Is The Future Predetermined By Quantum Mechanics?

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Einstein’s special theory of relativity combines space and time into one dynamic, unified entity - spacetime. But if time is connected to space, could the universe be anything but deterministic? And does that mean that the future is predestined?
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Hosted by Matt O'Dowd
Written by Matt O'Dowd
Graphics by Leonardo Scholzer, Yago Ballarini, & Pedro Osinski
Directed by: Andrew Kornhaber
Camera Operator: Setare Gholipour
Executive Producers: Eric Brown & Andrew Kornhaber
End Credits Music by J.R.S. Schattenberg: / @jrsschattenberg
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[@yvesdoesnotexist]

Out of all the episodes of Space Time, this one is the one that left me feeling like a caveman the most.

[@Biogenesiss]

Time to get augmented.

[@PattyCali]

How this not complicated? Quantum mechanics is known for being complex..

[@IamMrJerrySoFU]

@Jacob Turnbaugh It's like with the cat, but in this case, something can be and not be complicated at the same time by different observers even thought the wave function already collapsed. But don't quote me on that, I found this video complicated. And by complicated I mean not being able to grasp all the information and reasoning as the video plays, not in a way that I would be able to retell it later - I would have to sit on it first and deduce what he said by myself - which is still not calculus, but is doing things, which, by what you wrote, makes it complex. Also your presumption that english somehow makes it not (less) complicated doesn't apply to non native english speakers.

[@JesusFriedChrist]

Grug throw rock. Rock break deterministic wave function. Grug no understand.

[@barrywatts8501]

Lol. You like mammoth?!

[@ilmbrk6570]

"Wubba lubba dub dub" Damn Matt, i'm so sorry to hear this, I hope you feel better in the Future. I know these are tough times but i just want you to know that we will always be here for you :)

[@yuotwob3091]

He'll feel much better if you get in his booth.

[@iAmNothingness]

I bet that's how his brain feels when speaking to stupid humans like us

[@yuotwob3091]

@@iAmNothingness Rick's a compassionate person, the dumb ass have nothing to fear from Rick, or the Universe which is the promised land of the stupid.

[@jasonchastain9826]

I've learned so much from this show. And yet, every time an answer spirals out from an exploded question, two more new questions also are discovered. I love it, thank you for all you do at PBS Space Time.

[@stevewhitt9109]

me too

[@sephirothjc]

I'm learning more and more about this (bit of advice, watch more than one video on the same subject and rewatch videos too) and it is honestly changing the way I understand my own existence more than anything else ever has.

[@DeclanMBrennan]

3:21 "The wave function is real". Actually the wave function is complex. :-)

[@flov74]

Lmao, yes it depends on complex variables indeed.

[@DeclanMBrennan]

@Astute Cingulus Way to kill a joke. :-)

[@VladislavDerbenev]

@@DeclanMBrennan dumb jokes don't deserve a life

[@DeclanMBrennan]

@@VladislavDerbenev I can just see all those poor little jokes shivering away as they are led out one by one to the Guillotine. The blade falls and the crowd roars: "Down with dumb jokes. This is a serious world for serious people".

[@KipIngram]

Heh heh... Too easy... Actually the wave function doesn't *have* to be complex - the use of complex arithmetic there is just a handy way to cram a pair of Hamilton's equations into one equation. Just equate real and imaginary parts and see what you get - it's just an instance of Hamilton's equations for a conjugate pair of variables. Use of complex math was just a "convenience."

[@Stern-warning]

So it doesn’t matter what Lottery numbers I pick as long as I pick them at the right time and have enough orange cats watching me. Got it.

[@cacophony7941]

Welcome to RNG manipulation

[@coffeetalk924]

Lol

[@clemfandango5908]

It’s called The Garfield effect

[@jenniperkins4260]

Hahaha

[@jenniperkins4260]

@@clemfandango5908 haha omg you’re hilarious!!

[@brixen0623]

I love the face he makes when he reads a line that kind of breaks the brain. Like he's trying to keep his head from exploding. It's the best.

[@marcovallejo3]

I find fascinating I believe I can grasp what's going on the last two episodes even though I studied philosophy and not physics. These series are probably the best content now available on KZbin. We are fortunate to live in a time where such quality content is available for "free" (not considering you still have to pay for the internet service most of the time). Thank you very much Dr. O'Dowd, you've become a science heroe for me.

[@lewisleslie2821]

“We’ll have plenty of time for time, another time, on space time.” You’ve gone too far this time!

[@fffUUUUUU]

Never enough

[@jttcosmos]

Also cannot help but notice that very short, slight grin of satisfaction when he delivered the line without messing it up

[@AyaJuni]

He has to much power!

[@dominikbeitat4450]

"Ain't nobody got time for time!"

[@mishael1339]

@@dominikbeitat4450 My time is up, goodnight ya'll

[@crumble2000]

11:46 "There are other interpretations that deserve mention, but [they don't deserve it enough to actually be mentioned]"

[@badlydrawnturtle8484]

They deserve it fine, and pilot wave theory deserved a much deeper dive than the "honorable mention" given. Matt is letting his bias on which interpretations emotionally appeal to him dictate the conversation. It's especially funny when he uses "pilot wave theory is having trouble integrating with special relativity" as the excuse for why he didn't give it more time here, since integration with general relativity is still a problem with the entirety of quantum mechanics, but that hasn't stopped it from being the topic of this video.

[@spinor]

@@badlydrawnturtle8484 you know there's a huge difference between integrating it with special relativity and integrating it with general relativity right?

[@neeneko]

@@badlydrawnturtle8484 As interesting as pilot wave interperation is, it really is way behind the other system in terms of working with special relativity. This can potentially be explained by having fewer people working o it, and could potentially be rectified and catch up, but it means that for the moment it is still stuck in the past and has not been meshed with newer discoveries as the dominant frameworks have.

[@wevedonethisbefore8729]

@@badlydrawnturtle8484 Imagine thinking a hand picked, good looking host is in charge of PBS.

[@513morris]

@@badlydrawnturtle8484 - What evidence do you have that these interpretations "emotionally appeal to him"? That's a strange assertion.

[@dpreetam]

I'm glad I found this episode. Yesterday I had the thought that maybe time has always existed and time just behaves in a way that we really can't perceive like how a 2d being couldn't comprehend 3d and so forth. If all of time and space expanded from a singular point, time could be like a series of snapshots in which we can't perceive the breaks in like a picture book being flipped to make a short animation. Every possibility making up the multiverse. The big bang or great expansion being a multiversal expansion and not just our universe. I'm glad to hear others have thought up similar things.

[@celebratedrazorworks6732]

This is absolutely one of the most interesting segments I have seen. In all of this I really do wonder if there isn't much more "spookiness" going on in how reality unfolds. Things like entanglement, synchronization, vortex math.. Etc. This was an outstanding and intriguing way to weave many other complex systems and theories together. I love that he simply posits on the wonderful possibilities. Well said.

[@ct-hv1uz]

Yeah how do I explain pointless dancing of endless variety I could make in evolutionary or biochemistry or physics terms alone? I feel like our world is wonderful beyond our understanding. It’s awesome! I love living. I love seeing more unfold, I love taking more actions.

[@anarchyantz1564]

Yes, this episode was pre-determined to make my head hurt.

[@crumble2000]

But it was also predetermined to not make your head hurt. You just happen to experience being the version of you that has their head hurt.

[@lordgarion514]

@@crumble2000 That would mean there's a version where the show was predetermined to not be made. I feel sorry for that version of me.

[@anarchyantz1564]

@@lordgarion514 That would truly have been a loss to the cosmos in that version. I normally put these on repeat in the background while I build settlements in Fallout 4 and eventually my brain becomes less like grey goo.

[@i.c.rivera154]

Right there with you. 😂

[@luantuan1653]

I'm in the same universe of the multiverse than you. My head has blown up!

[@AndrewDotsonvideos]

Now I want a country singer to write a song about letting quantum mechanics take the wheel.

[@jean-lucchoiniere5587]

In 100 years the Bible turns out to be a complex analogy for the function of subatomic particle interactions and Jesus is the Higgs Boson.

[@tarubewildin6931]

eat the brown part of this banana first

[@steve1978ger]

@@jean-lucchoiniere5587 - no it doesn't. It's just bronze age myths and a mixed bag of ethics.

[@TheChadPad]

"Physics, take the wheeeel!!!"

[@corwin32]

It’s already been written, you just haven’t experienced that branch yet

[@equious8413]

I've always felt like this waveform collapse is a quantum "tree falling in the forest" and the uncertain fuzziness prior to observation is just another way of saying "we can't be sure, but probability states there should be a noise".

[@OuroborosVengeance]

I have re-seen this several times now. Its so interesting, every time i see it again i go to different places in my mind

[@DrSlipperyFist]

I have PhD in Chemistry and absolutely love this stuff. Having taken quantum physics, as an undergrad and P. Chem as a grad student, much of this content is vaguely "familiar", and in my mind I put it together with everything else floating around in there. What blows my mind (even more than the amazing content) is the mass appeal and genuine interest from non-scientists. This is high level stuff; if I have a PhD and it's only sorta making sense. Kudos to anyone seriously interested in this without the STEM background - I imagine everyone's mind is blown in a different way, based on their background....but everyone's mind is definitely blown by what's being suggested here (and in all these videos).

[@thealifexablecreed9811]

He's basically talking about perspective of the universe from higher Dimensions right? What consciousness would be vs now in 3D. This higher consciousness pattern of selection of possibilities? I don't have PhD in anything. So you think I am close to the jist what he's talking? Looking for affirmations.

[@KipIngram]

I totally agree with you, DrSlipperyFist. I do have a STEM education (PhD in engineering), but I'm not a physicist. I loaded up on math in grad school, because I knew I'd want to learn more as the years went by, and I've hammered away at this stuff for DECADES, and like you say, it only "sort of makes sense." It is indeed heavy duty stuff and my hat is also off to non-stem folk who care enough about it to learn.

[@enigma7791]

Agreed...I am a software engineer and logic is my world. I came here looking for answers after living in a house that had a little girl in that wasn't my child. And yes at first I thought I was working too hard, until my wife and I saw her at exactly the same time. I cannot comprehend scientifically what I saw. Hence I am asking questions now!

[@Sk8OppOsiTe4life]

I don’t think people necessarily need a stem background to grasp some of these concepts though. Yes stem trains and disciplines the brain to identify and comprehend mathematical problems like an artist sees shapes/colours, however what makes someone like Einstein and his body of work so relatable and easy to conceptualise is that he used abstract perspectives and abstract patterns of thought to help provide sense in the nonsensical. In that same manner, I think non stem focused disciplines are able to draw influence or growth (giving them that mind blown feeling) from these similar abstract thoughts. Hence where I feel my understanding of this topic comes from. My own personal ability to explore abstract thoughts beyond what my senses and logical processes can inform and make me aware of.

[@ekothesilent9456]

@@enigma7791 similar experiences here my man.

[@Does_it_come_in_black]

Me: time to go to bed. I need to get up in couple hours for work Also me: Great here we go down the rabbit hole once again

[@ntactime_w3488]

Every time

[@timo4258]

Bruh I'm jealous, I'm too sleepy and super tired after just 2 hours of sleep. My work is in 5.5h

[@Does_it_come_in_black]

@@timo4258 dammm all bad dog

[@andreabelle478]

This is fun!!! Thinking about so many things at once. On one hand your got your pillow on the other your thinking prehaps what this dude is talking about and then you go dreaming pretty neat o.

[@janicepedroli7403]

I just can't tell you how much this presentation has changed my life. It has even started to change personal relationships. Thank you so much.

[@savioartwork]

Janice, this is so interesting. May I ask, how did that work for you ? What changed, and how did it change ?

[@avinashreji60]

Dude don’t change anything, this doesn’t affect anything. Whether everything is deterministic doesn’t change anything about us

[@numinous2506]

I listen to these over and over until I understand them. Thank you for expanding my mind. What a gift that could never be repaid with any crude matter, but I'll chip in some bones when I get paid. You've earned it.

[@Veramocor]

Col. Sandurz: Now. You’re looking at now, sir. Everything that happens now is happening now. Lord Dark Helmet: What happened to then? Col. Sandurz: We passed it. Lord Dark Helmet: When? Col. Sandurz: Just now. We’re in now now. Lord Dark Helmet: Go back to then! Col. Sandurz: When? Lord Dark Helmet: Now! Col. Sandurz: Now? Lord Dark Helmet: Now! Col. Sandurz: I can’t! Lord Dark Helmet: Why? Col. Sandurz: We missed it! Lord Dark Helmet: When? Col. Sandurz: Just now! Lord Dark Helmet: When will then be now? Col. Sandurz: Soon.

[@Llamapuncher]

Goddammit, I read that in George Wyner and Rick Moranis's voice. On that note, looking at the currently low number of thumbs up, maybe we're a little old for many youtuber's to realize Mel Brook's brilliant humor.

[@nameismetatoo4591]

@@Llamapuncher "...they've gone to plaid!"

[@TheGrunt76]

Those instant cassettes are a real breakthrough in home video!

[@timjohnson979]

@@Llamapuncher Mel Brooks?... Just kidding. I am that old.

[@alanfoxman5291]

I remember when he was just a writer on Get Smart. (The original. Not the god awful remake).

[@iheartcornwall]

My two year old watched this with me and was very into all the cats, saying "another cat!" and meowing at each of them.

[@radaro.9682]

My five year old watched it with me. She nods along like "yes, I understand. Tell me more" and I just can't help but laugh.

[@dannydevito7000]

@@radaro.9682 Turns out she's actually a genius the likes of which the world has never seen One day she says "Daddy I made a working model of quantum gravity"

[@radaro.9682]

@@dannydevito7000 Would not put it past her.

[@deriansilva368]

Sometimes I think our physics is just from human perspective and at times is limiting to our overall interpretation of the world. I think an advanced enough society may look at physics outside of their own perceptions which would probably mean they’re beyond war as conflict solution.

[@GeistInTheMachine]

Yup. Precisely. I agree.

[@0ptimal]

This one of the best videos y'all have made.

[@blackbearstudio666]

Is it possible that I live in another branch of reality than my wife? So many times we cannot agree on our common past light cone...

[@megamanx466]

Lol. It's possible I guess, because sometimes I feel that way about my past light cone compared to others. :P

[@danieljensen2626]

No, but human memory is not as good as we think it is. It is possible to "remember" things in detail even though they never happened, or obviously to forget things that did happen.

[@encyclopath]

The future may be predetermined, but not the past, it seems

[@Theraot]

No, you and your wife are tightly coupled.

[@stardolphin2]

@@danieljensen2626 Which is why police detectives still get all the physical evidence they can, no matter *how* many witnesses there were...

[@SteyrR]

One thing is a certainty; I am going to watch this video.

[@morkovija]

as an observer from the past - how did that go? I guess our future was determine from where i'm standing!=)

[@Science__Politics]

@@morkovija he was struck by lighting

[@Dipsomaniac]

At least one version of you will that's for sure.

[@kevin6293]

Maybe you already watched it. 😐

[@encyclopath]

You already will

[@guillaumemaurice3503]

Thank you for sharing this that was very interesting. I enjoyed it.

[@Volamek]

The first 30 seconds of this video just 100% light bulbed the entire previous episode. I'm hooked.

[@MarcdeSaint]

What is predetermined is me watching this every week

[@korpen2858]

True, good one

[@ZomB1986]

Unless, like in my case, some KZbin update disabled the slider for receiving updates about subscribed channels, by itself,, and then me thinking it's just calm on YT because of corona, and then finding out the mount I have to binge watch to catch up.

[@iordannelucas]

The first person to ever ponder predetermination had no say in the matter

[@iJosiah]

Uhhh, English..?

[@0xc0ffea]

That moment when a boltzmann brain is the simplest explanation.

[@WWLinkMasterX]

I mean, is any material model for consciousness distinguishable from a Boltzmann brain?

[@VanBurenOfficial]

In the extreme far future, the same process that will give rise to a boltzmann brain will create the greatest, dankest, fattest, smoothest, most dubealicious blunt the cosmos has ever seen, and I intend to be there to blaze it.

[@lordcirth]

@@WWLinkMasterX Yes. If Boltzmann brains come into existence, the vast majority of them will experience the most likely scenario: only the brain existing, and for only a short span of time. Since we see a massive, coherent universe around us that seems capable of creating us, we are either in one of the most unlikely Boltzmann brain scenarios of all - or we aren't one, which makes much more sense.

[@WWLinkMasterX]

@@lordcirth Fair, but that isn't a distinguishing argument, it's an argument from likelihood.

[@Beastman5K]

@@VanBurenOfficial MY DUDE

[@chrismcgarry3160]

6:47 This concept of "Relative Present" just makes "Many Worlds" way more intuitive than "Copenhagen".

[@didack1419]

Isn't the reason Copenhagen is the most popular just that is the least committed to unintuitive theses? I've even heard people saying that Copenhagen is just taken as a purely formalist interpretation, with no actual meaning in which you ought to not ask what "collapse of wave function" means. And, apparently, if taken literally (its physical meaning), the measure device becomes an entity with non-reductive properties, but physics always assumes as a tenet that any non-fundamental entity is reducible to more fundamental entities, so there is a contradiction. In principle, an entity with non-reducible properties could exist, although it makes sense to doubt it given our overwhelming experience that entities seem to be reducible. Other problem that I imagine this has is that there's no defined non-arbitrary boundary between what counts as a measurer and what doesn't. I know I'm rambling by now, sorry.

[@chrismcgarry3160]

@@didack1419 Haha! I wasn't expecting such a fleshed-out response to my "Mental Note". Most of your points make sense, but my problem with "Copenhagen" here is that parts of our future light-cone may be in another observer's present, meaning that any Wave-Function in our Future should have already been collapsed! Whereas "Many Worlds" suggests we still get to "choose" among all the possible branches.

[@nhannhan4406]

I need CC english subtitle in this video, really like all your video. I've learnt so much about our universe in your channel. Thank you.

[@philochristos]

"We'll have plenty of time for time next time on Spacetime." That's just brilliant writing right there.

[@iamchillydogg]

Thanks for ruining it for the rest of us.

[@Gamer-is6ew]

@@iamchillydogg Why read the comments first place then before watching the intire video throughout? It is you responsibility since you're already agreeing non-verbally to that - when you open that comment section your bound to be exposed to spoilers...

[@iamchillydogg]

@@Gamer-is6ew Your comment is the one that shows up before you open the comments section.

[@Gamer-is6ew]

@@iamchillydogg time to burn down YT's HQ for this!

[@SpeedOfTheEarth]

"But - we'll have plenty of time for time some other time in spacetime." Brilliant lol

[@internet_introvert]

Time? This isn't the time to talk about time. We don't have the time!

[@platypuspracticus2]

Love how this kinda glosses over the fact that a conscious observer collapse would imply a very high significance of our existence given that not everything can cause that collapse. Not quite deific but not far off given a direct impact on the shape of reality itself. Also probably why a deterministic multiversal solution feels the most right: clearly we're not gods. Despite what some people may think.

[@schmetterling4477]

Some folks just can't pass a heap of bullshit without diving into it. ;-)

[@PlayedbyInstinct]

Remove 'conscious observer', insert 'frame of reference', of which some include a conscious observer. Still deterministic, just dependent on your frame of reference (you don't cause the collapse, you observe it).

[@Wulable]

"We'll have plenty of time for time another time on space time." Haha great.

[@ilkoderez601]

This is a great episode! This is the stuff that keeps us coming back. I've been interpreting the multi-worlds theory all wrong and it's not my fav... Thanks PBS SpaceTime! Bravo!

[@Iangenker2]

What is mind? Doesn't matter. What is matter? Never mind. - Homer Simpson.

[@worldshaper1723]

That's a great joke!

[@simoncollins69]

this used to get stuck in my head as i walked to school.

[@elliotnicklinmusic]

The intersection of the conscious experience of a single branch with these interpretations is so alluring, as is the romantic notion of altered states of consciousness (like dreams) being an experience of these other possibilities.

[@monsterlair]

“We’ll have plenty more time for time, another time, on space time.” Best valediction yet. 😆

[@azure6743]

"Einstein's theory of special relativity combined space and time into one unified thing - spacetime" *show ends after 9 seconds*

[@AbbeyRoadkill1]

When I saw the notification for a new Space Time video I knew I was going to have to click on it, so... yes, the future is predetermined.

[@dwighthawkins5955]

I seriously need a revitalized definition of "predetermined" as there was no way I could watch this video without toweling off first.

[@tiantu9830]

My problem with non-deterministic idea of these "unknown" qunatum probabilities, is that it is still ultimately deterministic. Think about it, if you are reading a book series and it is unfinished. From the perspective of the characters in the books, yes, the future is unknowable, but that does not mean the characters in the book get to influence the outcome of their future. All it means is that whatever force(in this case the author) that drives the future, has not made a determination yet. But that does not make the book itself non-deterministic.

[@s.31.l50]

The book analogy is one of my go-to analogies for determinism, happy to see someone else with the same idea.

[@johanneskrv]

So you're basically smuggling god into this by assuming an author. What if there is no book at all? What if there is no all seeing point of view?

[@typhoonf6]

@@johanneskrv he said a force... It does not have to be a deity. Could be probability or some other level of physics we don't know about. You are the one that made the assumption.

[@Zargabaath]

@@johanneskrv The author could just be time, or whatever determines, well, determinism. You made a leap, and an illogical one. Why would someone who thinks determinism is the answer believe in a god? Especially the christian god, which I'm assuming is the main deity you're surrounded by, seeing as christianity is all about free will.

[@johanneskrv]

@@Zargabaath No i didn't make any leap. The reason is the following: in all these models an all seeing point of view is assumed from which the block universe (time+space) can be examined. From this point of view of course everything in the block universe is always deterministic. But assuming the possibility of this point of view means assuming something outside the universe. Colorfully stated this means assuming god.

[@XIIchiron78]

Doesn't the speed of light + relativity of simultaneity "fix" the 2nd example? Observers in your "present" can't gain any information that isn't within their light cone and therefore can't collapse your future wave function by learning about it from an observer in your future path. Or do I misunderstand?

[@loturzelrestaurant]

I have the (silly) hobby to ask people if they'd like some recommendations; especially science-channel and such. Yeah, its random and i'm often called Robot for it, but who cares? I live for those few who say 'Yes thanks' (though No thanks is also nicer than calling me non-alive...) and i wont stop asking around. I wanna spread Education, so i recommend edu-channel, duh!

[@yuvalne]

"We'll have time for time another time on spacetime." Goddamnit Matt.

[@Robert_McGarry_Poems]

The time to discuss endless time has passed, this time. But, maybe next time, on spacetime.

[@Wetefah]

"the answer depends on your favorite flavor of interpretation" - I'll interpret this as "nobody has the slightest idea"

[@MarsJenkar]

I'd say more like, "We've got a few ideas about this, but we're still trying to puzzle out which, if any, is right."

[@badlydrawnturtle8484]

It's more like "the interpretations that make more sense logically are less appealing emotionally, so we like to downplay the part where we're supposed to find the truth, here".

[@maythesciencebewithyou]

Many people desperately want to believe that the universe is not deterministic or at least that there is a version of them that lives the life they dreamed about.

[@alram8143]

@@badlydrawnturtle8484 cynicism is also emotional. It also doesn't advance scientific discussion. Saying "we don't know" is not a failing.

[@paulperkins1615]

There is a huge range in between "the exact answer is known beyond any doubt" and "nobody has the slightest idea" and I don't think I really like anybody who is not comfortable living in that in-between range.

[@janicepedroli7403]

Love this video. Changed my life and the way I relate to my grown children. Now there are many free will choices they can make. They create the choices.

[@MrSperoni]

The cat explanation was just brilliant.

[@JanKowalski-wb2fv]

If the future means watching PBS Space Time then yes, it's predetermined

[@RagaarAshnod]

For me, it was reading and replying to this comment!

[@syngyne]

Also predetermined that I will only ever understand about 2% of any one video

[@NicholasRehm]

I watched Interstellar (again) the other day which really messed up my mind and got me thinking about the idea of a pre-determined future...

[@anarchyantz1564]

Watch it a third time sort of in the background while doing other stuff. Hurts your head less I found.

[@SeanONilbud]

The lesson is books cause hurricanes.

[@biblebot3947]

Watch Sabine hossenfelders video in it

[@NicholasRehm]

@Deal Negrasse Bison My guess is you think you're too smart to enjoy it, right?

[@okkomp]

The illusion of free will evaporated for me in 1997

[@tavishubbard6731]

I just read a book trilogy called, "The Three Body Problem." Highly recommend this book! It plays with multiple topics that this show is famous for. Also an episode about the sciences involved in the books would be epic!!

[@nostalgia63]

Nice video. Philochrony is the theory that describes the nature of time and demonstrates its existence. Time is magnitive: objective, Imperceptible (intervals) and measurable.

[@_shadow_1]

"The only thing that is certain is uncertainty" - Probably someone in history

[@arielsproul8811]

You could say that you're *Uncertain* as to who said that quote

[@Mp57navy]

I'll go with Feynman. Any takers?

[@rmsgrey]

"With him around, even uncertainty is uncertain" - Interesting Times by Terry Pratchett, Death(?) speaking of the great "wizzard" Rincewind (luckiest(?) person alive)

[@_shadow_1]

@@arielsproul8811 yep

[@philochristos]

I wonder how certain they were of that.

[@mstandenberg1421]

The universe is infinitely predetermined, which is to say finitely unknowable, thus it makes no difference unless you’re outside it in something bigger and stranger.

[@hillarysemails1615]

I was only the 7th Like and this is over a year old? Shame people. This deserved over 100!! This comment should have been in the vid. "An Infinite series of predetermined universes, means a pseudorandom experience for any given observer."

[@christiangonzalez7438]

Im taking this as an universal wisdom quote.

[@johnwoodhouse2360]

Very well explained. Have wondered if them life moments when feeling uncomfortable with life direction could be anything to do with a gravity pull to your timeline but am understanding much clearer now that this concept is probably unlikely because every possiblity is happening but we are only experiencing one path of time but this leads me to another thought. If as 3d beings we can see everything in a 2d world. Does that mean they might be 4d beings that can see everything fully in our 3d world and is 4d time? One more things if time travel was possible going to the past would be going back on time line you have taken but how would going to future be decided what timeline it too when every possiblity is happening? Just some thoughts. All the best all.

[@gbail9566]

Congratulations on the wonderful graphics on the Copenhagen and Many Worlds theories.

[@petersontaylor2000]

Matt asked for our help at the end of this episode! Hang on in there, my friend! Everything is gonna be fine!

[@chillyman1459]

What is the difference between an observer and just any old regular particle interaction? If an observer is just made of particles, and the particles the observer uses to interact are doing the observing, wouldn't that mean every particle interaction collapses the wavefunction?

[@markiv2942]

Yes, don't just tell this to anyone, it would make too much sense.

[@zeton2000]

yes

[@db7213]

In the many worlds interpretation, different observers have different wave functions for the same particle. So even all particles are observes and collapse the wave function, their interactions don't collapse the wave function for other observers (unless the observers are entangled). Example: we have particles A, B, C and D. When particle A interacts with B, A's wavefunction of B, and B's wavefunction of A collapse (and A and B become entangled which means they now share wave functions), but C and D's wave functions of A and B are unaffected. When C and D interacts with each other, their wave function collapses and they become entangled. When A or B comes in contact with either C or D, then A/B's wave function of C/D collapses and vice versa, and all particles are entangled. So as you can see, the wave function collapse becomes a chain reaction (which is what causes the many worlds).

[@badlydrawnturtle8484]

You've just intuited the fundamental problem with the Copenhagen interpterion, which despite having this obvious issue has managed to keep going for ages because even physicists get emotionally attached.

[@mertertrern]

Gotta remember the part about there necessarily being only a single observer in the entire Universe in order for the interpretation to work. I'm not landing on either side of that question, but I wanna imagine that self-aware consciousness has some privileged position in the pecking order of wave function collapsing. It's possible we're collapsing this sea of quantum possibility into the manifest reality we perceive in real-time through unconscious processes we haven't even begun to uncover yet. You never know. New ideas are usually considered wrong by a lot of respectable scholars until some new discovery comes from out of nowhere that changes the tide.

[@nyrdybyrd1702]

My first watch of this episode (years ago) went swimmingly but I've been around since the days of Gabe (seen erry episode, most several times). I sympathize/know the feeling though; the most difficult concept/topic covered here for me was (without doubt) time crystals (pretty much baffled to this day 🤷‍♂️).

[@winstonsmith8240]

Glad we've cleared that up.

[@dominikbeitat4450]

Not gonna lie, this is the best explanation of 2020 I've come across so far. Something something collapsing future something.

[@bigchungusdriplord2301]

Nice

[@scottjohnstone6204]

Something something corrupted and bribed and blackmailed governments and institutions.

[@p1a2b3l4o50000]

This is the better “science of Dark explained” video I’ve ever seen

[@aimefortunato3334]

Mind blowing!!!!! Great vid

[@markl3763]

Hi Dr. O'Dowd. 2 questions: wave function collapse seems to require observation, which to me seems to require life, so what if life never evolved? and if time causes gravity, and time is money, does money cause gravity?

[@_tnk_]

Love the focus on metaphysics and philosophy these past 2 episodes. These are really difficult concepts to understand, and I appreciate seeing your perspective as a physicist. Question: What do you think about the “moving spotlight theory” of time as an explanation for the experience of the present?

[@MichiganUSASingaporeSEAsia]

I see the point of the spot light theory

[@shamashmindful]

You've literally put him on the spot

[@erikzetterberg3887]

Thanks to Matt and the PBS space time team for making these great videos! This time, however I find the argument at 6:50 unconvincing. The claim that the event at the bird would collapse the future of the event at the human does not seem to me to be supported within SR. Just because the human sees the cat event as simultaneous and the cat sees the bird event as simultaneous does not imply that any of the observers see the human event and the bird event as simultanous. Actually, the human, the cat and the bird would all agree that the bird event happens after the human event, and because of this the bird event could not collapse the human's light cone. In fact, there could be no observer moving at the speed of light or slower that would see the bird event as simultaneous with the human event, since these events are time like separated. The human's event and the human's future would remain uncollapsed from any observers view. At least as far as I understand SR. Please comment if there is anything wrong with my line of reasoning, so that I could understand the argument in the video,

[@davidpalmer9780]

What blows my mind is the tracking of all the alternate realities prior to the wave function collapse, if it even being tracked at all. What I consider tracking may be considered something else.

[@ride14fun]

this is the BEST, I think, MOST accurate description of reality. FURTHER evidence is that it supports the axiom of choice from Zermelo Frankel set theory which is critical to generate modern mathematics.

[@Richard-bq3ni]

I am currently picking up the pieces of my brain shattered through my room after my head exploded. Why do I always feel dumb watching your videos. I have a hard time understanding but keep coming back still.

[@goldenseal50]

So glad I am not the only one with a headache.

[@philb.1658]

I agree I too find these videos hard to understand and but they are interesting and informative. My brain only feel like exploding when I watch crap on TV about ancien aliens or ghosts.

[@Richard-bq3ni]

@@philb.1658 Hi Phil. Thanks for that, I feel less stupid now 😉 And I get what you mean with these TV shows. Channels like discovery were great to watch when I was young, but have been dumbed down to please a larger audience, or whatever the owners had in mind. It is great to have KZbin and channels like this.

[@ytechnology]

"... but keep coming back still." It's disturbing that your return visits might be predetermined. 😉

[@rilist23]

Yes..right there with y’all on that thought lol

[@RussellCatchpole]

The wave function probably collapsed, just in time, for Matt to deliver his final line, in a rhyme, before the final chime, of this episode of, PBS Spacetime.

[@King-jx3kx]

scientist: "discovers entanglement" Will Smith's wife: I cheated because of entanglement. It's predetermined.

[@LieutenantStandby]

When I'm unbanned on facebook, your comment is the first thing I will post and I'm going to quote you with this video.

[@mvtito2711]

I'm sorry I laughed at will smith's wife

[@rajatchandra3209]

😂😂😂

[@eprofessio]

Is that why will smith hates white people? Asking for a friend.

[@mvtito2711]

@@eprofessio lmao that's not true

[@PromethorYT]

Random thought: so if entangled particules are separated one at rest and the other moving near the speed of light and we measure the particule that is at rest, it does it means we affect the state of the moving particule in the past?

[@tellmemoreplease9231]

To me, that sounds like a very good question.....

[@flumbz5266]

You mean like the double slit experiment?

[@queenofscots839]

I spoke to my future self at age 7, and answered 40 years later ... remembered exactly on time! 🤯

[@MrBruh-xc1qy]

this is legit one of the most epic comments i have ever read

[@richardkoechl9552]

@@MrBruh-xc1qy are you allowed to change your mind in the interim???LOL

[@Imachef]

What did you tell yourself?

[@queenofscots839]

@@Imachef I had a nightmare that my younger sister surprised me with skydiving gift and I’m terrified of heights, I begged my older self to say no! So when 30 years later she did just that I apologized to my younger self and went!

[@cherubin7th]

What if we do the same but instead of "now" to slice the block universe, we use the path light cone as reality and as soon as they leave the cone they don't exist anymore or they exists but at an undefined time (but all observers are still equally valid)?

[@nofatchxplzthx]

This has always been in the back of my head since i was a wee lad

[@venataciamoon2789]

Since I was 9 years old I knew my future was not good and 41 years later I was right. I looked a fortune teller in the eyes at 21 and knew right there what she saw. She lied to me telling me a load of stuff that never came true. Why don't they tell you the truth that my life from there would be bad. So I've always thought the future was written.

[@ghytd766]

Love this stuff. I wonder if my future self understands it.

[@Alverant]

I liked it when we see the "third" guy laugh at the cat doing something cute.

[@theonetruemorty4078]

It's me, I'm the one collapsing the wave function. I know I've made mistakes, especially as of late, but if you cancel me you do so at your own risk. Cheers!

[@cezarcatalin1406]

Yeah it’s big brain time.

[@nunyobidniz]

I squanch it😎

[@chrisfinley]

Does it have to be one person or can a solar system bound species be the one collapsing the wave function? That would explain the Fermi Paradox and probably means we are a simulation. ;)

[@big_changus4905]

Does your momma know you do this, aren't you a little young to do this

[@subwoofer6238]

Very cool! and when learning this it feels very... comforting? Knowing that nothing is classical mechanics really happens randomly and everything has an effect on something else. If you choose to fly a plane, there are soo many things that that effected (That will spread out across the universe through entropy over time and create more causal chains) and all the things those causal chains that caused to make that decision. This is definitely something I would geek-out on lol. I also realized that even if the universe is deterministic nothing in the universe could ever predict it. (Which is probably the reason WHY we can't prove anything about how the universe operates) This is the same thing as the "Halting problem" where you can't make a machine that simulates and PREDICTS another one aka. The universe. This is why none of this actually matters you or any object or atom or molecule in universe because you can't change it, it's always BEEN the universe, and this is a better way to create a universe that FUNCTIONS then having things happen randomly that can actually effect you. (Like changing you're decisions or some stupid stuff like that). Because if randomness has an effect over only you're brain than why? Why can't atoms of your arm or any object float away and make everything into gas or clumps. To people who feel nervous or "trapped" by this I want to tell you that it doesn't matter, nothing can predict the future, and it's still okay to think about this though because we're just speculating and trying to change your future or gain free will doesn't mean anything. The universe is ordered and that's how it exists in the first place.

[@hdbgdz]

I want a tee shirt that says "The wave function is real"

[@nathanielhunter1280]

Or "I just collapsed your wave function"

[@waffles3987]

Bump

[@paulperkins1615]

@@nathanielhunter1280 I like "We just entangled parts of our wave functions with each other" even better. But "The Wave function is real" fits on a tee shirt better and captures the essence of what is usually called the many-worlds interpretation.

[@thedeemon]

"...but unobservable"

[@pierreabbat6157]

Is it real or complex?

[@adrismith3134]

This is slicing through the layers of my brain.. I need to listen to more so I can figure out how I managed to time travel to my own past and give myself advice.. I know I've done it in the future from meeting myself in my past.. But this time is the time to give myself the answer to Save myself time.. So now that I've found this maybe I'll figure it all out in time... Thank you for your time and this....

[@dynasticlight8706]

Isn't it ,the older We get life is seen or understood more clearly .We seem to live backwards w/ more understanding .Maybe ,not being able to use it now as We could have then.

[@andreabelle478]

Wow you have a very interesting matter of thinking and reading this helps make sense of all this. Thank you.

[@Feintgames]

Other required listening is, "Story of your life" by Ted Chiang. It has the best explanation of experiencing "present" as a being that doesn't need to limit itself to existing between past and future. And if we can imagine and calculate these 5th dimensional beings, who is to say that our interpretation of existence defines it?

[@parthsarda2793]

It seems valid to think that we are constantly changing realities with respect to change in condition

[@livedadyt10]

Phew... heady stuff Matt. Still struggling with “if a tree falls in the forest...”.

[@itcamefromthedeep]

I can clear up "if a tree falls in the forest...” if you'd like. We use the same word for two concepts, in this case one of those concepts is vibrations in the air, while the other is the subjective qualia of mental experience. The falling tree definitely makes sound in the first sense, and definitely not in the second. The confusion lies in the ambiguity of the word, not the concepts it points at. If you were to try it in some other languages it probably wouldn't work unless they shared the same homonym.

[@johndoe-sh8in]

If a tree falls in the forest and nobody is able to hear it... then my illegal logging business is a success.

[@GawerLT]

@@itcamefromthedeep Exactly right! Funny how people don't examine this and think it is profound :D

[@ultratot]

@@itcamefromthedeep Yeah... but... if you ascribe any level of consciousness to animals, squirrels and deer and such, then the subjective mental experience, that qualia (maybe my new favorite word since the last exurb1a video?) definitely is there. So in both definitions, objective vibrations and subjective experience, the answer is an unambiguous YES. So now that that's cleared up, onto determinism and the hard problem of consciousness...

[@Pheonix1328]

I'd say it doesn't make a sound, at least in any meaningful way. Observers are needed to allow things to exist, for if there were none, then it would be like it didn't exist at all.

[@CanisSubwoofus]

I thoroughly enjoy the fact they went through the trouble of adding "meows" to the cats.

[@linux1800]

Hahaha

[@matthewabln6989]

The subtle touches.

[@marcelolibermandeloreto5252]

LMAO

[@jfjkdkjfj]

Cats come with meows automaticly. Its the most certain thing in the universe.

[@Cheekymukka]

Great topic I really enjoyed the video. I have a view as follows: I believe past, present and future are viewable to souls not in an avatar. How this is possible is explained as follows: The past present and future of a soul in an avatar CAN be simultaneously viewed as if you where standing over a merry go round. The merry go round is the complete life cycle of the souls present life and it's future events can be accurately determined because of the uniqueness of the soul to choices it will face in life. The probable paths it will choose even though it has free will to do as it wishes, it is very very likely to be only choice A or B out instead of a cone of infinite 180 degrees of choice as illustrated in the quantum observer in your video. I believe a soul is very likely made of dark matter and the universe it returns to is completely hidden to avatars made of matter unless they have the unique gift some humans appear to have down the centuries of past. Ultimately, we are here to learn no MATTER (pun intended) where we are in the 4% of this cosmos and the lessons get tougher the wiser we become as souls.

[@winfredbe]

“Probability wave”, “Wave function collapsing”... I call it magic.

[@StsFiveOneLima]

Yeah, people used to say that about fire and lightning, too :-)

[@kena7007]

I love listening to this show, I memorize a few quotes and say them at dinner and people think I’m a genius.

[@dadk5470]

Lol

[@omaewamoshindeiru3657]

You just made me questions my existence and reality

[@Matty94]

Try to watch Pursuit of wonder

[@TheChadPad]

Great way to start the day

[@ankysid8022]

What do you think Physicist do ?

[@kaseyboles30]

Always question and seek answers.

[@playnite2188]

You exist so I can reply your comment.

[@schumachersbatman5094]

best episode yet

[@chuck762]

Good looks on the existential dread bro

[@AdamAlbilya1]

16:10 I feel you brother, this year was harsh indeed for everyone. How can I help?

[@maythesciencebewithyou]

send cookies

[@AdamAlbilya1]

@@maythesciencebewithyou Some Eyeholes snacks might be better perhaps

[@nUrnxvmhTEuU]

You forgot to mention Carlo Rovelli's relational QM interpretation! My favourite interpretation, where even the very collapse of a wavefunction is relative to the observer. I feel like it would be relevant here.

[@valkyrie321]

Now that offers some intriguing questions of its own. If that’s true, than I take it that every observation is only relative to the observer itself... And thus it’s a flavor of the many worlds interpretation? So as I’m cutting my way through space-time, the collapse of the waveform is unique to me only... Oof.

[@diribigal]

Yeah! I like it more than the interpretations mentioned in this video, and it seems like it might mesh with relatively more easily, as you said.

[@nUrnxvmhTEuU]

@Jaggyroad Yes, you are right, technically it is a flavour of Many-worlds, but it doesn't need the concept of a "global wave function". But philosophically it is quite different, and I would argue that it gives the same results using fewer assumptions.

[@thedeemon]

@@nUrnxvmhTEuU I wonder how an interpretation can have fewer assumptions than MWI. MWI just says "take wavefunction and its evolution equations literally", no more assumptions, no collapse, no special role of observer, no classic-quantum distinction etc. Gotta read about the relational one, I'm not familiar with it.

[@davidhand9721]

This is one of my biggest problems with the fundamental randomness of QM. We know for certain that one observer can see another's future in its present, so it can't be undetermined in the other observer's present. It's a direct contradiction. We need a better explanation for how realities are selected from a set of potentialities, one that explains consistency between observers. That means we need a better explanation for what happens during a measurement and "wave function collapse". But it seems these questions are prohibited among physicists, who have taken "shut up and calculate" to heart as dogma.

[@TheMrMxyspptlk]

Outstanding!

[@monochr0mat]

I was thinking about this a couple of days ago. If you consider the universe as a graph with nodes being Quantum states. You are a DFS algorithm through this graph looking for your death 🤯

[@big_changus4905]

My computer friend

[@kingreinhold9905]

Can you please explain this a bit more?

[@ConnoisseurOfExistence]

I'm a special algorithm, looking how to avoid death and survive forever.

[@ethanconnelly8794]

Maybe our qualitative experience (qualia) exists in the momentary entanglement of ourselves and the world. This would mean any other conscious entity who wants to see the colours of our soul would have to entangle with our wavefunction or collapse it and just see quantitative data. With pansychism this means that everything that is still in it's quantum state would experience it's own qualia and only under a non-zero like cooperation would it be able to join another conscious entity and create higher orders of autopoiesis. The sharing of electrons is simply the sharing of consciousness. Higher complexity leads to higher states of consciousness and therefore the most complex systems (our brains) are experiencing the highest levels of qualia.

[@kallianpublico7517]

An algorithm is a sequence. Is my sequence the same as yours? Not if my definitions are distinct, unrelated, to yours. If I have words, thoughts, which are "more advanced" than yours then the set of rules that leads from proposition to conclusion, from if to then, will be different in number and in "meaning". Is meaning the source of the quantum enigma?

[@Trekfolie]

I'm happy for the countless other me-s who lives in world where 2020 is a nice year

[@zhangalex734]

We could be wiped out by quantum Darwinism :(

[@megamanx466]

@@zhangalex734 Or a quasar shining our way... OR... OR... :P

[@WaveOfDestiny]

There's also one where 2020 is even worse wich is scary

[@megamanx466]

Or where neither of us exist. :P

[@sevens3]

@5:30 Yeah but what's the mechanism for us being the us in THAT branch, and not the others? Seems like (as I'd maybe expect) a restatement of the same exact measurement problem/wavefunction collapse in it's practical effect (we observe a particular outcome, we presume other outcomes were hypothetically possible) as is in Copenhagen.

[@ishanychheda1725]

Very well explained.

[@shelburn1489]

Thank you so much for the great content. I absolutely love this channel!