can move superluminally for the same reason that space itself is allowed to expand faster than light speed. The only piece of Trek tech that i don't see happening is the Heisenberg Compensator that allows the transporter to function without violating the eponymous uncertainty principle. My favorite, though, is the deflector dish. I don't know the details of the tech, but it sounds a lot like some of the ideas about how ancient Egyptians were able to move massive stone blocks that even today's cranes would struggle with.

[@RiseOfTheNew]

We see/hear you chuck 💯❤️

[@carloruiz2228]

Love the show guys!! I listen every night 🎉. But just curious, could you possible do a show on ghosts/pseudoscience? I trust science, but then there are people who say places are haunted like Alcatraz, old buildings, houses etc: places I would never sleep at. I would really love to hear the science of what these explanations could possibly be. Again, love your guy’s work! Both Chuck and Neil inspire all!

[@Brick_Squared]

The explanation of space time and the fourth dimension makes "going back in time" make sense e.g. traveling from Italy to the US at the end of a vacation.

[@ATLJonathanH]

Chuck makes this watchable.

[@Flying_Blind]

You can go into your dreams if you train yourself over time. I know because I did the experiment. A physic type guy was on Johnny Carson years ago and explained how to interact with your dreams. The 1st time I was able to enter my dream, I couldn't believe it, but I was there. And I was part of the dream, I knew them, they knew me, we conversed and interacted. I did it a few more times and just kinda forgot about it ever happening. But it did, I could do it now if I prepped myself for a few weeks or days.

[@twobirdsonedrone]

Looooved this episode!

[@tyronholloway1079]

One like is not enough, great job you blokes. 👏 Keep it coming 😊

[@stukskekrapuul]

It's fascinating how stars and their light that is going at the speed of light also move around the massive black hole so in that way the light they emit also goes around the center of the Galaxy(the massive black hole)also actually moving the light at those enormous speeds depending the stars location(far or distant to the center). Just fascinating 😅

[@allanw9206]

That was wonderful, thanks!

[@reportedstolen3603]

4:44 Charles smoking a little “Albert Einstein 1905” is amazing 😂❤

[@andrewm8429]

i just got my tickets to see Neil in Toronto!! 3rd row!! I cant wait!!!!!

[@CabbageAnimations]

Love the channel! You guys make science straightforward but interesting! Yes my picture is a Chicago dog from Chicago

[@johnherron3961]

Another good 1 guys! It's also possible that we do see into our future in dreams. Not everything is explainable by our current understandings.

[@trinaka]

I couldn't agree more. I dreamt of a terrible tragedy three hours before it happened. I have wondered if my mind picked up bad vibrations from the people that caused the tragedy

[@EmpyreanLightASMR]

One argument *for* seeing the future, that neither NDT or Charles mentioned, is lack of free will, which has been discussed previously on ST. so if the future is predetermined, then why couldn't the brain foresee that? If anything, it should be more impressive that our brain dreams as randomly as it does and doesn't continuously foresee everything.

[@AdrianaVRodriguez06]

Awesome video, great discussion 👏

[@rodney6045]

41:37 Love how Charles throws in Stairway to Heaven lyrics like it's part of the discussion.

[@earthoid]

I used to divide by zero on my Dad's Marchant mechanical calculator because it was fun to watch the gears and number wheels spin until they all reached their limit and stopped. That string of 9s was as close to infinity that the calculator could get.

[@BenGrimm977]

Charles is the best guest

[@alohaarianna]

I am glad I found this podcast!

[@nicko7238]

Welcome 😀

[@burtminshew4812]

Man...this was good!

[@jamesgreenler8225]

Great discussion 👏

[@sekaramochi1944]

Dude this video this on earth so we're moving through time into the future and in space too

[@broduh7630]

yeeeeeeeeeeeeeey Charles Liu back in the house, i really missed him

[@shayanchamas60]

This was great!!

[@SilverAlex92]

A bit on the moving on spacetime at light speed I was surprised you didnt mention. Under this theory time dilation is very easily explained as moving diagonally on the plane (assuming light is on the horizontal). As if, if you move at like 0.5 the speed of light, that is also consuming your "time speed", thus you feel time significantly slower. Same as being near a dark hole, the warping of space is so massive, your using your time speed budget.

[@MK.__]

Amazing video!

[@tanbui7869]

Lfg Tyson, Nice, O'Reilly, and CGO Liu!

[@rezadaneshi]

When you lay down a cup too close to the edge of a table and think it may fall and then it does, did you create the fall or predicted it?

[@chefboimacog5176]

Mr. Nices premonition example is a biiiiig mind blower.

[@andrewforbes1433]

It's a terrific example of how scientists and science minded people can still be completely blind to their cognitive biases.

[@umutkarakurt6017]

We all have a friend like Gary... No matter how scientifically you try to handle their "experiences", all they want to hear is "Yes, you are special." 😁

[@dianthaweilepp5294]

Chuck, you are GOOD!

[@JeromeEarthScience]

I LOVE that Dr Lu used his head as an example! I won’t forget 😂

[@wallykunz8641]

On the moon, with no atmosphere, does the most efficient path of ascent more closely approximate the Brachistochrone curve? Or, should you launch horizontally at a tangent and then keep changing the angle to match the tangent at the new altitude?

[@ThunderTurtle7]

The realization that a rocket trajectory is just the brachistochrone problem was very cool

[@FredPhillip601]

Phenomenon and Lucy I'm definitely going to have to check those two out Netflix

[@jamesgreenler8225]

Lots of lighting here in Arizona. The higher magnitude strikes form fulgurites. Really powerful strikes can eject globs of molten glass and leave holes over a foot across. This happens in less than a second.

[@AbhishekKumar-db5om]

Best podcast ever

[@user-mu6oc1rq9c]

The ice cream cone really got me 😂

[@kaaiy]

I know exactly what sir Gary is talking about because its not just the possibility of it happening but the details that don't exist as of your present experiences and recent memory. I had the same thing about a sports day that involved a boy I met on the day but I remembered his face which should not be possible because the brain does not create faces.

[@MarijaDakovic-ui7uc]

Wht a wonderful crew 😃❤️

[@sapnaa6576]

At 8:43 Charles says the vector is diagonal when we move. When we are in airplane or spacecraft. I am confused about this movement. If we are still still on planet aren't we moving indirectly? Planet around sun, sun around center of galaxy, galaxy moving away from other galaxies? What if we are walking on the planet? What is the definition of this movement?

[@maxwu3395]

I want to know if the perception of the passage of time is relative according to velocity and gravity, how do we measure the age of the universe? From whose perspective?

[@-_Nuke_-]

I loved that episode! :D

[@janicepedroli7403]

Have to go pick up medication but I have to hear this.