A Ripple in Spacetime with Neil deGrasse Tyson & Charles Liu

What if time had multiple dimensions? Neil deGrasse Tyson and co-hosts Chuck Nice and Gary O’Reilly answer grab-bag questions about Hawking Radiation, the speed of light, and how rare black holes are with astrophysicist Charles Liu.

We break down the time dimension and how multiple time dimensions would change our concept of the past. Learn about the ripples in spacetime and if the universe was a 1950s Jell-O mold. Where does Hawking Radiation come from? Could it be that a black hole does not have an edge? We explain quantum mechanical tunneling and explore the mystery of what creates Hawking Radiation.

How many black holes are in our galaxy compared to stars? Neil and Charles break down the rations of stellar objects for us. Is the residual effect of the Big Bang fueling dark energy? We also discuss why consciousness is likely not a cosmic energy that can be quantified.

Learn about the speed of light traveling through different media. We explore the possibilities of combining artificial intelligence and quantum computing. Can someday a computer solve its own problems? What are the ethics of combining these powerful tools? Plus, discover who Charles Liu calls when he doesn’t have an answer.

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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!

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00:00 – Introduction: Charles Liu
2:18 – What If Time Had 3 Dimensions?
7:04 – The Medium of Spacetime
10:40 – Where is Hawking Radiation Coming From?
14:43 – Quantum Mechanical Tunneling
16:01 – How Many Black Holes Are In Our Galaxy?
22:01- Is Dark Energy Left Over From The Big Bang
24:23 – Is Consciousness Physical?
31:24 – The Speed of Light in Different Mediums
38:22 – Who does Charles Liu Call?
42:55 – Combining AI and Quantum Computers

What I like about the Jell-O is you can you can send a ripple from one part of the Jell-O and that Ripple will propagate out as a Jello-O jiggle that’s right and jiggle its way across the pineapple Bits And if you’re in the pineapple you’ll feel a little jiggle as

As the wave moves Across this is Star Talk special edition Neil degrass Bon here your personal astrophysicist and as usual for editions we’ve got Gary O’Reilly Gary how you doing hey Neil yeah good if you didn’t know former Soccer Pro a football pro I guess they say that over in the UK a be

Turned announcer because he’s retired and recently married Very Yes congratulations happily married knew who knew it would last this long what six months not even not even that congratulations the first six months of marriage thank you Chuck Nice Chuck baby hey what’s happening Neil yes I feel bad because we’re checking in

With you you you’re doing a comedy stint in Aruba that’s right right now so right now you’re on this instead of being on the beach so we’ll try to make this quick for you I I I was on the beach and left left the beach don’t rub it in let

Me no don’t you have to make a thing out of it so what we’re gonna do is we’re g to have a kind of a cosmic queries but like a special edition edition of cosmic queries and whenever we’re in kind of grag mode I need some help uh and you

Know who we go to for that of course Charles Lou Charles welcome back hey hi Gary hey Chuck great to see you all I was not on the beach just now not on perfectly happy to be here with you all hey Chuck we’re of course all envious all right so Gary you you

Brought in the questions and you you curated the questions yeah we had more you told me we had more than a hundred 100 questions on this solicitation yeah and um apologies up front for those questions we couldn’t get to we only going to get about an hour’s worth of

This show so we had a flash through um and they’re again yep they’re all from our patreon patrons so thank you so much for your curiosity let’s start with Gina Martin shall we since since time as we know moves in a straight line can we consider time being one-dimensional from our perspective

That being said what would it look like if time had three iions just like space and is that even possible whoa GL you here Charles we’ll start with start with an easy one right uh the the reality is uh that we can indeed thank you for your

Question uh think of time as a dimension in fact the Rolling Stone sang a song about that time is a dimension right but yes the general relativistic assess of space time is Einstein general relativity yes Einstein general relativity um describes space and time as three dimensions of space one

Dimension of time now there have been some work over the years theoretically what if there were more than one dimension of time and what happens is complicated as you might imagine but the most signific that’s the answer it’s complicated next question yes well the the simplest well the most significant effect we would

Have in our lives is on causality right Neil as as you know we think of time passing as stuff in the past affecting what happens in the present and the future but not the other way around right if you have three dimensions of time and you can travel both forward and

Backward also left and right and up and down in time then you don’t know what the past is by definition you have to change your concept of what causes what because you can be dancing back and forth in a different dimension and something that you thought was in the

Past might actually loop around in a in a say Grand View and wind up in our future when you say Grand View you mean a view from outside of those three dimensions you have to be above you have to be above looking down yeah above and beyond that whole set of coordinate

System right uh String Theory you you’ve seen that happen all the time too but imagine kicking a football right a second ago but actually having kicked that football a second ago in one dimension at time but kicking the football five seconds from now in a second dimension of time and kicking it

Uh at the precise moment now in the third dimension of time wait Dimension where is there a dimension where you don’t kick the football not in this configuration that’s that’s called the Charlie Brown demension I forgot about that demension that’s the Charlie Brown Dem so so child

Is it just humans that see time as a straight line and that other other beings in other galaxies are perceiving in a very different manner great question at the moment since we haven’t found other beings in in other dimension or other parts of the universe we don’t know what their brains are

Structured on but the universe as a whole has a causality to it in other words all of the universe as we conceive of it in Einstein’s SpaceTime only has one dimension of time if there are other dimensions of time that we somehow can’t perceive but other creatures can

Perceive and as a result the universe’s causality proceeds differently from what we see then you build up those cool uh science fiction ideas like arrival for example uh which that was the Amy Adams movie few years back I think yeah not the other not the Charlie arrival a few

Decades ago but corre the one where they have the the linguist and the physicist right instead of the astrobiologist and the cryptographer yes that one where where the the premise was if you know your future would you want to experience it anyway right right yeah and the answer is yes I

Want to know my future and then you want to live it I mean even even if you knew all the good and the bad but here’s the thing is you wouldn’t live it no one’s going to live the future that they know but you may you may ultimately cause it

By not living but no one is going to live the future that they already know so that’s problem you’re completely right if time is onedimensional if it is one and if time is two or threedimensional then you don’t know maybe that’s right there you go good question

Okay loved it okay Chuck you got a question yeah here we go this is Morgan Fisher Morgan Fisher says doctors Tyson and Lou it’s Morgan from waterl Ontario of the perimeter Institute the perimeter Institute very nice she says I’ve wondered about this since first hearing of the ligo experiments it is said that

Colliding black holes create ripples in SpaceTime but what’s the medium there’s no air there’s no water it’s a perfect vacuum so what’s actually doing the Rippling and I think she answered the question in the question let me lead off by saying the the perimeter Institute is

A place of study where people are asking questions that kind of sit at the perimeter of of established and accepted thinking in physics math philosophy this sort of thing and so um it’s it’s an audacious construct among institutions that are out there and if there’s any

Weird wild wacky idea that turns out to be true it’s more likely to come from those kinds of think tanks rather than from those in the establishment but so but Charles why you take a gander at this answer well Morgan you have put your finger right on

The concept of the general theory of relativity exactly space itself is a me what Einstein explain EMP space empty space What Einstein explained was that our conception of space being just vacuum or nothingness was incomplete rather we should think of space as this sort of giant uh either a

Rubbery sheet or a flexible sort of Jello-O that we live in that can be bent and twisted and torn and so forth soace jell jell space is a lot like jello Albert Einstein showed that space is a lot like jello you know I mean it’s it’s

A it’s a children’s okay yeah well now what part of the universe has the pineapple chunks in it oh Earth Earth you see the pineapple chunks that sit in your Jello-O mold right some of you may have had that in things and the grapes yeah that that’s the 1960s section of

The of the jell yeah the the the things that are floating in it are indeed Mass uh massive particles and objects or aerations of mass such as planets Stars G and so forth and those blobs cause an irritation to that otherwise beautiful perfect Jello it it it’s an irritant that winds up causing

SpaceTime to curl in upon itself and that’s what gravities it’s the Cur Jello what I like what I like about the jello is you can you can send a ripple from one part of the jello and that Ripple will propagate out as a Jello jiggle that’s right and jiggle its way across

The pineapple Bits And if you’re in the pineapple you’ll feel a little jiggle as as the wave moves across absolutely so good job Morgan you absolutely understand the point that Einstein was trying to make when he developed the general theory relativity yeah but I don’t know if that’s a satisfying answer

To Morgan because what you’re saying is the vacuum is a thing so get over it that’s really I just gave the short version of your answer well I didn’t use get over it I would say I would say Revel in it okay the nothingness is the thing so

Reel in it enjoy make Jiggles in it so that you can send it you know off to the next part of the jello all right okay let’s embrace the nothingness right next up Dennis from Indiana black holes are we sure Hawking radiation is coming from

The inside of the black hole or is it just from around the Event Horizon has an observation ever been made of a black hole dying or disappearing stellam mass or otherwise gentle I’m going to reshape that question and hand it back back over to Charles so we know that Hawking

Radiation is birthed just outside of the Event Horizon we know this okay that’s how the calculations unfold that’s the however somehow that means the mass inside the Event Horizon drops and I want to ask Charles Lou how does the inside of the Event Horizon have any clue what just happened outside

Of the Event Horizon and that’s a that’s a reshaping but a tuning of that question that is a great question and the answer still is we don’t know you see okay next question okay but the idea is that we know mathematically speaking Hawking radiation comes out of any object it

Doesn’t have to be just a black hole it just comes off of any object that has mass except that from a black hole that’s the only thing that can come out of the Event Horizon and that’s sort of the strange part of Hawking radiation it’s not that it uh is unique to black

Holes but we couldn’t measure it if coming off of me for example or of Chuck or or the Caribbean uh as much as we’d like to uh it’s a lovely place to be but it’s very very slow and very very small what happens to create that Hawking radiation is still a mystery Hawking

Himself didn’t understand it now you know Neil right about how people often describe Hawking radiation as maybe like a particle getting close to the event horizon inside and then splitting off production into a particle and anti particle and then the particle escapes the rent Horizon so on so on that is

Pure speculation that works mathematically but physically it has never been sh and it’s actually a little bit problematic theoretically but I’m I’m good with it though I’m I’m I’m I’m good with if hawy said it I’m good well so I mean and first of all it’s you’re talking about

The evaporation of something like the Mojave Desert one half grain of sand at a time that’s right which is which is insane very slow very very very slow very slow but but answer my question if a black hole can evaporate completely how does the inside of the Event Horizon know what

Happened on the outside or is the Event Horizon just a convenience for us to describe the edge but really the black hole and this gravity field the black hole doesn’t maybe maybe doesn’t have an edge that the it’s wherever the gravity field is and the gravity field

Collectively is the black hole and the aing radiation comes out of the gravity field therefore it loses Mass this is another Frontier question a paper was published about 20 years a ago that suggested that mathematically Hawking radiation could be described as Quantum tunnel a a thing where violating what we

Normally think of as the boundaries of Any Given object you can temporarily every once in a while get a little bit of stuff another way to the boundary right and it’s mathematically valid so if it is a Quantum tunneling process then just as you said Neal that it’s get

It’s escaping is a shimmering surface from which things can escape it’s a fuzzy surface that’s right there’s a lot more that needs to be done to going take a minute just to describe quantum mechanical tunneling then we’ll go to the next question right sure so so if

You are if you’re trying to get to some destination in front of you and there’s a hill there you got to climb up the hill and then climb down the other side and that’s a pain in the ass maybe you don’t have the energy to do that so you

Never get there in quantum physics you’re a particle and there’s a barrier there you’re not just a particle you’re also a wave and that wave occupies space and part of your wave exists on the other side of that hill and so there’s a chance you could disappear from where

You are and reappear still within your own wave pattern on the other side of that hill and when that happens it’s called tunneling and it did not actually have to go over the hill and come down the other side to get there and when it happens it happens

Instantaneously it’s not a there’s no time travel for it the the wave for the particle as we say collapses and the particle exists outside of the barrier now does does this remain true even for Jack and Jill particles who went up the hill Jack and Jill didn’t go up the hill

For session pillar water they just Tunnel right through it reared on the other side inside of their own waves who’s next up is it Chuck Gavin Bamber and Gavin Bamber says hello from North Vancouver please visit okay sure and and then he says in lie of a nice question I kneel down and

Ask the follow oh man three puns in a single sentence well done now I really have to go to Vancouver how many black holes are in our uh are there in our galaxy compared to the number of stars is there a fixed ratio or is this just a random ratio so

Yeah well and well we know and do you count the one at the center of our galaxy that’s just one count yeah okay so that does count well this is a great question I’d like to compare our estimates because both Charles and I have extensive research background in

The answer to that question but we might not end up giving the same answer so so Charles let me hear your answer okay here’s my take uh black holes are formed only by the most massive stars dying and so for every massive star that can create a

Black hole at the end of its main sequence lifetime there are millions of other stars that cannot do that so the maximum amount of black hole to regular star ratio is sort of Millions to one but then black holes have now been shown that to it has now been shown thanks to

Ligo and others that black holes can coales and combine and create larger black holes so that total amount can only shrink as you continue to go forward as big stars blow up one in a million or less new black holes can be formed but then as they CES they drop I

Don’t know what the exact mathematical ratio of all that is but I’m guessing that it’s Millions to one or even more rare black holes to regular Stars Neil what’s your take okay I I would say it’s not as rare as you’re suggesting because it’s just a simple um integration of the

Initial Mass function of stars and you just find out the stars that are more massive than eight eight or 10 solar masses whatever the threshold we agree that would be what fraction of all stars in the galaxy have a are born with a mass higher than that I think it’s not

One in a million and the reason why I say that is we have clusters of stars that don’t have a million stars in them but have a high mass star that would die that way maybe a 100,000 stars or 10,000 to 100 so I would say one out of every

100,000 stars in the galaxy objects in Stellar objects in the galaxy is a black hole as the consequence of the death of this process because when stars are made they they’re made in in in in what’s a group of star a pod or should we invent the

Name cluster a a an association CL yeah that’s so boring I wanna I want like a I want a Zoological a litter a litter thank you a litter of stars born out of a gas cloud um we know that the low mass ones many more stars are made that are

Low mass that are high mass it’s rarer and rarer and rarer interestingly if you take a sheet of glass and drop it on the ground and it shatters yeah there will be more small parts than big Parts yes okay a lot of things Land This Way the initial glass function the initial very

Good very good so Charles I’m saying i’ i’ bet it’s more like one in 100,000 not one in million that’s quite a discrepancy between one and a million and one in 100,000 but between astronomers that’s like the same number they don’t care they don’t care you ain’t doing my tax seriously you not

Doing here’s what here’s what I want to know when a when a when a stellar Nursery produces a litter of stars does the Galaxy then Hound the rest of the galaxies to take one of them like hey they’re so chill you’re GNA love it we we just need some Galactic nannies to

Take care of them time yeah okay so do you see my reasoning there I do I I ask them do you take into account very low mass stars and brown dwarfs because if you think a typical Sal Peter initial Mass function right 10 solar masses uh

Every Star that’s 10 times the mass of the Sun there are a hundred or more stars 200 or more stars that are the mass but but those brown dwarfs isn’t another term for brown dwarf a failed star yeah yeah so you or overing planet right right there you go right so stank stank

Oh so what all we’re saying here is that the initial Mass function of stars would include these things that are not stars that would come in even higher numbers than the lowest mass stars right so Charles is just being sort of complete in in the in the mathematics if you’re

Going all the way down to the borderline of brown dwars right then for every Star that can produce a black hole there are millions of objects that cannot objects that’s other objects yeah and the initial Mass function of brown dwarfs appears to be flatter than that of regular stars that

Can have nuclear fusion so yeah okay so Gary both two your taxes coming up okay then you can take the average of our answer then you’ll be bang on I’m sure the IRS are gonna love I was gonna say you could take the average of the answers and you’ll still go to

Jail don’t I’ll I’ll I’ll stick with someone else give me another one okay Cameron Berg says hello Dr Tyson Lou and of course Chuck himself hailing from Salt Lake City and his question is is it possible that what we call matter and energy since the Big Bang have left a

Lasting or ghost effect in the fabric of SpaceTime and dark energy continues to grow because the effect keeps building as matter moves and expands into new space so there we go Cameron Berg’s question is he saying Charles do you think he’s saying that is the is the

Dark matter the absence of the matter that has moved from its location is this um I I feel like if I were to interpret this question more it would be sort of like is the residual effect of the Big Bang what the dark energy is as it fills

Space dark energy or dark matter did they say dark energy he said Dark Energy dark energy right right oh and so I my response to that right Anil you can correct me if you disagree uh the dark energy they’re very sweet a dark energy is has been shown

Clearly not to be the result of matter and energy as we understand it including dark matter all the contents of the universe cannot explain how the universe itself is expanding in a way that is counter to that material so that especially given the fact that dark energy is operating in the opposite

Sense that that energy matter and dark matter would have the universe behave that’s right hard to explain one thing with the other when they are complete opposite in what their forces are right the larger the universe gets the more Dark Energy there has to be in the current

Formulation and that just means that anything that’s left over from what exist exists in the current Universe cannot power that additional Dark Energy creation yeah so deal with it you are you are harsh today I know know I’m getting old and tired and I’m I’m on the porch on my rocking chair you

Know I’m feeling it I’m feeling I’m older than all y’all so I get to behave this way ah all right Chuck what you got all right here we go so this is Emil Forest blood who says Hey Emil from the San Francisco Bay Area wondering about the potential measurement of

Consciousness I believe what we call Consciousness is an energy or Quantum equivalent that emerges grows expands converts like other forms of energy or slash matter it seems that as the universe expands Consciousness is emerging as a natural result of the separation of all matter from its source

Over time we like need something to measure immersing Consciousness if it exists as some fundamental energy what would we use to measure other forms of energy like Consciousness wow honestly your your Consciousness is not your Consciousness right now is electrical wa wait Chuck that’s the wrong that’s the wrong reply it’s what

Are you smoking I don’t know no no no miss that one I got hanging fruit right there like many people agree with your belief believe as you do that Consciousness must be something physical and thing it’s a thing right there is not yet any scientific evidence to confirm that no

If there were some way to measure it we’d be working on it right now in fact come from right there have been studies right there have been studies for example where they tried to measure the mass of a soul or a Consciousness based on uh the mass of your body uh or your

Brain before an event and after an event in terms of Consciousness or unconsciousness and there just hasn’t been anything yet so that said we should consider the possibility the more likely possibility that Consciousness is not an emergent form of new energy but a emergent form of information or organization of well-known existing

Energy that somehow transcends just the motion of photons back and forth in our brains Neil you probably have much more understanding about Consciousness well I like what you said there but I I want to add to it yeah yeah uh something that I think it was Brian Green we were having

Lunch uh couple of months ago and this came up in conversation and it’s stuck with me ever since all right uh you want Consciousness to have some energy field that might be shared among people by the way in physics anytime something happened that we couldn’t explain we investigated it

Found out what caused it exploited it and then ran went to the bank with it so go back in the middle 19th century there’s Faraday who puts a wire through a magnetic field and there’s a meter over on the side connected to that wire and it

Moves and oh how does that hen it’s like what today which seems so trivial back then was an amazing you do this this over here and that happens over there what what what did that and then you find out there’s current there’s something called an electron which

Hadn’t been discovered yet and and every all kinds of discoveries come out of this anytime any of us in the physical sciences confronted something that was behaving in a way that we didn’t know or know the cause of we investigated it okay and so on a tabletop today there’s nothing

Left that is happening where we’re saying we don’t know what’s happening not on a t maybe in a particle accelerator but on a tabletop no your Consciousness counts as a tabletop everybody’s sitting around the table so now here’s the here’s the mind-blowing part when ligo measures the the gravitational wave washing over the

Detector it is measuring the movement it’s it is measuring matter at the level of 120th the diameter of a proton and that is this wave that has moved through the universe for a billion years if there was something going on in the universe affecting matter we would see it in that

Experiment if there was some mysterious other thing oh somebody has a six sense and they have a they have a energy field and they got to it it would show up in those data but it doesn’t so I think we can speak with confidence that there’s not some mysterious mind energy that’s permeating

Space that that science has yet to discover because I tell you I tell you what if it was shaking up that atom we’d have to account for that before we measured the the the gravity AAL wave and that and there was nothing there left to encounter Charles do you know I

Visited the ligo in in in Louisiana wonderful oh what a great facility that must be and and I happened to be there like three weeks before they made the announcement and everybody was like hush liit because they thought I would just run to social media and say no I’m way

More responsible than that but anyhow so so when I watched the kind of stuff that they had to subtract out of their signal what somebody walking yeah on the ground 100 meters away there they are right there yeah a car a mile away yeah um there’s an experiment where they measure

The gravitational constant that’s it’s not ligo another one okay so they got these torsion beams and things measuring which is a very hard thing to measure yeah you realize there’s a mound near that facility where if it had just rained that mound is water logged and

They can detect the extra gravity of the water that’s in the water in the in the in the soil yeah it’s pretty amazing so any that’s my long discussion to say I I I agree with you Charles it’s not a new kind of energy or Force it’s familiar

Energy configuring itself in such a way to give us an a perception of reality that we call Consciousness right so Neil do we measure Consciousness as positive and negative bearing in mind the thought process you have it depends on if you’re into positivity or negativity fig of that haters will be

Haters that’s negative cont yeah all I know is my soul did weigh 21 gr but then I went to Soul cycle and got it down to about eight oh hello all right let’s get our next one up here this is from B BWI and

Yeah n in the south of France in in the Olympics this is a famous Olympic story uh in in 1992 in Barcelona or 96 in Atlanta I can’t remember which one there was a a long-distance Runner named bhaya and he was in this 10,000 meter race and

Two other people uh someone named chileo from Kenya another one named SCA I think from Morocco were lapping him and he you know this bhv was a great Runner he had run a one number of international competitions but he was in the way and you’re supposed to move away as as

Chileo as chileo and SCA were coming toward him SCA was like move move move you know tell tell him take the arm and so he finally moved away and what happened eventually was that SCA won and beat chelo but then the uh event judges the judges of the event took away his

Gold medal because they said that gay had helped him by blocking chileo and it was a it was quite the controversy and then what happened was it was reversed the next day upon appeal but I remember watching that when I was a little kid um watching like that actual event

Happening on the coverage for the Olympics and then showing St being so upset but then Star Episode I have to do this ready Charles why how do you know how you know why do you know that okay so here we go if we imagine a thought experiment where

Two photons of light travel parallel to each other one in the vacuum of space the other in a fluid they both travel at the speed of light and by definition their respective experience of time is zero however their relative speed being different life moves slower in the fluid

They should actually have a different internal clock um how can we make that work as a question or is there a mistake in this experiment great question it happens all the time actually uh and I want you to know that that’s a great thought experiment and it’s actually a physical experiment

That’s been done a bunch of times it it happens when for example subatomic particles enter Earth’s atmosphere there say one subatomic particle misses the atmosphere and heads off into space the other one comes into Earth’s atmosphere and thus is going through the fluid known as the atmosphere right the

Compressible fluid of the gas over its atmosphere just to be clear a fluid doesn’t have to be liquid or wet G if a fluid takes the shape of its container a gas would do that liquid would do that so the whole field fluid dynamics the equations are the same that apply to the

Air or would apply to a liquid because of the Dynamics that goes on for objects moving through it continue Char yes you’re right and so uh we have shown experimentally that the clocks for those sub atomic particles that go through Earth’s atmosphere actually run differently from the ones that are going

Off in space and because of that their Decay patterns are different their half lives are different as measured by us not in the frame of reference of the particle so this is an experiment that has been done and there’s some famous ones uh specifically about a particle uh back then known as

Mumons but you can we don’t still call them that we don’t still call them that we just well usually you just call them muans or maons right oh muans sure sure sorry muon became muan thank you yes that’s right uh so uh you can find these experiments and show that indeed the

Clocks of those individual particles differed from those of uh their companions that did not enter Earth’s atmosphere well by the way the clock um so so just to be clear we’re talking about particles traveling not at the speed of light they have clocks right but if you’re

Actually traveling at the speed of light you would not have a clock and the question was about two photons not about two particles oh well in that case what you do is think about it as having no clocks but through different media and so the speed of light will be different

From one medium compared to the other so you still have the same effect of causality of the surrounding environment having clocks clocking that particle I hope that makes sense I I may not have explained it very well but the idea is that if you’re thinking of time

And measuring time of that Photon which itself experiences zero time the medium still affects the measurement so the so the speed of light is still the speed of light the light is still traveling at the speed of light it’s just that stuff around it is slowing it to less than the

Speed of light lesson the speed of light in vacuum in the right so Charles something I learned recently I never really thought about it yeah that when light slows down in a medium it actually doesn’t slow down what’s what’s happening is it’s still moving at the speed of light between the particles

That it encounters it just keep right yeah yeah and then it has to get through that particle somehow gets absorbed reemitted or whatever if it’s coherent because if the if the glass is translucent then it’s not a straight line through and if it’s opaque it’s not

Getting through it all so the the the the molecules have to be just right so that it is transparent to the photon so it moves through where there’s no particle at the speed of light hits a particle that delays it because you got to come out the other side to continue

At the speed of light isn’t that just what Chuck said it is but I I wasn’t gonna say anything thank you I like I like your explanation Neil I like both explanations they’re I’m I’m exerting positive Consciousness yeah so so the energy of the photon just had to

Get in and out of the atoms or the molecules that were in its way but between them it’s still moving at the speed of like so it’s getting it’s getting refracted it’s getting diverted it’s getting yeah all that can happen and that takes time to get in and around

The particles but that’s the energy moving not a photon as a speed of light moving particle so so the Point Charles is and I like I said I only learned this very much later in life than should have been that photons only ever actually move at the speed of light even through

A medium right I can I kind of see that I can kind that’s really cool so we’ve been luxuriating on so many of these answers and we hardly have any time left oh so give me some good on all right give me some good ones here all right let’s

Get a little personal then this is Mikael bord who says uh um hello Guardians of the Geeks oh there’s AA there’s a t-shirt Guardians of the Geeks Mikel here from Canada who does Charles luk call when he doesn’t have an answer oh no oh no oh well well mik it’s very kind of

You to say that but but obviously uh I know much less than what I don’t know so uh when I need information the first people I go to are obviously you know much less than you don’t know what does that sentence mean it means that what I

Don’t know far out strips exceeds on an infinite level what I actually do know gotcha except what you actually know far exceeds everybody else by an Infinity so so so they don’t even know how to ask you a question your Infinity we’re still embedded in our own Infinity okay dude

Dude that’s too much thank you you’re very kind uh but when I do have a question my go-to people mik are Chuck Nice and Gary o riy oh you you guys may not know this but uh actually actually Gary and Chuck I wanted to ask you if

You had a chance to um take a look at my question that I sent you last week where we would use maybe use the cross terms in Einstein’s field equations to figure out the topological constraints to A W uh many worlds interpretation Quantum Multiverse have you guys figured that

Out yet for me and I I wrote you back and I was like what a dumb question oh I mean you had it right I knew it I mean Gary I don’t know if you had a different opinion on that already no I’m I’m I’m I’m selling that to a really high

Ranking SN tanks at the moment I’m not prepared to discuss it in public well no when when Chuck Nice and Gary O’Reilly do not have a question answered for me right away um I usually go to my brilliant wife Dr Amy Radu and my three kids uh I am blessed to be the

Dumbest person in my family I’m gonna attest to that actually I hung out with this kid yeah um and so I always PhD in mathematics so yes Charles was the dumbest one in the household it is true by far order of magnitude so so Amy and

The kids are are really helpful and I always go to them if I don’t know something and then if we all have to look something up uh I always try to find at least three different sources with three different answers to compare them there’s so much misinformation

Doesn’t have your answer there and right news right really exactly um I always want to be sure there’s so much information out there that I estimate that a third of it is outright wrong and a third of it is sort of right and then the a third of it is probably right so

I’m always trying to find at least three sources of information people that I trust sources that I know I actually go back and read the papers if I can the original sources yeah look at the actual inform real the real question there though Charles yeah because that that

Can be flawed I can look up three different sources and they’re not credible sources so how do you how do you how do you vet your source to make sure that it’s credible that’s what that’s what I know that is a process and sometimes it’s frustrating it takes

Quite a bit of time I will look at the source and then I will look for references to that source and say are those sources reliable or unreliable what have other people said over long periods of time very often if you uh say type A search into any given search

Engine the top 20 answers are all from the same Source but copies of spread out everywhere else you you have to make sure there’s Independence among that’s right so I don’t hesitate to do that it’s a little bit of extra effort sometimes a lot of extra effort to find

The answers but it’s worth it it’s the way that I protect myself from misinformation so Charles is like the credible Hulk who all CLA with research and documented peerreview journals that’s smash CH dismember let’s let’s go jump into the next question and we’ll see because I I

Think you know what it’s a bit of a Hot Topic question having look at it here this is from Jane Von Schilling from Scotsdale Arizona um what are the possibilities of the combination of AI and quantum computers so uh is this does this devolve into another question where is

One more powerful than the other and what they both badass and you put them both together that’s yeah and that’s the and that’s the end of us okay or the beginning no you put it together and that is the end of humanity say goodbye or does is that does that solve let me

Tell you let me tell you what let me tell you what the first uh you know how like the first computers they had well they were numbers but they for they were for calculations but the first thing that came out of computer was hello all right or the first the first from the

Macintosh from the Macintosh hello that was the first thing that came out of the computer the first thing that will come out of a Quantum AI computer will be oh you effed up now didn’t you it could be it could be but I I’ll say this right our understanding of

Intelligence itself May in fact evolve dramatically once we understand how Quantum Computing and artificial intelligence merge it’s really neat right now remember everyone uh Quantum Computing is even in an earlier St age uh in its development than regular Computing was in the era of those first counting machines that you were mention

Chuck we are decades away from being able to do anything like put a quantum computer on your desktop right maybe a century right now the quantum computers are cryogenically cooled they’re the size of a room and they’re only able a big Hardware issue right now not two

Tiny cbits at a time to make the calculations right but those tiny cbits can be extremely powerful not necessarily because a cub is the Quantum Computing version I have made I should have made that clear earlier that’s why I’m that’s why I’m here don’t worry about it keep

Talking no thank you yeah a Quantum bit the Cubit right is a thing that depends on staying coherent with other cubits in order to make its calculations the quantum coherence is extremely fragile it requires temperatures very close to absolute zero almost no noise of any kind electron look at it the wrong way

Much you breathe on it the wrong way oh yeah yeah it’s it’s all gone so it’s really really in its infancy but it shows a great deal of Promise in the sense that when you put in one and one before it puts out two there’s a lot of

Stuff in between which we can’t see and happens almost instantaneously and so is that a a measure of how our own brains work that’s a great question artificial intelligence is attempting it is our current human attempt to use non-quantum classical physics to mimic our brains and our intelligence and our

Consciousness right and we’re seeing that that problem is almost intractable to mimic a human brain uh I I saw a YouTube video on this recently um it is remarkably complicated we know the steps but the hardware is seemingly insurmountable in its difficult so those two things put together might do it but

We still got a long way to go before that actually the INF manable complications of the human mind might not be what you’d want to emulate at all right you want to emulate the parts of the human mind that are capable of good things and right and and accurate things the actual

Human mind it commits violence and War and crime and and genocide and not to mention that just the way that we perceive receive information is a perception we don’t actually view information we perceive information which is a big problem after your senses dealt dealt with it right so

It’s easy to praise the brain because we don’t understand it rather than ask does the brain do things that we don’t need to emulate at all because we can do it better by other means well let’s first understand it figure out what’s actually good and bad and what’s causing them all

All the interconnectedness is and then we can distill the good stuff without worrying that that will accidentally cause the bad stuff to happen and that’s the frontier of Neuroscience but I agree with Chuck maybe AI will figure out how to perfect Quantum Computing and then how to per human being

Together will it not then as it as you say Neil solve its own problems I mean look at it look how long it took us from a computer the size of a room to get to a a smartphone that that that timeing is gone now that won’t that won’t take that

Length of time for it to solve problems that we think are impossible right now the the issue is how we solve the problems put your fing on the head well within lifetimes right well think about this if we put an AI on the problem of solving climate change okay it might be

Able to solve it in a day but how will you solve it by killing every human being so that we don’t have to create any more carbon you don’t want that kind of solution right that’s the simplistic simple mind thing when you’re saying well solve this problem quickly no

That’s evil AI That’s the evil Ai No that’s the AI that doesn’t know the difference between good and evil exactly the immoral AI the the amoral aial so that’s where that Frontier is I believe Neil and Gary and Chuck it’s the issue of trying to make sure that we do

It right and do it safely so that whatever AI doesn’t ignore what we need of it it’s the other way around that we worry about if a human is in charge of AI and Quanto Computing go we tell ourselves right yeah well let’s let’s go with temporarily in charge that’s what

You tell yourself about your cat yeah I’m in charge of my cat yeah I mean yeah never ever ever going to be the case so the thing is someone’s going to have that immoral attitude and steer that intelligence in a certain direction there’s not always going to be captain goodat in charge of

AI imoral believes that they are immoral that’s a whole other challenge that we have there you go this becomes very ethical the winners of Wars are those who write the history books and so that’s how that goes and just to be clear in case people didn’t know you can

Be moral or immoral amoral means you are neither moral nor immoral that’s right um so that’s that’s it it just to be clear people know how we use that term and so chuck if you’re an a-hole either one kind of hole or another right well no if you’re an

A-hole we know exactly what kind of hole you are you know I will wrap up by saying that Neil you actually know this much better than I do um astronomers have been using Ai and machine learning for decades we have no fear of this material we are perfectly understanding that this

Can be used to do great things like help us understand data from Millions ions of stars and galaxies when a single human being could do all that calculation at once so it’s not a matter of being afraid of it or saying oh my gosh we

Have to avoid it or oh my gosh we must exploit it it’s another mystery a puzzle a tool that we can work with and we can learn about and we can sick on our unknowns in this world and if that fails we all die okay that’s there you go oops we’re all gonna

Die well we’ll all die eventually right it’s matter when and how yeah all right guys char Charles it’s always good to have you it is such a pleasure to be here everybody thank you so much for having rejoining us and we know that when we all visit your house we just say

Where’s the dumb one I want to talk to that’s gonna beat you hands down hands down right Gary always good to have you man pleasure my friend and Chuck nice you are in AR Ruba right now say hi to the Caribbean for us all we’ll do all right this has been

Star Talk special edition its own version of cosm quaries a delight in its complexity and its Joy especially brought to us in the guys of Charles W I’m Neil degrass Tyson you’re a personal astrophysicist as always keep looking Up