55 | A Conversation with Rob Reid on Quantum Mechanics and Many Worlds

Blog post with audio player, show notes, and transcript: www.preposterousuniverse.com/...
Patreon: / seanmcarroll
As you may have heard, I have a new book coming out in September, Something Deeply Hidden: Quantum Worlds and the Emergence of Spacetime. To celebrate, we’re going to have more than the usual number of podcasts about quantum mechanics over the next couple of months. Today is an experimental flipped podcast, in which I’m being interviewed by Rob Reid. Rob is the host of the After On podcast, of which this is also an episode. We talk about quantum mechanics generally and my favorite Many-Worlds approach in particular, homing in on the motivation for believing in all those worlds and the potential puzzles that this perspective raises.

[@WeeWeeJumbo]

I will never get tired of this particular discussion topic.

[@TheReferrer72]

I do don't understand it at all.

[@svenjaaunes2507]

i almost memorized Sean's speech for the many-worlds interpretation

[@jonjay3782]

@@svenjaaunes2507 onopmo i oni I

[@moonhouse3540]

I'm very grateful to have evolved along the same branch of the wavefunction of the universe as this version of Sean Carroll.

[@StatusQuo209]

Rob is such a great speaker. Very articulate. It's always a great show when you have two great speakers on a podcast. Bravo!

[@gezakisch4730]

l?o

[@wasp89898989]

Absolutely LOVED this episode Sean. Please please please have further discussions on Quantum immortality, Many Worlds, and all the rest!

[@madderhat5852]

A great discussion of one of sciences' great shames. Never should you stop asking questions.

[@dr_shrinker]

30:09 like a photo of a flying baseball. If it’s clear, you can tell the position but not velocity or trajectory. If it’s blurry, you could tell the trajectory and velocity, but its position is uncertain. You’re welcome for this analogy. Love your work Sean!!

[@hughJ]

Only part way into this podcast, but so far this is one of the most impressive examples of a cooperative/complimentary conversation where the cadence of tandem explanations -> rephrased explanations go back and forth without any disruption to the train of thought. Normally this dynamic is prone to disruptions where the original speaker is forced to explain how the rephrased explanation is invalid (often leading to a tangent) and then recover to reword their original point. This almost has the cadence of a faux-conversation from an infomercial.

[@yorshka6955]

Please keep up those great quests and topics!

[@yorkshiretoffees]

I like this style of Mindscape more and the interaction between the two of you makes it much easier to take in the information.

[@shmookins]

What a wonderful discussion, thank you. You have the best podcast!

[@christophergreenDP]

Niven, Larry; "For a Foggy Night," 1971 (...and, thank you Sean (and Rob)! Excellent work as usual :)

[@82spiders]

Thanks. Niven is under appreciated.

[@markrich9600]

I'm very thankful for your explanation. It had been just in time.

New podcast.... it's a good day🤙

[@jeffreyblue627]

Reid is a marvelous interviewer.

[@publiusrunesteffensen5276]

I keep coming back to this episode of Mindscape.

[@owaisahmad7841]

Rob is a great podcast host and Sean Carrol is one of the best physics communicators. What a show. Thoroughly enlightening. Need more programs covering other topics of interest like time or cosmology etc involving Sean and Rob together in a podcast!

[@jessemontano6399]

Sean's podcast is of such high quality content and speakers it will have 1 mil subscribers before we know it. I congratulate Sean in advance !!! Bravo!!!!!

[@MrJimbissle]

Every time I take in a discussion like this, I find questions and/or answers to old ones. Without actually being a student Im starting to get the maths under some growing bit. I notice that hearing someone at this level express some idea I have toyed with is both exhilarating and humbling. Refining the whole mess is great fun. So long as I dont fall through some wrong looking glass . . . for too long. Thank You Both.

[@MrJimbissle]

@@lepidoptera9337 You just might be surprised. At the very least I understand that I can be a great student given the opportunity. And that arrogance is a self inflicted handicap .

[@adamdalgleish8769]

Love this topic

[@hughJ]

Has Sean ever spoken about the delayed-choice quantum eraser experiment? I would like to hear him dig into what it is (or isn't) and how that behavior is described by different QM interpretations? Reading about the experiment makes it sound incredibly significant, but it seems to never be referenced as an addendum to the vanilla double-slit experiment when speaking about topics of decoherence, entanglement, and how they relate to information -- making me think I must be misconstruing some basic QM principles.

[@brunomartinho7971]

I’ve been wondering about this for years as well. For all of the potentially meaningful results that the quantum eraser experiment delivers, it’s really odd that in the 20 years that it has been around, it hasn’t received almost any high profile coverage, which also makes me think that either my assumptions about it are wrong, or it’s another skeleton in the closet. Needless to say, I too would love Sean to cover this in the future.

[@eliasE989]

Very interesting, thanks.

[@ingenuity168]

Sean speaks so well.

[@anthonynewton7435]

Amazing talk. If Sean would try DMT,I think he could master the universe and conciousness. Great to hear this explained in 3dimensional logic. Still working hard to grasp the reality logic lol

[@ReddooryogaSH]

I still don't understand the probability issue. You observe an electron that is 10% up and 90% down. The universe splits in 2 and now one version of you sees it up and another version of you sees it as down. So as Sean points out, both results occur with 100% probability. If we want some frequentist approach to probability, in 50% of worlds it was up and in 50% it was down, so that doesn't give us the 10/90 split either. Where does that come from? Sean talks about the "thickness" of the slice, but what is that thickness meant to represent? It seems to be something added to the model: the physics of QM includes the amplitude for the electron to be spin up or spin down, so that number must represent something. So we just put that in. But it doesn't seem to be following from this many worlds picture. Had it been that case that there were 9 worlds in which it is up and 1 in which it's down, that would be a beautiful mechanism for giving us the probabilities, but that doesn't seem to be the case. Instead we're left with the fact that the probabilities work out in a certain way, but without any clear mechanism (at least as explained by Sean here, I have seen some more in depth explanations by him elsewhere, but they didn't make that mechanism clear to me either). He gives the analogy of a loaf of bread. You cut it into two unequal slices, so of course the probability that any atom will end up in one slice or the other can be unequal. But why? Because there are more atoms in one slice than the other! But there aren't more worlds in which the electron is spin down than spin up. So, again, _how_ does the "thickness" of the slice lead to us measuring the probability differently? It's certainly true that we _do_ measure the probabilities as given by the born rule. But many worlds doesn't seem to make any sense of that rule.

[@camspiers]

There have been many derivations of the born rule by Everretian proponents, e.g. Deutsch, Vaidman, Zurek, Wallace, and Carroll and Sebens, these derivations make more sense of the Born rule than what most interpretations often bring to the table, i.e. an axiom. Think of the amplitude as a new kind of physical magnitude, like density, only its a magnitude that for good epistemic reasons our credence's ought reflect. Carroll & Sebens' way of thinking about in particular begins with the observation that in the context of a measurement of a state where a superposition has unequal branch weights, in this case |O> |↑> |ω1> + √2 |O> |↓> |ω2> (O = observer, ↑↓ = spin, ω = environment), one can perform a unitary transformation on the environment (ω) in a manner that transforms the state in such a way that it must be represented by a superposition of three terms with equal amplitudes, |O> |↑> |ω1> + |O> |↓> |ω2> + |O> |↓> |ω3> (this might help pump the physical intuition about thickness), this in combination with what Carroll and Sebens call the Epistemic Separability Principle (roughly that in this case, the probability assigned to observing |↑> or |↓> shouldn't be affected by the environment) means that we should hold each equal amplitude branch with equal probability, and from this follows the Born Rule credences. They capture by summary that: "This route to the Born Rule has a simple physical interpretation. Take the wave function and write it as a sum over orthonormal basis vectors with equal amplitudes for each term in the sum (so that many terms may contribute to a single branch). Then the Born Rule is simply a matter of counting - every term in that sum contributes an equal probability." see 'Many Worlds, the Born Rule,and Self-Locating Uncertainty', Carroll and Charles T. Sebens.

[@ReddooryogaSH]

@@camspiers Thanks Cam, I'll check out that paper and see if it starts to make more sense to me. :)

[@chrisrecord5625]

Now for something completely different. Rob has a new, last thirty days, Ted Talk on Synthetic Biology and its risks. Worthwhile.

[@KILLERK260464]

Thanks!

[@Dillinger86]

Starting at around 36:28 is the money shot in Quantum Mechanics for me, it's like when I read Brian Greene's book The Elegant Universe, there was a money shot of a clear understanding of space-time in that book, and in this podcast there is a clear understanding of superposition and the many worlds interpretation.

[@PavlosPapageorgiou]

I'm confused by this: How do we know practically, not philosophically, what counts as measurement? In the double slit experiment I get it that the Schrodinger equation makes the photon interfere with itself. What equation says that when I put a film grain or a CMOS pixel somewhere in the wave function the photon will interact with it in a discrete way rather than put the detector in superposition? What if I want superpositions? I've seen many lectures that say "if you do a measurement you get a probability that's the square of the wave function blah blah". Does the cookbook or Copenhagen approach to quantum mechanics actually tell you a priori when you'll get superpositions and when probabilities? Or is there an empirical body of knowledge that says things like chemistry or microelectronics or neurons count as measurements, free-flying particles are superpositions, and if you want a bunch of atoms in superposition you have to do weird supercooled stuff? Even in practical terms that expectation seems ill defined.

[@lain11644]

Lol I love the coffee only exists in one cup analogy

[@acetate909]

Rob wrote an interesting novel called _Year One_ . I read it about 8 years ago when it came out. He is an interesting person and a talented writer.

[@welldun2]

Thank you, Sean! Question for you... given the fact that the last time I had a physics class was in high school back in 1991, if I wanted to pick up a book or two or perhap even a take course (today) to better understand the many points made in this podcast, what would you recommend?

[@deeliciousplum]

If you love manga and images as learning tools and if do not mind learning via a playful methodology, I highly recommend these two: 🍃 for quantum physics: www.amazon.com/Introducing-Quantum-Theory-Sciences-Discovery/dp/1840468505 🍃 a manga art-themed review of physics which includes quantum dynamics: www.amazon.ca/Manga-Guide-Physics-Hideo-Nitta/dp/1593271964 🍃 a manga art-themed review of relativity: www.amazon.ca/Manga-Guide-Relativity-Hideo-Nitta/dp/1593272723

[@adamschrepfer1086]

get Max Tegmark's book "Our Mathematical Universe" !!!

[@jjjccc728]

Excellent conversation. I do wonder about the conflation of the wave function with the underlining physical reality. The wave function of an electron is not an electron. It is a description of the probabilities that an electron is in one state or another. That is not the same as being an electron. It's like the difference between epistemology and ontology. Sean kept talking about there's only the wave function that's like saying there's only a map of Paris.

[@schmetterling4477]

The wave function is the description of the unmeasured quantum mechanical ensemble. Nowhere does the theory claim that it's the description of a single electron. That's usually the kind of claim that you will hear from people who are not actual users of the theory, including some theoreticians. Sean Carrol is a very smart cookie, but what he says about quantum mechanics is usually false.

[@TheOriginalRaster]

Good one... I'm not a physicist but I loved physics in high school and college and with my background I'm not a professional like Sean, but I'm also not uneducated (I've read numerous books on Quantum physics and 'Quantum Reality'): I'd like to add to what Sean says, but as he indicates if I felt I wanted to comment on the subject matter I can always create my own Podcast. Sean is not interested in my opinion, he gives us his professional opinion, but commentators here have to do their own work to pitch their ideas. With that in mind I would like to pitch my further ideas on the subject to the folks who read these comments: In the book titled "Quantum Reality" 11 different explanations for the reality of quantum physics are presented. I like two of those presented alternatives, and I think these are ones that Sean could also mention: Theory 8: We don't know enough yet and when further things are discovered an explanation of Quantum Reality that people find acceptable may be formed. Theory 11: There is no deep reality. Theory 11 is my favorite. Theory 8 is satisfying because we all can just relax, not worry about the implications of Quantum Theory, and we can hope that at some time in the future, with more information, things will be understood, and hopefully something will make sense. Or alternatively we at least will have proof about the nature of reality. When you accept Theory 11, that there is no deep reality... you do not 'split' the Universe trillions of times a second everywhere... instead, give up. There is no reality. Stop trying to make sense of Quantum field theory. Why assume that things should make sense. We live in the macro world where Newtonian Physics seems to apply and our brains have a 'common sense' component evolved only to deal with this world of our experiences. -------------------------- Summary: I use Theory 11, there is no deep reality. There's no realness of anything at the quantum level other than the equations. Whenever Sean yet again splits the Universe I just think to myself, nope, none of that is necessary. You can just stop trying to make sense of it. Just use the math and say there is no way to interpret the math that is real to us. Cheers!

[@b1zzler]

I think I might be a QBist after hearing Sean's cliffnotes on it. Not sure about all the "agent" stuff, but the general idea of the wave function being a way to characterize our ignorance seems pretty reasonable, almost like a rephrased version of the hidden variables interpretation.

[@BladeRunner-td8be]

Brian Greene and Sean Carroll are my two favorite physicists to listen to and learn from.

[@ReddooryogaSH]

Okay, another issue is bothering me: Sean mentions that every second 5000 atoms on your body undergo radioactive decay. This represents a quantum event that could have gone one of two ways (either decay or not decay), and given that there were 5000 of them, each with 2 possibilities, that's 2^5000 different worlds. But why are we only treating the 5000 that decayed in our world as having had the possibility to decay? Every particle in your body has a very small but non-zero chance of decay every second. This is obvious from the fact that someone in one of those 2^5000 other worlds might find that 4999 particles in his body decayed (which is what differentiates his world from ours), but he shouldn't conclude that there are only 2^4999 possible worlds, a tally which would not include the existence of our world. In fact, by the logic that says there are 2^5000 worlds, every version of me in every one of those worlds would ignore the existence of me (the particle that decayed in my world _didn't_ decay in his, thus he's not treating it as one of the particles that might have decayed). So, instead, there are not 2^5000 new worlds created every second, but instead something like 2^(10^27) worlds every second, because the probability that exists for _every_ atom in my body to undergo radioactive decay represents two worlds, one in which it did and one in which it didn't, and every possible combination decaying or not decaying for every particle in my body is thus included in the total tally of universes. Of course, the second is an arbitrary unit of time. We could also say that there is some non-zero chance of decay every millisecond, for instance. But I'm not really sure how to analyse this issue, so I'm going to leave it alone. I don't see any particular problem with this vast number of universes. I just don't think that 2^5000 makes any sense in this context.

[@seancarroll]

This is correct! The 2^5000 worlds is just a lower limit, I should have been more clear about that. In ordinary quantum field theory, the number of worlds in literally infinite. Quantum gravity suggests that the number might be finite, but that's quite uncertain right now.

[@ReddooryogaSH]

@@seancarroll Thanks so much for the reply Sean! And for the podcast too. :)

[@tc6961]

If each of us in essence "splits" roughly 5000 times per second based upon radioactive decay in our bodies and there were roughly 5178 seconds in this podcast (3600 + 1560 + 18) then if I did the math right (and someone please double check me as I could have screwed up) there should be 5000 to the power of 5178 more Sean's at the end of the podcast then at the beginning, which is a number that is over 19000 digits long! That my friend is a BIG number. This whole multi-world thing kind of reminds me of "snapshots" that some journaling filesystems make. Appreciate the mind expanding conversations!

[@schmetterling4477]

In reality MWI requires exponential splitting on the order of Aleph 1, which, I believe, is at least Aleph 2. A mathematical implementation of Aleph 2 is something like the space of all possible mappings of functions onto other functions. It's insanely large and I doubt that one can easily build convergent functions over that space. ;-)

[@vlex756]

The trouble with announcing at the beginning of an interview that you've prepped prior to the interview with the person interviewing you is that it casts doubt on the idea that the interviewer "stumbled upon" an extremely relevant point.

[@eenkjet]

Oddly MWI is the most metaphysically theistic. This is because Carroll's "Machine" (referring to the Universal Wave Function), contained within mathematical realism, is a Gödel machine in order to account for its ability to SFHD (solve for Heat Death) timelessly. The wave function's output requires +t and -t to possess all the necessary talent to accomplish step-by-steps through the algorithm handling BOTH self-organization AND entropy, AND agenty systems (teleonomic) in its branching block universes. Carroll's teleological UWF is God.

[@davidmcsween]

Hahaha

[@letsgobrandon329]

i have been listening since you was last on joe rogan, thank you sean

[@Dead_Twitch]

Is quantum many worlds interpretation useful in measuring the thickness of Big Bang probabilities? Could the collapse of the wave function be the precursor to the event that started the Big Bang? Also your example of the coffee going through the table wasn’t to off the wall to be considered weird if that probability was the example of the coffee becoming a superfluid, albeit it is strange if that were to occur without an external input.

[@The_Tauri]

You should add links to the guest's own website etc.?

[@ajosin]

Great talk 🙂. My question: Does many world's indicate we don't need to worry about the Higgs vacuum collapse? Following the quantum suicide logic: since there is always a universe where the vacuum doesn't collapse we will always have a conscious experience of the metastable vacuum. Also, does the vacuum collapse give the universal wave function a way to recycle/erase universes and free up Minkowsky space.

[@andrewpotapenkoff7723]

I definetly felt myself in superposition few times in my life when i was younger and loved experimenting

[@keybutnolock]

Now I need to go rest in a darkened room !

[@DaydreamNative]

OH MU MAMA! Excellent.

[@dizy3513]

I still cant get around what I hear... could you discuss how the "language" of mathematics describes the quantum world? Low brow science ex. I have "one" rock I throw it over my shoulder I have "zero" rocks... it seems all of our observations come in mathematical descriptions and try to put them into everyday language... is there a disconnect from ones and zeros and decimals to "hey there that's the electron" I mean it's a wave function yet a cloud chamber you see "one" trail made by "one" electron? I have no idea what I'm talking about now so someone pls elaborate lol

[@tmstani23]

+Sean Carroll Is it possible that the efficiency argument against reality being a simulation is solved by the observation phenomenon (observing a particle causes it's position to be actualized) in quantum physics? The efficiency argument is that a true simulation would only simulate parts of reality at a time when it was within a player character's visual reference frame. Many computer game simulations use this tactic to allow for creating massive game worlds without running out of pc resources. Could this observation effect be a way of creating efficiency in the system and thus lend more credence to the simulation argument?

[@welldun2]

In the many worlds concept, who and what action is required to create another version of the observer and thereby another world (let's call this cloning)? In other words, is it only the observer of an electron who gets cloned, or does that individual's observation of said electron also trigger a cloning of everyone else in the world? Does the cloning only happen when an electron is observed at the quantum level, or does it happen the minute we observe anything that is comprised of electrons even at the non-quantum scale (like a traffic light changing)?

[@larsalfredhenrikstahlin8012]

every interaction of every single particle where there is a probability involved splits off to different timelines.

[@brian-kt1rc]

If spacetime can bend, could it also spin. Could a blackhole cause space time around it to spin and in doing so have the appearance from observers in a seperate galaxy that matter orbiting the blackhole such as a galaxy, is orbiting the blackhole too fast compare to the gravity holding the rotation together.. Another question is how does the gravity gradient as you move further away from the event horizon affect the flow of time in that space. Does time speed up in regions further out compare to regions closer to the event horizon? And how does that affect the observations made by us observing from our galaxy, or is it negligible?

[@Dillinger86]

I love Quantum Mechanics

[@OOoO-kw1sf]

It is breaking my heart to know that future history will show that in this place and time, there were fewer then 100 people taking quantum physics seriously. And that they kept it secret from one another for fear of prosecution in the year 2020.

[@pettiprue]

.."if you have two electrons, you don't have two clouds". What if you have two observers? If you and Rob both look at the moon are you seeing two moons? Are you creating two distinct collapses of the same field? We can only ever experience our own collapsing wave, and yet it appears we are seeing the same seperate object?

[@mokopa]

On the subject of the Double-Slit Experiment...I am yet to learn of a mechanism of "detecting" which slit a photon passes through without destroying the "original" photon; or, in the case of an electron, without interacting with it (and therefor fundamentally changing its future). I'm not disputing the evidence, I'm uncertain about the interpretation

[@bluesteel7874]

I have questions : Which particles or waves have been observed capable of entanglement? What is the present practical means of establishing entanglement? In many worlds, aren't all other worlds except this one that I am aware of irrelevant and infinitely unobservable therefore their existence can only be relegated to faith, and what occurs in this world is completely random because I can never be aware of its consequence?

[@Wavesonics]

Anyone have a link to the other guy's podcast?

[@ReddooryogaSH]

check out his website: after-on dot com. Alternatively, I don't think he posts his podcasts on youtube, but if you search for after on or Rob Reid on your podcast app you should find it. Very good stuff. My favourite so far is his interview with George Church.

[@Wavesonics]

@@ReddooryogaSH Thanks!

[@leftblank6036]

At what point does matter have a wave function ? I’ve heard of scientists using macro sized molecules to perform the double slit experiment , why does it become harder to perform the experiment with larger objects? and if it was possible to propel large object like a tennis ball and it had a superposition would this make it possible to teleport it through space ?

[@qingyangzhang887]

Can you entangle two particles and measure the position of particle A, and measure the velocity of particle B and have perfect knowledge about both of them?

[@mortenolsen838]

No. Sorry you can't. The moment you measure one particle the wavefunction of the other collapses. It's one of the fundamental principles of entanglement.

[@cmdr.shepard]

Why don't the virtual particles which carry forces and constantly interact with particles (including electrons) cause "collapse"?

[@madderhat5852]

After listening to this I was wondering how you prove it? Sorry but I'm a kind of observation/experimental person.

[@MrBigcalm]

Thank you for this fascinating talk. I have a naive question for you. My brain, as yours and any, is made from particules and essentially works by sending an electric signal from one neuron to another through synapses (which you can show on a EEG for instance). That's roughly the way thoughts and ideas are generated. I guess we can thus assume a brain constantly collapses wave functions by locating an electron in a certain region and in some sense an idea would be the result of a measurement. Now imagine I consciously order my brain to generate a number between 0 and the infinite, so that I have an infinite liberty to choose this number. According to the many worlds theory, at the moment I'll write this number, I should create a branch, is that true ? If so, what would be the probability, or thickness, of a branch in this case ? One over an infinity, meaning 0, so none of these branches should exist. Isn't that paradoxical ?

[@johnphil2006]

A complete guide of quantum mechanics

[@rollingrock3480]

This podcast is a real sleeper. I suspect it will be huge one day. As of now it's 18 July 2019 he's at 38k subs. Let's see where he's at in 2 years.

[@toohardfortheradiopodcast]

This episode in particular!

[@BenJamin-rt7ui]

So can I use a quantum random number generator to play the lottery, thus knowing I will live in a world where I am guaranteed to win?

[@eboomer]

In one of the many worlds, yes. As for which one "you" will become, well - who knows? But it probably won't be the one where you won. So most of your "selves" would have wasted their money, and the average wealth across all of your "selves" will be less for having played the lottery.

[@BenJamin-rt7ui]

@@eboomer Thanks for stating the bleeding obvious.

[@reculture]

Welcome to the Everettian Lottery where everyone wins jackpot at least once! ...would be pretty catchy slogan tho

[@SG-ig2eu]

@@eboomer I enjoyed reading this

[@cmdr.shepard]

You should also do a podcast with John Michael Godier of Event Horizon channel.

[@brian-kt1rc]

About quantum mechanics, looking at normal mechanics, for events to happen they need time and space. Within time and space then, matter follows the laws of physics, as far as i know all of which are variations of the principle of the action of least energy. In any case, the question arises still, what executes or implements or enforces or gives rise to the laws that events must follow? Or like in a computer it would be a cpu executing instructions. What is this 'processor' and can we ever discover it? Quantum mechanics follows some laws of probability, but what mechanism gives rise to that probability is obviously the question. I am just adding further as above, the question of what would be the thing that then causes that mechanism, if any, to have authority? Or in short, what about the universe decides the outcomes of events or calculates the outcomes of the laws of physics?

[@GnomiMoody]

So when Sean said "it's l ike you're taking the universe and slicing it in half." I wonder if this has anything to do with Dark Energy and why the universe is expanding and it's expanding faster and faster. Because we're branching the wave function and we're branching it faster and faster as we do more science.

[@MagruderSpoots]

"How many of you are there?" Depends on how many times the multiverse has branched.

[@guiltylover]

I like your lectures and I like the fact you have the power to tell the world that are Top people Are told not to pursue quantum reality which clearly holds the key to life. We seem to push a lot of money into Cern which has produced and sloved a few issues , but now seems underpowered to move forward now. I dont profess to understanding all I have read on quantum messurement as I understand the differance views but its impact on everyday life is the hard part.

[@Kelthan54]

I'll listen to the podcast Sean, but I still don't understand the principle of Everett's interpretation, as I'm sure you'll talk about it in that podcast For me, parallel universe is indeed parallel, and if you take a choice or action, in the several other worls where you exist at the same point of space and time you'd take the same action, as for a quantum effect which would in theory take the same action in all worlds. I'm not sure I'm being very clear, but I think parallel means parallel

[@GnomiMoody]

You know how an electron has a probability of being in a certain place? When you measure it, you will get a result, but each one of those probabilities represents another universe.

[@Beradikals]

Calvin Blanchard ... you accuse people of being “inhumanist” and you trolled every comment on this comment thread with negative “inhumanist” comments. You must of just read some idea from someone else to use that term... In regards to “this is more dangerous than religion and politics,” you don’t see individuals blowing themselves up or going on mass shooting sprees in the name of Sean Carroll, or creating state nations under Mindscape flags, or limiting immigrants because they’re not pale skin Carroll’s. This is a conversation of intellectuals. This is one way of how things move forward. You’re not shining a light onto anything other than your desire to be a troll attempting to gain attention. Add real content to the convo. Not noise.

[@Kelthan54]

Oh i understand, I just don't agree because of stuff i lived. I think parallel means paralell in the following way : A quantum event is an event and would take the same choice in any different number of parallel world, which would had only some sligth changes in dimensions for example As thus, no need for embranchement of reality For me the fact that a quantum experience isn't reproductible, in one and same world, doesn't mean it's splits the world in other worlds, but who could tell ?

[@websurfer352]

Let’s say you have two possible locations for an electron, one more probable than the other?? My question is what makes for the difference in probability?? There must be some underlying principle determining the difference in probability?? If the electron is potentially everywhere, but is constrained by probability to a range of locales, then what causes such a range of probability values?? I suppose the real question is what makes for the difference between consistent and decoherent histories??? The macroscopic world obeys certain laws and principles, if such a macro world is emergent from a more fundamental quantum reality, then by extrapolation downward in scale, could the rules of the quantum world also be emergent from a still more fundamental underlying reality?? If so, what would that reality be??

[@simrankour1239]

Nice👍🏻👍🏻👍🏻👍🏻👍🏻👍🏻

[@Ken-yp1dg]

Would entropy exist in the quantum level?

[@eenkjet]

With MWI it exists but it's trapped in the theories branching block universes. Accordingly, Carroll describes our experiencing entropy as "psychological time". This psychological time is our brain "surfing" entropy along its frozen worldline. Seems this would qualify as substance dualist.

[@robertw1871]

I agree with Sean’s interpretation, but not exactly in the way explained. ‘Splitting’ is a way of thinking of it, but that assumes time is something real. I’m thinking the universe somehow exists without time, in a way that all possible results are occurring without the concept of a clock ticking. What we experience as time is what I have no idea about. Is humanity’s inability of thinking without a concept of time making the question fundamentally impossible to understand. So I propose the seemingly simple question; What is Time? Everything will follow if this is answered; at least in my ignorant, fuzzy frustrated curiosity. Infinities, path integration, wave functions all go away or make sense when energy isn’t experiencing time, but is still somehow evolving. Sorry I can’t make the thought more clear, it’s because I don’t understand it.

[@chrisrecord5625]

I am pretty sure this question has been answered since the many worlds theory is of interest to the quantum information community but why doesn't the no-cloning theorem prevent exact duplicates (clones) of someone when branching occurs? More importantly (and I suspect Avi Loeb might have missed this in the podcast on Oumaumau) in 1962 papa Oommaumau (mow, at times)) was observed by many in the United States and elsewhere.

[@camspiers]

The no-cloning theorem tells us that an exact quantum state can't be cloned. This isn't what is happening in the case of measurement and what you call "cloning". In a measurement (or more precisely cases where superpositions decohere with the environment) there is a difference in the resulting duplicates, in particular the duplicates become entangled with the quantum state being measured, and each duplicate has interacted with a different "part" of the superposition, as such the quantum state of the human isn't being cloned as each differs exactly by which part of the superposition it has interacted with.

[@chrisrecord5625]

@@camspiers Thanks so much, Cam. My use of the "cloning" term came about, as follows: 1:03:34 (Rob-transcript) "The most intriguing thing that pops out (re MWI) is the notion that there are octillions of me, quote-unquote, out there." 1:03:47 (Sean) "There are two versions of your future self, but they're separate people." (Amoeba comparison follows) They continue on... Frankly, I didn't really buy-in here. There could be two exact clones created and branched to separate worlds but even if their experiences diverged from that point forward, in such worlds, they were exact clones prior to a new experience. Here is where I insert the disclaimer that I have no science, much less, physics training, hence I defer to those who do and promise to keep being autodidactic! 😆

[@camspiers]

@@chrisrecord5625 You are right to be confused, the usage of "exact clone" here is unfortunate, as Sean well knows the quantum state of the two observers differ by the effects of what part of the superposition was observed. The crucial point is that the no-cloning theorem tells us that a quantum state can not be duplicated, and that is precisely right, in Everretian QM quantum states aren't cloned, the result states in the different branches are not identical, they differ in virtue of having interacted with different parts of the measured superposition.

[@chrisrecord5625]

@@camspiers Thanks again. I was going to comment that my issue may have a semantic foundation but hesitated.

[@KITCHENCOOKIEJARTHIEF]

Interesting

[@davidbrown9414]

I think this is a mistake of assuming a good model must tells us something fundamental about reality in addition to being predictive.

[@deborahansari2760]

So do the lives of animals also branch off into many worlds?

[@kadourimdou43]

Apart from the circular answer that QM says you can't know position and momentum. Why can't you or why is QM the way it is. Is there a deeper answer or is this the bottom of reality.

[@schmetterling4477]

Yes, the ensemble description is a wave theory. Waves don't work any other way. They have uncertainty relations in the classical case (water, acoustic, Maxwell etc.) just as well. Your Wifi router has an algorithm that uses the time-energy uncertainty to shape the spectrum of the RF signal in a certain way the suppresses interference from reflections on walls.

[@Kalumbatsch]

To completely flip this Rob should have done the introduction.

[@IbnFarteen]

Many Worlds still doesn't help us understand anything about where the randomness of events comes from?

[@EannaButler]

Neither speaker goes 'aah' or 'umm'. That's really hard!

[@chrisrecord5625]

This podcast seemed geared for much of Rob's audience and less so for Sean's community. To me, it covered too much prior Mindscape ground. The Sean-David Alpert discussion was more stimulating, at least, again for me, but that overlap was mentioned at the get-go. However, pilot wave thinking is for me.

[@GnomiMoody]

Hidden variables have been pretty much dunked on by Bell’s Theorem.

[@chrisrecord5625]

@@GnomiMoody Thanks, first I am equating PWT with de Broglie-Bohm theory which Bell had some respect for only saying it did not account for locality, Cambridge University Press, 1987. Second, I am way over my head in nearly all of these discussions!

[@grayaj23]

@Calvin Blanchard And yet here YOU are gatekeeping the shit out of everyone who comments. I guess what you're doing is somehow "worthwhile" and not a wast (if only in your own mind).

[@EannaButler]

"And when they were only half way up, there were.. " 37:31

[@dk6024]

That grand old Duke of York.

[@justinpaul3458]

It is sad to think about all the different branches where I don't/didn't listen to this episode.

[@RetroPhaeax]

Imagine those universes where non tunneling, with all objects, appears as improbable as tunneling in this one.

[@FAAMS1]

My latest scary conspiracy theory is that Dark Matter could be an advanced form of an AGI spread over the observable Universe that evolved itself to not being easily interacted with even if detectable by gravity discrepancies...we are being watched...xD

[@jugika]

Ptriests!

[@szkoclaw]

I have no idea why are people confused with Heisenberg's principle and position/velocity debacle. Take a 1/1000000th second exposure photo of a car. You know perfectly where it is, but you have no idea how it's moving. Now take a 1s exposure photo of a car. You know the speed, but you can't tell where exactly it was during that second, because it wasn't in one spot at the same time. And it isn't just measurement. Without time, velocity simply doesn't make sense. And with time, a position of a moving object doesn't make sense. That's why velocity and position can't really "exist" together.

[@markr1461]

A ceiling fan under an oscillating strobe light is also a good metaphor.

[@rodrigosilvanader]

If some binary event has a 99% (A outcome) vs 1% (B outcome) probability, why isn't it proposed that the universe splits N times, where 99% of N has A outcome?

[@schmetterling4477]

Because then everybody could immediately see just how nonsensical this is... imagine if the outcome probabilities are 1/pi and 1-1/pi...

[@websurfer352]

Let’s say you’re in a home in Los Angeles, but there is a world where you are in a home in New York?? Now, what makes being in a home in New York more decoherent than being a step away to the right from where you are?? Is it because you are entangled with your environment in your home in Los Angeles?? If so, then the pivotal factor in determining decoherence and consistency is you?? Your awareness?? Your entangled state??

[@panlan1]

what i learned thus far: unlike socrates, einstein was no gadfly....;

[@wootcrisp]

I am always impressed with your clarity of thought Sean. This was a very fresh way to frame the curiousities of QM. For anyone interested in a random recommendation, there is a somewhat related Google Tech talk about the quantum "conspiracy" that is quite good: kzbin.info/www/bejne/mnbElpaLqqqknMU

[@gellis7975]

William of Ockham disliked this video.

[@erictko85]

Al Fresco lol

[@mokopa]

Starting this podcast at any random time, a wavefunction collapses and with a certain probability you will find the interviewer being interviewed by the interviewee, or vice versa.

[@vlex756]

The "missing mass" of our Universe is just the infinitesimal weight of all those bad life decisions adding up across gazillions of split other universes.

[@chrisstewart4288]

This video sounds heavily edited, especially from 29:00 - 31:25. Was it edited? If so, I prefer the free form format better. Still, was a great podcast.

[@ReddooryogaSH]

This was also an episode of Rob Reid's podcast, After On. He generally puts out an edited version for free and a longer unedited version on his patreon page. I think that's true of this one as well.

[@SG-ig2eu]

They finish each others sentences.

[@mcdenyer]

we need video or this podcast didn't happen.

[@Jason-gt2kx]

I bet the branched off version of Sean that got all zeros TWICE is really confident in Many Worlds right now...

[@Well_Earned_Siesta]

Does this make quantum mechanics the world's most advanced "cargo cult" ?