The Multiverse just Got Bigger: An Upgrade for the Many Worlds Interpretation

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  • Опубліковано 1 тра 2024
  • Check out my course on quantum mechanics on Brilliant! First 30 days are free and 20% off the annual premium subscription when you use our link ➜ brilliant.org/sabine.
    The idea of parallel universes is both crazy and not. In physics, it's prominently represented by the “Many Worlds” interpretation of quantum mechanics. A group of physicists now says that the many worlds interpretation contains many more worlds than we thought so far, meaning the infinite number of multiverses could be infinitely larger. Let’s have a look.
    Paper: arxiv.org/abs/2403.10895
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    #science #sciencenews #physics #multiverse
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КОМЕНТАРІ • 1,4 тис.

  • @NDFlyFisher
    @NDFlyFisher 26 днів тому +554

    I had a statistics professor in grad school who was fond of saying, “If you torture numbers long enough you can get them to admit to anything.”

    • @brothermine2292
      @brothermine2292 26 днів тому +31

      Another adage is "lies, damn lies, and statistics."

    • @scotttovey
      @scotttovey 26 днів тому +25

      Technically, it's not the numbers that are admitting to anything, the person manipulating the numbers, is simply lying.
      Anyone can come up with a theory of this or that, this is not a problem. I read an individuals interpretation of a Bible passage and then decided to read the Bible passage. The only way to get his interpretation to work, is to completely rewrite the passage. He however, was quite confident that his interpretation of the passage was valid.
      Problems do not come with the abundance of theories and ideas.
      Problems come with the abundance of pride and egotism that cannot handle when the fact of reality hits the theorist in the head.
      If one is so stuck on the brilliance of one's theory that one cannot be wrong, odds are greater that the theory is wrong and one is simply too busy being right to prove oneself wrong.

    • @MagMar-kv9ne
      @MagMar-kv9ne 26 днів тому +3

      @@scotttovey Yup. A brilliant analysis. Thank you. Btw, it is EXTREMELY hard to overcome this problem. I had worked very shortly at college with reseachers - NOT physics, lol - and it is extremely widespread, this attempt at lying to yourself. I also caught myself doing it ;)

    • @user-ek8gs4ij4r
      @user-ek8gs4ij4r 26 днів тому +1

      Brilliant.

    • @serioustoday
      @serioustoday 26 днів тому

      @@brothermine2292 Benjamin Disraeli?

  • @People.United
    @People.United 26 днів тому +117

    " ... at least I do in this universe."
    Best line ever.

    • @martifingers
      @martifingers 26 днів тому +11

      Sabine's humour has one of the qualities of good comedy - the jokes arise entirely from the context.

  • @prototy
    @prototy 26 днів тому +51

    I propose that we officially name a collection of particles a “party” of particles.

    • @altrag
      @altrag 25 днів тому +1

      Far too late. It was already named a "zoo" decades ago.

    • @prototy
      @prototy 25 днів тому +4

      @@altrag that’s just the name of the types of particles.
      “In particle physics, the term particle zoo is used colloquially to describe the relatively extensive list of known subatomic particles by comparison to the variety of species in a zoo.”
      There’s still room for a collection of particles to be called a “party” ❤️

    • @phoenix007ism
      @phoenix007ism 22 дні тому

      A partycle?

  • @wetwingnut
    @wetwingnut 26 днів тому +245

    I'm beginning to think that the problem with physics lies in physicists believing that the Mathematics and the Physics ARE THE SAME THING, rather than that mathematics is a (very powerful) framework for humans to conceptualize physical phenomena.

    • @jjptech
      @jjptech 26 днів тому +20

      So, basically the problem with physics are physicists 😅

    • @Olack87
      @Olack87 26 днів тому +48

      You are right of course to an extent. The problem is that often extremely abstract math have predicted real physical phenomena that no one would have guessed existed. A singularity in the equations of relativity predicted black holes before we had a chance to realize their true physical existence. So it's tough to tell when some mathematical crazy quantity indeed corresponds to real physics or is just evidence towards having a wrong theory.

    • @TheGuyCalledX
      @TheGuyCalledX 26 днів тому +6

      Exactly. Going deep into pure math, you'll find many things that have almost no real world applications, because they often don't have analogs to the physical world.

    • @iyziejane
      @iyziejane 26 днів тому +12

      You think a person who spends 10, 20, 30 years on theoretical physics does not have that thought? :P

    • @HatsuneSquidward
      @HatsuneSquidward 26 днів тому +18

      But the fact that it happens/ has happened ever, and surprisingly frequently at that, begs the question of if the universe is fundamentally mathematialcal in nature. If so this approach becomes more justified.@@TheGuyCalledX

  • @danielcook1271
    @danielcook1271 26 днів тому +87

    Sabine, long term fan here. Have watched your channel evolve and you’re the best at what you do. I only wish this channel (and UA-cam) existed when I was a teenager deciding on whether to pursue chemistry or physics at university. Your daily updates and explanations on quantum physics and general relativity give me precisely what this Einstein/Dirac/Feynman/Hossenfelder fan boy needs.

    • @SabineHossenfelder
      @SabineHossenfelder  26 днів тому +25

      Thanks for the kind words 😊

    • @TheDdm1234
      @TheDdm1234 26 днів тому

      ​@@SabineHossenfelderdo you exist in the universe, or the multiverse, or both?

    • @PPP-on3vl
      @PPP-on3vl 24 дні тому

      ​@@SabineHossenfelder u are getting old

  • @eljcd
    @eljcd 26 днів тому +103

    I love that with Sabine you always learn something new, but
    "the quanten" IS another level of knowledge...

    • @hydewhyte4364
      @hydewhyte4364 26 днів тому +3

      She does make education entertaining ...

    • @chris.hinsley
      @chris.hinsley 26 днів тому +6

      It’s another level of socks !

    • @matthiaseberlein3451
      @matthiaseberlein3451 25 днів тому

      @@8gjames Correct. It's "Die Quante" in German.

    • @thesiegfried
      @thesiegfried 25 днів тому

      @@matthiaseberlein3451 Weirdly, I am a German and have never heard the word "Quante" with regard to feet before watching this video.

    • @SomeoneExchangeable
      @SomeoneExchangeable 25 днів тому +1

      @@thesiegfried It is, as far as I know, Berlinerisch

  • @musesesesese
    @musesesesese 26 днів тому +20

    Maybe the reason we can measure large objects and not quantum ones precisely is due to the fact that large objects are made of constantly interacting small objects that effectively just measure each other via interaction, we know once something interacts with it that it is determined, but im probably missing something
    edit: probably clearer to think of it as interaction with an object is necessary for measurement and quantum objects are not necessarily being interacted with prior to being measured, but macroscopic objects and their individual quantum parts are always interacting with each other. This doesnt mean that things are undetermined before being interacted with either, just that we wont be able to know the outcomes without some kind of data which we get from some interaction, making the interaction itself look like the cause, when it really could be that we are just missing something

    • @altrag
      @altrag 25 днів тому +3

      > but im probably missing something
      You are. You're missing the uncertainty principle. Even if we didn't have any "large objects" getting in the way, it would still be impossible to measure quantum objects precisely because they fundamentally aren't precise.
      To analogize (and please remember that all analogies are necessarily incorrect in some manner - if they were a perfect representation they wouldn't be analogies, they'd just be the thing!), think of plucking a guitar and then asking what point on the string is the "G". The question doesn't even really make sense - the "G" isn't a point on the string, it's the shape of the string's vibration - and if you want to dig deeper it's not even _just_ the string - it's the combination of the string you caused to vibrate, the air molecules the string caused to vibrate, the membrane in your ear (or on a microphone) that the air caused to vibrate, the neurons in your head (or the electronics picking up the microphone) doing... whatever they do... and so on.
      Of course that's just with our current understanding of quantum mechanics. It's anyone's guess what a deeper theory will reveal. There is reason to believe it won't go back to being a classical theory, but "reason to believe" is not proof. My personal guess is that whatever the next theory is will be as different from quantum mechanics as quantum is from classical mechanics - and be that much more difficult again for us mere mortals to understand with just our intuition.

    • @lubricustheslippery5028
      @lubricustheslippery5028 25 днів тому

      @@altrag It's hard to know if "quantum object fundamentally aren't precise" because you can't measure it without interacting with it. I tried to read up on bells inequality theorem and no hidden variable theories and it just got more complex and less convincing the further towards real experiment I got.
      Sabine is always at point so watch this ua-cam.com/video/XL9wWeEmQvo/v-deo.html
      And it's not that easy to explain why the shoe analogy is not working, especially if you go from real observations and experiments instead of other theories that could be false.

    • @camelCased
      @camelCased 25 днів тому +1

      Hm, I'm not sure about quantum objects not being interacted. They seem to be in constant interaction with other quantum objects, don't they? So, the question still remains - at what point and why does some kind of interaction cause them to suddenly behave differently than when they are interacting with each other on their own?

    • @altrag
      @altrag 24 дні тому +1

      @@camelCased > They seem to be in constant interaction with other quantum objects, don't they?
      If you're just talking about some arbitrary particle in some random place on Earth then sure. But we don't do quantum experiments in that context. We go to great lengths to eliminate those interactions specifically because it will "behave different" if you don't have full accounting of every single interaction the particle participates in.
      It's why pretty much all quantum experiments are done in a vibrationally-stabilized vacuum chamber at cryogenic temperatures, and often in a magnetic trap to boot. Anything we can do to prevent any stray particles or photons from interfering with the experiment.
      > at what point and why does some kind of interaction cause them to suddenly behave differently
      Yep, that is the question. One we don't have an answer to. We can measure it. We know it happens. But we have no idea _why_ it happens.
      Many worlds (whichever variety), Copenhagen's wave function collapse, pilot waves... these are all potential explanations, but they're all philosophy at this point. Mathematically they're all equivalent so there's no way to construct an experiment that would determine which one is "right" - if any of them. It's entirely possible (I'd even say likely) that the right answer is something we haven't even thought of yet.
      Until something new comes along to give us more insight, the "right" answer is simply the one that best helps you understand the problem you're working on - you can even use a different "right" answer for each problem you work on!

    • @lubricustheslippery5028
      @lubricustheslippery5028 24 дні тому

      @@camelCased How do you now they behave differently when you can't observe it. You observing/measuring it is interacting with something big and less quantum.
      I can't either understand how it could be that it's binary the wave function either collapsed or not. I can imagine it's something more like the law of big number where interacting with more particles reduces the uncertainty similar on the more you have thrown an dice the mean will get closer to 3.5.

  • @christiandior8726
    @christiandior8726 26 днів тому +18

    Thank you for calling BS on bad papers! We need more people like you!

    • @EinsteinsHair
      @EinsteinsHair 26 днів тому +1

      I just found a small channel called Sholto David. Some of his videos debunk things such as crystal healing. But other videos find published papers with manipulated data, or reused data. He has gotten a couple of papers retracted by journals.

  • @mrfriendly9956
    @mrfriendly9956 26 днів тому +30

    "I like this paper, in this universe", perfect start!

  • @sosomadman
    @sosomadman 26 днів тому +18

    The quantum world is like a pair of glasses with the wrong prescription, with things appearing in 2 place at the same time

  • @fabkury
    @fabkury 27 днів тому +54

    I secretly wish every major language of the world had its own Sabine-In-Chief. To communicate science and defend the people from myths.

    • @havenbastion
      @havenbastion 26 днів тому +4

      I believe she's carrying the Torch of Sagan.

    • @chris.hinsley
      @chris.hinsley 26 днів тому +3

      Your not listen clearly enough ! She is openly saying it’s all crap !!! :)

    • @fabkury
      @fabkury 26 днів тому +1

      @@havenbastion I like your analogy.

    • @ShonMardani
      @ShonMardani 26 днів тому +1

      @@chris.hinsley She is saying her audience is crap and germans figured it all out many years ago but it is too complicated for others to understand.

    • @chris.hinsley
      @chris.hinsley 26 днів тому

      @@ShonMardani well you are but what am I… to quote the Bart.

  • @Thomas-gk42
    @Thomas-gk42 27 днів тому +46

    Measuring a new SH video sometimes opens a portal to another world. These guys must be right.

  • @PatFarrellKTM
    @PatFarrellKTM 26 днів тому +8

    “When you can measure what you are speaking about, and express it in numbers, you know something about it, when you cannot express it in numbers, your knowledge is of a meager and unsatisfactory kind; it may be the beginning of knowledge, but you have scarely, in your thoughts advanced to the stage of science.”
    ― William Thomson aka Lord Kelvin

    • @BenjaminCronce
      @BenjaminCronce 24 дні тому

      I subscribe that the world is fundamentally abstract and attempting to force the world into an objective state is ultimately a false analogy. Heisenberg's uncertainty is but one of many forms of this. There are classes of problems that are fundamentally unsolvable if you attempt to objectify them and they only way to solve them is to treat them abstractly. There are cases of this that have happened in computer science. I remember reading a case where it was proven that a problem was unsolvable only to have it solved once someone created whole new axioms. This is the problem with reasoning. Godel's theorem says that there is no one complete system of logic. Sometimes the only way to solve a problem is to CHANGE LOGIC. This is an abstract problem.
      I actually recently watched a math video talking about a problem that was claimed to have been solved millennia ago, but when modern mathematicians attempted to investigate it, not only did they discover that the documented solution did not solve the problem, but that the problem was proven to be unsolvable. It took several centuries of modern math before someone realized that that mathematical system from back when was actually different and that if you changed the rules of math, the problem was solved, and was an actual solution. It wasn't just playing with math to make a useless solution, but an actual real solution. Our modern math was unable to solve the problem.
      Numbers themselves are but abstract concepts that do not actually exist and their value only exists within whichever mathematical system you choose to use.

  • @benlap1977
    @benlap1977 26 днів тому +30

    The world of physics is like Disney Studios in the 80s: trying to recreate the past glory, but running out of ideas.

    • @Mlab923
      @Mlab923 26 днів тому +4

      You should get patent for your words.

    • @audiodead7302
      @audiodead7302 26 днів тому +3

      I agree that the flailing around of the current physics community shows a lack of coherence direction. But maybe that is what is needed before a new direction emerges.

    • @MartianSolarbuddy
      @MartianSolarbuddy 26 днів тому +1

      Physics needs a “Michael Eisner” . . .

    • @benlap1977
      @benlap1977 26 днів тому +3

      @audiodead7302 I do agree. Evolution is never linear and always came in leaps. There are periods in the doldrums where not much seems to happen and there are periods of explosion. It certainly feels like quantum physics is in the doldrums. Astrophysics, on the other hand, is exploding.

    • @altrag
      @altrag 25 днів тому +2

      Just like it's always been. The real "problem" with physics is that the last great paradigm shift happened recently enough that it's still fresh in mind (culturally speaking) but at the same time long enough ago that we current generations feel like we "missed out". Prior to the late 1800s, nothing super exciting had really happened in physics for like 200 years. And prior to that period in the 1500-1600s (including Galileo, Kepler, Newton and that group - the people who defined the basis for what we now call classical physics), there wasn't any major leaps since the time of Euclid.
      Not to say _nothing_ happened during those periods of course. People were and still are making incremental improvements to the knowledge that existed at the time. But there's really only been 3-4 massive paradigm shifts throughout all of history - the Greeks introducing concepts like mathematical rigor and logic into the study of "natural philosophy" (possibly divided into a couple of separate movements if you want to split pre-Euclid focusing primarily on logic, and post-Euclid that demands the rigor aspect), classical mechanics (primarily initiated during the 1500s-1600s as noted) and quantum mechanics (initiated in the late 1800s up to the mid 1900s).
      That's really not a lot when you think about it in historical terms. We currently just happen to be in one of those "incremental improvement" periods and waiting on the next paradigm shift. Drawing a trend line across the previous 3-4 makes it feel like there's an exponentially decreasing amount of time between paradigm shifts, but 3 data points is not really a solid basis for making that kind of claim. We really shouldn't expect the next paradigm shift within our lifetimes - realistically that's _probably_ not going to happen. It might of course, but it's not something to place bets on.

  • @davidtatro7457
    @davidtatro7457 26 днів тому +13

    The best thing about this is contemplating the sheer magnitude of cheese and kitty cats that might exist in all these extra worlds.

  • @johnrowson2253
    @johnrowson2253 26 днів тому +12

    A historical perspective of mathematics helps explain interpretative problems. When algebra was being used during the ‘dark ages’, there were crazy ideas about ‘x’. Two authors I recommend are Mario Livio who has several titles about the history of stem, and Nick Lucid.

    • @G3Kappa
      @G3Kappa 26 днів тому +10

      It would be cool if you actually explained what those crazy ideas were lol

    • @brianhourigan
      @brianhourigan 11 днів тому

      ​@@G3Kappa x was y and z at the same time. Superentangelbra

  • @Sharon-hr2
    @Sharon-hr2 26 днів тому +104

    Out of all worlds, why did I get stuck in the one where people believe in many worlds?

    • @grahamritchie672
      @grahamritchie672 26 днів тому +3

      Better than being in the one where Elvis died.

    • @wb3904
      @wb3904 26 днів тому +2

      At least in this world your body can form, UA-cam exists and you can formulate this response 😊

    • @LuisSierra42
      @LuisSierra42 26 днів тому +1

      @@grahamritchie672 In my world Elvis is immortal

    • @mathiaslist6705
      @mathiaslist6705 26 днів тому +2

      What is wrong about it? Unless they interact with our one it doesn't matter or should it?

    • @not2busy
      @not2busy 26 днів тому +2

      ...because people are infinitely gullible.

  • @NeonVisual
    @NeonVisual 26 днів тому +62

    Dark energy is just a rounding error by the dev of universe.exe

    • @chris.hinsley
      @chris.hinsley 26 днів тому +9

      Floating point formats are crap aren’t they !!!

    • @SigEpBlue
      @SigEpBlue 26 днів тому +6

      Oh man, if this universe runs Windows....

    • @chris.hinsley
      @chris.hinsley 26 днів тому +3

      @@SigEpBlue blue screen of big bang….

    • @valrond
      @valrond 26 днів тому +1

      @@SigEpBlue More like Universes OS

    • @chris.hinsley
      @chris.hinsley 26 днів тому

      Sabine should cover p-adic number systems…. In her own sweet way.

  • @waltergith6535
    @waltergith6535 25 днів тому +2

    Wow, this is epic Sabine. The question what a measurement is and whether an observer exists or not is groundbreaking. Physicists are really onto something here. Could you please follow up with more videos on every aspect of those questions. Thank you.

  • @mskiptr
    @mskiptr 26 днів тому +17

    This all (both the paper and the video) sound like a severe misunderstanding of the MWI.
    It's only about "worlds" in sci-fi (and pop-sci, but that's often the same thing). From the mathematical perspective it's just about not having some special observers that cannot be in a superposition of two base states for whatever reason. Whenever you have an experiment where you measure something and "cause a collapse", MWI says that there wasn't any collapse and the measurement aparatus is just entangled with the experiment now. The aparatus behaves as if it had measured only one base state because you're only considering exactly one base state for the aparatus. That's it.

    • @MrSpikegee
      @MrSpikegee 26 днів тому +1

      Same here. Sabine hates the many world interpretation for some reason and will take any occasion to step on it, like this last paper which seems really d.

    • @mskiptr
      @mskiptr 26 днів тому +1

      @@MrSpikegee I guess she thinks it's about "parallel worlds" and that the entire reason for it is to "get rid of randomness by choosing every possible outcome". That would indeed be pretty pointless, but that's sadly how MWI is often presented.

    • @altrag
      @altrag 25 днів тому +1

      Funny thing is, it doesn't really matter. The math is the same either way, so until we can get a better understanding of what a "collapse" really is, the interpretations we use to describe it are mostly just personal preference.
      Relating this paper to your preferred interpretation (and mine if I'm being honest), it would imply that the state space getting entangled is larger than we thought rather than the multiplicity of universes being larger than we thought.

    • @toddturner6
      @toddturner6 24 дні тому

      And there you have it. This man is correct. Somebody give him an award or something for pointing it out. At least a cookie? 🍪😊

    • @sh4dow666
      @sh4dow666 24 дні тому +1

      @@altrag The math is *mostly* the same, except the MWI doesn't need an additional collapse postulate. You can cheat a bit by not including the collapse in your equations ((and applying it "off the books" afterwards)), but that doesn't change the fact that the Copenhagen interpretation requires an additional mechanism (ie. "spooky action at a distance").

  • @Nomaken2
    @Nomaken2 26 днів тому +16

    Basically i think the mistake is in assuming photons move because we lose energy in one place and gain it in another and the distance and time between them implies there was linear movement.

    • @EinsteinsHair
      @EinsteinsHair 26 днів тому

      You can have a tabletop experiment with a laser pointed at a target. Then you can blow smoke everywhere between the two, and the smoke will light up as if the photons were within a narrow path all the way between the laser and target. Lying photons!

  • @seanmostert4213
    @seanmostert4213 27 днів тому +8

    Thank you for sharing Sabine.
    I would like to propose an alternative hypothesis that might offer a fresh perspective on the nature of "what a measurement is" in the context of quantum mechanics.
    1.) Consider, for a moment, the analogy of the wave function of a particle in superposition akin to a Lagrange point in classical mechanics-a position of equilibrium between competing forces. In the quantum realm, these equilibrium points may manifest as multiple potential states within a superposition, each acting as a tipping point that could influence the path of state reduction upon measurement.
    2.) From a geometric standpoint, we define a "point" as an exact location in space and a "line" as a continuum of points. These concepts are integral to the process of measurement, which fundamentally involves distinguishing a specific state from the realm of possibilities. In essence, to measure is to define what something is by discerning it from what it is not, employing a comparative framework that leverages change between two diametrically opposed states.
    When an observation or measurement is made on a particle in a state of superposition, it necessarily influences the system. This influence can be conceptualized as imposing a 'change'-akin to introducing a fluctuation or disturbance-that tips the system over one of these quantum Lagrange points.
    Moreover, consider the broader concept of 'change' as analogous to vibration, which encompasses regular or periodic motions around a central position or fluctuations within a system. This metaphor extends aptly to quantum mechanics, where the wave function itself represents a form of vibration. Therefore, when we interact with a superposition by measuring it, we are essentially interacting with the vibrational state of the wave function, introducing new vibrations that affect that wave, that then results in a definitive state.
    I am eager to hear your thoughts on this hypothesis and whether such a conceptual framework might contribute to our understanding of quantum measurements.

    • @SabineHossenfelder
      @SabineHossenfelder  27 днів тому +6

      The problem is to do it locally.

    • @seanmostert4213
      @seanmostert4213 27 днів тому +2

      @@SabineHossenfelder would cryogenic temperatures slow down the effects enough so that they can be measured momentarily before collapsing into a state?

    • @Thomas-gk42
      @Thomas-gk42 26 днів тому +1

      @@seanmostert4213 I´ve heard, that Sabine peopose an experiment like that, 10years ago, that never was tested,...well, perhaps I misunderstood the connections.

    • @iyziejane
      @iyziejane 26 днів тому +7

      What you are describing is called a "hidden variable theory", the idea that quantum features such as the uncertainty principle or wave- mechanics could be caused by unknown hidden interactions. The uncertainty principle and wave functions are often taught to people in terms of a single particle. But a special quantum effect called entanglement occurs when you have more than one particle interacting. Entanglement is the part of quantum theory that can't be explained convincingly by hidden variables. Experiments with entanglement (e.g. Bell's inequality) force us to accept that something very strange happens at the quantum level. As Sabine says, "the trouble is to do it locally", she means that to explain the results of Bell's experiment, the hidden variables could not act "locally" when we perform measurements on entangled particles that are separated in space.

    • @Thomas-gk42
      @Thomas-gk42 26 днів тому +1

      @@iyziejane But what I know from her papers is that Sabine herself works on a hidden variables theory, sometimes called superdeterminsm.You have either to give up locality, what classical QM has done, or the postulate of statistical independence connecting the measurement outcome with the detector setting, what superdeterminism does. As I said, she made some experimental proposals to test it (similar to the first commenter), but none of them were implemented.

  • @fabriciotoscano7185
    @fabriciotoscano7185 26 днів тому +1

    Your approach to physics is the best ! Well done ! 👏🏾👏🏾👏🏾

  • @samedwards6683
    @samedwards6683 12 днів тому

    Thanks so much for creating and sharing this informative video. Great job. Keep it up.

  • @Infinite_Horizonsss
    @Infinite_Horizonsss 26 днів тому +4

    Thank you for the video 🎉

  • @hydewhyte4364
    @hydewhyte4364 26 днів тому +23

    This is why physicists throw the best parties.

    • @chris.hinsley
      @chris.hinsley 26 днів тому +4

      Not until we can come up with some system that makes all of Sabine’s clothes jump 3 feet to the left…

    • @MichaelWinter-ss6lx
      @MichaelWinter-ss6lx 26 днів тому +3

      The atoms of the clothes are to jump two feet to the left.

    • @chris.hinsley
      @chris.hinsley 26 днів тому +2

      @@MichaelWinter-ss6lx left or right the end result is okay with me.

    • @I.amthatrealJuan
      @I.amthatrealJuan 26 днів тому

      Like Hawking's time traveller party

    • @baomao7243
      @baomao7243 26 днів тому

      Hell raisers

  • @sabinrawr
    @sabinrawr 24 дні тому +1

    I've given a lot of thought to Many Worlds, but from a conceptual position rather than mathematical. I'm not convinced by it, but some interesting ideas emerged.
    Imagine my consciousness as a wave function. It can only perceive things whose waves are in-phase with mine. It's not that a particle is found to exist in different places in different separate universes, but that the particle is, and remains, in its superposition through measurement... but we only observe the position that is in-phase with ourselves.
    There are not infinitely many different versions of reality, just infinitely many different stories about it.
    We might even consider the possibility that inexplicable phenomena (like ghosts, the Mandela effect, or déjà vu) might be parts of this reality that are nearly in-phase but not quite.
    If true, it's interesting to think what might be possible if we could shift our own wave phase to experience a different version of reality that's more to our liking... maybe one without stinky feet!
    Edit to add this: if the universe is actually deterministic (think: block universe), it might be that the only part not yet determined is which "version" we will experience. Perhaps all possible versions already do exist in eternal superposition, but our experience will depend on how our consciousness evolves through our choices.

  • @b.munster2830
    @b.munster2830 25 днів тому +1

    I think it’s much simpler than some physicists do make believe.
    QM is a way to predict probabilities of measurement outcomes in the FUTURE. (This does not necessarily relate to future measurements themselves, but rather to future knowledge of the outcomes. For example, when Schrödinger’s cat is put in the box and the lid is closed, anything that happens to the cat is future knowledge for observers outside the box until the box is opened, while the cat itself is an observer inside the box who knows when the toxic gas is released).
    Indeed, all possible outcomes (which define many possible worlds) coexist at present. But possible outcomes are theoretical only, they are not real outcomes. Therefore, the many worlds are also theoretical only, i.e. not real. Only when the real outcomes are known, it becomes clear which of the many possible worlds has become reality.
    If the toxic gas is released in the box, the cat can know (e.g. smell) it earlier than outside observers.
    When a measurement outcome becomes a known fact (i.e. reality), that is the moment when the wave function (for future predictions) collapses. It’s really just like playing dice. The probability of throwing two sixes in a row is 1/36, but once the first six is thrown, we can rule out all other possibilities, and the probability of throwing a second six has collapsed to 1/6. There is nothing strange about that.
    The only case where QM is strange and doesn’t behave like playing dice, is in the correlation of entangled particles, even at great distances. I wish scientists could come up with a better explanation for that.

  • @MadridBarcelonaRota
    @MadridBarcelonaRota 27 днів тому +7

    But Sabine, our ability to observe with all our senses must always mean that we are continuously measuring everything we are aware of. To my mind we are only aware of what we are aware of. We cannot be aware of what we are not aware of so every thing we are aware of is in a state of being measured by ourselves. Thus the quantum field is continuously collapsed to what we have measured it to be. Happy to concede my measurements are not necessarily exactly coincident with yours.

    • @SabineHossenfelder
      @SabineHossenfelder  27 днів тому +3

      So how come that whenever two people compare what measurement results they have become aware of they find the same thing?

    • @luke7111
      @luke7111 27 днів тому

      ​@@SabineHossenfelder hi, idk if you could help me a scientific opinion on my lay man understanding
      isn't measurement just the observation we make with our brains?
      i don't understand why there's a question about it
      for example, if i smell something, my brain creates the 'understanding' of what im smelling
      if its something ive labelled - lets say cheese - i will recall that and refer to it that way.
      i've observed the small of cheese!
      the thing did not collapse into cheese from an undefined set of properties because i smelled it
      i were able to observe it as such because it already has been collasped to begin with
      kinda like from the beginning, the particles just ended up being cheese
      if another person does an observation they will come to the same conclusion
      same as in - their brains will take the process of recollection and labelling.
      if they labelled that smell as cheese before, they would do that and agree with me
      if somehow they were tricked to think cheese is called chocolate, they would say its chocolate and say their measurement is different
      its still 'cheese' in a way, but its also 'chocolate', so u could almost say the state collapsed differently for them
      but not because the 'thing' in question was in different undefined states - but rather that their own state wasn't the same as mine so relatively speaking, their view point or frame of reference prevented them from observing it the same way ive' had or something?
      uhh, kind of weird to write that makes my brain almost think that the whole super position stuff is just that is u have more than 2 things, 3+ - A B C, each thing looks at each other differently cause they cannot be in the exact same position at the same time
      like if i imagine a triangle of particles
      A - B
      \ /
      C
      each can only see the other in a very limited way, A only sees B's left side
      C see's B's left/bottom side
      B doesnt' see itself at all
      and if that applies to all particles in the universe at the same time, observing from any position relative to other gives a different result, but they are still A B and C; we just saw it from different perspective so it seems like they are different measurements, almost like particles changed based no how we looked, idk?
      in some human brain way they did 'change' but physically they haven't?
      they just 'interacted' (which is what observation is from like human perspective rigth) differently cuz of where im standing?
      tbf kind of fun being prompted to think too much from the video ha ha

    • @wb3904
      @wb3904 26 днів тому

      That's why you never see a quantum state directly. Every observation causes or is the result of a wave collapse.

    • @FalkFlak
      @FalkFlak 26 днів тому

      The question is, why would a consciousness measure anything else?
      Is there more than one MOST probable measurement?
      I know this borders on metaphysics but I find it absolutely unterstandable that the consciousness (tries to!!) only construct "measurements" that are in line with what every other conciousness would measure.
      So, for example every brain would measure a reality in which the big bang most likely would had happened even if it doesn't measured it in that instant because it's the only causal connection that works with every other particle in the universe. They all Connect to each other, I don't need to measure every single one of them.

    • @wb3904
      @wb3904 26 днів тому

      @@FalkFlak it's not consciousness itself. As I understand it, it's when a particle like a photon hits your eye it has a definite position and the wave function collapses, going to a single state.

  • @marcuscarana9240
    @marcuscarana9240 26 днів тому +7

    Standup comedian with a phd in theoretical physics:
    Population: Sabine

  • @milkibearmilkibear
    @milkibearmilkibear 24 дні тому

    Another amazing video, definitely going to read the paper, also than you for the brilliant discount!!! :)

  • @andreaoldofredi3436
    @andreaoldofredi3436 26 днів тому +1

    Sabine (if I may) your videos are excellent! Very clearly articulated, precise and easy to follow. A pleasure to watch!

  • @ronburk5135
    @ronburk5135 26 днів тому +6

    So in other words. It's turtles all the way down.

  • @ratedrmartian
    @ratedrmartian 26 днів тому +3

    Quantum mechanics is definitely weird but that's what I like about physics stuff I possibly couldn't know everything about it

  • @OrlandoRenato74
    @OrlandoRenato74 24 дні тому

    Love your Chanel Sabine....tus puntos de vistas siempre cuestionan muchas opciones de interpretación alternativas....Out of de box...saludos dese Peru❤

  • @Yezpahr
    @Yezpahr 26 днів тому +2

    The segue to the sponsor was measured as smooth to the touch.

  • @TerryBollinger
    @TerryBollinger 26 днів тому +5

    5:32 _"I am convinced that the next breakthrough in physics will come from figuring out just what a measurement is."_ Quantum observation is acceleration. No matter how minute - one photon is fine even for a large object - acceleration nudges a self-contained quantum system (particle or internally bound object) into a slightly different inertial frame. Observation is always a two-way business since acceleration converts a tiny bit of energy into an action-reaction momentum pair that establishes a mutual observation (knowledge) of each entity of the other.
    Most of the confusion on this issue comes from conflating two very different processes.
    The first process is energized transformation, such as converting an electron in its low-energy atomic orbital cloud form into an expanding waveform that we associate with an ejected particle, often dubiously at these small scales. That's about as quantum as emptying a puddle by pumping it out of a more localized squirting nozzle. You only get the desired transformation if you have enough energy.
    The second process is spacetime uncertainty collapse. This is the "true" quantum collapse, initiated by even the tiniest shift in the relativistic frame. You don't notice this much in condensed matter because atoms reside at the boundary of sufficiently rapid observation through small momentum exchanges - mostly phonons - to keep them fully localized relative to each other, thus keeping _space_ well-defined. Even if unknowingly, this is why Einstein was always keen on using physical rulers when setting up his thought problem coordinate systems.
    The tricky part of the second process - well, the other tricky part, since most folks don't like thinking of space and time as nothing more than local-only subsets of how the universe handles separation and change - is that the energy needed to fund spacetime uncertainty collapse can be so astronomically low that it becomes tempting to treat it as not existing at all - that is, to call it a "pure" wave function.
    Quantum cats die using the first process, energy transformation. This happens and is irreversible even if they stay out of touch with the universe for a while.
    Quantum cats end up _positioned_ within an observer's space using the second process of spacetime uncertainty collapse. They can still interfere through, say, an unusually large two-slit experiment, regardless of their dead-or-alive state. But extending this extremely narrow version of _location_ uncertainty to the cat's internal state is a serious modeling error.

    • @riveteye93
      @riveteye93 26 днів тому +2

      I'm very impressed that I almost understood what you wrote. I mean, thought I understood it, until someone will observe my mind it will remain a quantum mystery.

    • @TerryBollinger
      @TerryBollinger 26 днів тому

      ​@@riveteye93, thanks. First, I like your Ano Nymous handle. It's a pretty cool parsing of the word.
      The nice thing about acceleration as observation is it makes sense classically. After all, if someone bumps into you, you know where that person is, and they now know where you are. You have no clue where they are if they don't bump into you. What's remarkable is that _every_ case imaginable of quantum "collapse" involves at least a tiny, but always measurable, "bump" of some sort. Some of these, such as photons bouncing off of solar sails, are nothing _but_ tiny momentum bumps. Those don't fit well with quantum field theory. I would encourage anyone reading this to post an example to the contrary. If you think you have one, I'd love to hear it.
      The deeper question is why bumps are so important and how they can make such a remarkable difference on the scale of quantum wave functions. That is... fascinating but also a bit mind-bending. Our brains are not wired to think that way. You must reach into networking theory, like how the Internet keeps itself sane despite global delays in how fast information is traded.
      Here's an analogy that works upsettingly well: Acceleration is vital because until it happens, _each of us lives in our own isolated universe._ That's almost impossible in the classical world, and that's the point: All the constant jostling at every scale imaginable is what _keeps_ our world classical. The problem is that as you get smaller, your particle-sized universe quickly starts losing track of where it is within the larger universe, much like trying to walk with your eyes closed. Even worse, your tiny universe _expands_ as it loses track, making its final location even harder to figure out.
      We call that result a "wave function," but even that is not quite right. Like particles, waves are possible _only_ when defined to an existing coordinate system, such as a mirror or hologram. The word I've been using for the isolation that occurs without bumping is Sanscrit _nirakar_ ("near-a-car"), meaning unformed. This is the most promising approach mathematically, but it is very algorithmic. No points are allowed, for example, since those become unreachable, infinitely costly limits. So much for infinitely precise number lines! It's intriguing and likely much easier computationally by not overpresuming how much detail is needed to model a problem.
      Finally, the nice thing about acceleration collapse and the quantum state of your mind is that all you need to do to get your mind back in synch with the local universe is whack yourself on the side of the head... :)

  • @europaeuropa3673
    @europaeuropa3673 26 днів тому +4

    My mind keeps drifting toward mental instability, the more I try to accept quantum mechanics.

  • @user-Mike755
    @user-Mike755 25 днів тому +1

    Thank you Sabine!

  • @Nostrudoomus
    @Nostrudoomus 26 днів тому +1

    Thank you, Sabine!

  • @StabilisingGlobalTemperature
    @StabilisingGlobalTemperature 26 днів тому +24

    Just because we cannot measure something does not mean it does not exist. Falling trees in forests etc.

    • @chris.hinsley
      @chris.hinsley 26 днів тому +3

      Thing is when you end up in the wood chipper I think everyone’s going to be able to hear that.

    • @brothermine2292
      @brothermine2292 26 днів тому +4

      >chris.hinsley : If the wood-chipper is in space, no one can hear you scream.

    • @chris.hinsley
      @chris.hinsley 26 днів тому

      @@brothermine2292 you can feel the rumble through the decking plates though !!!

    • @collin4555
      @collin4555 26 днів тому

      Kind of fundamental to quantum theory, Heisenberg Uncertainty and all that

    • @Ciremo
      @Ciremo 26 днів тому +1

      Maybe it doesn't exist, regardless of if we can measure it or not.

  • @MartianSolarbuddy
    @MartianSolarbuddy 26 днів тому +2

    “Multiverse fanatics” 😂😂😂 You nailed the problem right there.

  • @eonasjohn
    @eonasjohn 26 днів тому +1

    Thank you for the video.

  • @neutronium_goes_wild
    @neutronium_goes_wild 23 дні тому

    the latest proposed hypothesis is the universe is basically a planck relic of a black hole [infinite virtual space], and it's quantum based
    that all means, the universe as a "quanta" is in superposition where all your decisions and measurements are constantly "transporting" you from one parallel reality to another one, you're basically browsing parallel realities based on your decisions since the universe is in all states at once

  • @carlbrenninkmeijer8925
    @carlbrenninkmeijer8925 27 днів тому +3

    A brilliant explanation, thanks a lot !! I also like your cat(s).

  • @lifeofgaurz
    @lifeofgaurz 26 днів тому +4

    The way you talk about complex topics is AMAZING

  • @nikbivation
    @nikbivation 26 днів тому

    wow amazing, thank you for this insight!

  • @LuisAldamiz
    @LuisAldamiz 26 днів тому +1

    I'm beginning to think that Heisenberg made it all up.
    Quantum is electrons interacting with photons in discrete packages (much as cups don't spill water until exactly the point of filling), all the rest seems a bit dubious.

  • @S.aTan-._.-
    @S.aTan-._.- 26 днів тому +195

    Shout out to all the unemployed still in bed

  • @qazsedcft2162
    @qazsedcft2162 26 днів тому +3

    Thanks Sabine for telling me I don't exist. 🤣

  • @HardcoreHokage-cw4uq
    @HardcoreHokage-cw4uq 26 днів тому +2

    Like the Greek philosopher Zeno who postulated the paradox before you can ever reach your destination, you must travel halfway there, always leaving another half. If there's always a smaller "half" to be taken, how could you ever arrive to the place you're headed?

  • @BenjaminCronce
    @BenjaminCronce 24 дні тому

    My natural assumption about quantum vs classical is that a set of entangled particles are themselves a measurement device and every time they interact with another set of participles, and become entangled, the entanglement causes the two previously independent quantum systems to become a single system. But there are ways to isolate particles into separate quantum systems, which is constantly happening, creating some amount of randomness. And what constitutes a system may be more of a continuum.

  • @GadZookz
    @GadZookz 26 днів тому +14

    People who truly believe reality doesn’t exist need to be observed by real people 24/7.

  • @andrewbouskill5444
    @andrewbouskill5444 26 днів тому +3

    Time is faster than light. Quantum mechanics describes the action of time.

    • @amihartz
      @amihartz 26 днів тому

      how can time have a speed? what does it even mean to assign a velocity to time?

    • @andrewbouskill5444
      @andrewbouskill5444 26 днів тому

      It means the rate at which reality occurs in the present moment is faster than light. It may be that on the quantum scale, where the tiniest of particles interact, causality can be broken. Take quantum tunneling, for instance, where the particle seems to break light speed once it trespasses the energy wall. Suppose the particle is taking a quantum pathway backward in time before the barrier was there in the first place and then jumping back to the present.

    • @amihartz
      @amihartz 26 днів тому

      @@andrewbouskill5444 How can you assign a speed to the "rate at which reality occurs" when speed is defined in terms of time? Linguistically it does not even make sense what you are writing. Light moves at about 300 km/s, the only way to say something can move "faster" than it is if you can also express its speed in terms of km/s (if you cannot, then it linguistically makes no sense to say it is "faster"). So what km/s does time move at? 450 km/s? 1000 km/s? If time moves at a speed defined in terms of km/s, then how is this not viciously circular given that part of the definition of its speed is itself?

  • @kxqe
    @kxqe 26 днів тому

    0:55 Actually a table is spread out in space and is in many places at once. If you cut the table into two pieces, they are entangled -- if you measure one piece, you know some of the properties of the other. However if you wait long enough, the table pieces will decohere into their constituent molecules and atoms and they will no long be entangled. Understanding QM from a classical perspective makes sense to me.

  • @Regalert
    @Regalert 26 днів тому +2

    I guess what changes with big objects (classical) and tiny ones (quantum) is speed: the tinniest the thing, the faster it moves. And velocity maybe be they "key" ("door") to olther dimensions. Another thing, our experience could be the interations of particles in interacting on different scales (speeds) , hence creating patterns (realities), as system...

  • @djayjp
    @djayjp 26 днів тому +17

    A "measurement" occurs anytime something becomes entangled with something else. Btw technically the MWI postulates a near-infinite multiverse, not infinite (though presumably future infinite).

    • @innocentsmith6091
      @innocentsmith6091 26 днів тому +3

      How is it only near infinite when wavefunctions are continuous? Shouldn't any real number position be possible?

    • @nightknight6947
      @nightknight6947 26 днів тому +1

      yes yes I see. vbery intereting all this. 7/5.

    • @absalomdraconis
      @absalomdraconis 26 днів тому +1

      ​@@innocentsmith6091: I'm not _certain_ what "presumably future infinite" in OP's post means, but I _suspect_ it means "constantly growing larger, and thus closer to infinite".

    • @thomasgoodwin2648
      @thomasgoodwin2648 26 днів тому +1

      At the singularity of the universe all energies are in a single wave state, no further entanglement needed. Does it observe itself?

    • @SabineHossenfelder
      @SabineHossenfelder  26 днів тому +31

      If a particle decays into two particles, that creates an entangled state, yet it's clearly not a measurement.

  • @osmosisjones4912
    @osmosisjones4912 26 днів тому +4

    Isn't the cat conscious

    • @nextlevelenglish5858
      @nextlevelenglish5858 26 днів тому +1

      yes, and you would need to do this in a vacuum, so it would die before the experiment

    • @TheMrCougarful
      @TheMrCougarful 26 днів тому

      We invented consciousness, and then abandoned it as a flawed idea.

    • @osmosisjones4912
      @osmosisjones4912 26 днів тому

      @@TheMrCougarful conscious invented US

  • @Mark8v29
    @Mark8v29 26 днів тому

    I enjoy the description of the measurement problem implied in the Futurama TV series.

  • @brendangolledge8312
    @brendangolledge8312 19 днів тому +1

    I thought a measurement was any interaction with a macroscopic body. In other words, any time a quantum particle is forced to interact, the wave function collapses. I was taught in my quantum mechanics course that when you have many particles together, there are overlapping parts of the wave function, and that these parts tend to cancel each other out, increasingly so when there are a large number of particles. Thus the state of an individual particle is uncertain, but the uncertainty in a macroscopic object as a whole becomes vanishingly small due to the large number of particles.

    • @lepidoptera9337
      @lepidoptera9337 11 днів тому +1

      A measurement is an irreversible energy exchange. It does not have to be a macroscopic body that captures this energy. Even the loss of energy towards infinity (e.g. escaping electromagnetic radiation) is "a measurement". Technically that's the only measurement we need in quantum field theory (outgoing plane waves) but since we are impatient we usually put a thick piece of matter in the way of that outgoing radiation and we give it a fancy name like "detector". :-)

  • @alieninmybeverage
    @alieninmybeverage 27 днів тому +13

    Out of all worlds, why did I get stuck in the one where people believe in many worlds?!

    • @nextlevelenglish5858
      @nextlevelenglish5858 26 днів тому +1

      and you can disprove it how?

    • @alieninmybeverage
      @alieninmybeverage 26 днів тому

      @nextlevelenglish5858 I certainly cannot. In fact, I apologize that this came across critically rather than tongue-in-cheek.
      I will say that I suspect that multiverse theories are the more the result of cynical rationale than naivety when it comes to the scientific/academic community. It appears to me an attempt to recreate the success of drake's equation in addressing the cross section necessary/sufficient conditions and elements we tend to intuit as "design" features that become enticing to rationalize as design/purposive if the universe is once-and-done, as if in response to evidence that the universe is not cyclical. It's a sort of "bayesian projection" onto the mystery.

  • @Nathan-vt1jz
    @Nathan-vt1jz 26 днів тому +5

    I think multiverse theories should be evaluated philosophically as it’s not positively testable or verifiable as a scientific theory.
    There’s nothing wrong with a philosophical theory or religious belief, they just are evaluated differently. We all have such beliefs/theories, we should just recognize the scientific method is limited in how it can address such topics.

    • @jimroth7927
      @jimroth7927 26 днів тому

      Some forms of "many worlds" might be testable. If we assume that each world has randomly assigned local physical laws independent of other worlds then, yes, not testable. On the other hand, if we assume that some universal laws of nature create all the worlds and determine the local laws of each world, then the universal laws might be discoverable and testable by observing the local laws in our world. I.E. The possible universal laws might be sufficiently limited by logical constraints and by local observations to rule out all but one set of universal laws.

    • @JeppeAchtonNielsen
      @JeppeAchtonNielsen 25 днів тому

      ​@@jimroth7927 My biggest objection to that is that we are already over interpolating our results. All of our experiments have been performed in a tiny solar system, which only represent a miniscule part of the assumed observable universe. Know you want to extend the interpolation further and describe multiple or even potentially infinite universes based on such a small sample size...
      Imagine for a moment the consequences if we discovered that several of our well established physical constants are in fact variable depending on location... and the only way to figure that out is to get of this tiny piece of dust and go somewhere else. We might just discover that several of our well established assumptions and interpretations are in fact completely wrong.
      Of course until we do that we are stuck with what we have, but can we please stop wasting time and energy on useless interpolations that can be tweaked infinitely to apply for more funding for theoretical physicists.

  • @Notsogoodguitarguy
    @Notsogoodguitarguy 25 днів тому +1

    Thank you, Sabine! You don't know if we exist, yet you still take the effort to explain things to us.

  • @michaelsherck5099
    @michaelsherck5099 26 днів тому +1

    The clarity of your explanations is enhanced by your sense of humor. Neither are expected of physicists with advanced degrees. If you did not exist it would be necessary to create you. 😉

  • @IzudeDarkwolf
    @IzudeDarkwolf 26 днів тому +3

    The main flaw I've found in quantum theories is misunderstanding of their tools and the limits of our observations. It's cherry-picked possibilities and ignoring the importance of falsification in the scientific method. We can't prove what is true, but we can prove what isn't. For example, superposition is likely a mathematical artifact from the planck scale, the physical limitation on our ability to quantize observations along with our common refusal to accept that every and any scientific "fact", that is appropriately called a theory, are educated guesses by recognizing patterns in correlations.

  • @DragoNate
    @DragoNate 26 днів тому +9

    physicists: "INFINITY COULD BE INFINITELY MORE INFINITE!"
    can we get these interested in videogames or something? they seem bored.

  • @mauriciogranados7833
    @mauriciogranados7833 26 днів тому +1

    The Mathematics NEVER LIE. The man every time does it.

  • @e-ric3052
    @e-ric3052 25 днів тому +1

    The Multiverse is a reasonable explanation of the missing sock conundrum.

  • @marcobiagini1878
    @marcobiagini1878 26 днів тому +7

    My name is Marco Biagini and I am a physicist; I want to explain the “observation” problem in quantum mechanics because it is often misunderstood even by many physicists.
    In quantum mechanics the state of a physical system is described by the wave function and does not have defined values ​​for all the physical quantities measurable on it; on the other hand, only the probability distributions relating to the measurable values ​​for these quantities are defined. Once the measurement has been carried out, the system will have a defined value in relation to the measured quantity, and this involves a radical modification of its wave function; in fact the wave function generally describes infinite possibilities while for an event to take place, it is necessary that the wave function assigns a probability of 100% to a single possibility and 0% probability to all the others. If all other results are not eliminated by imposing the collapse "by hand" on the wave function, the predictions of subsequent measurements on the same system will be wrong. The transition between a state that describes many possibilities to a state that describes only one possibility is called “collapse of the wave function”. The time evolution of the wave function is determined by Schrödinger's equation, but this equation never determines the collapse of the wave function, which instead is imposed by the physicist "by hand"; the collapse represents a violation of the Schrödinger equation, and the cause of the collapse is therefore attributable only to an agent not described by the Schrödinger equation itself. The open problem in quantum physics is that the cause of the transition between the indeterminate state and the determined state, cannot be traced back to any physical interaction, because all known physical interactions are already included in the Schrödinger's equation; in fact, the collapse of the wave function is a violation of the Schrodinger's equation, i.e. a violation of the most fundamental laws of physics and therefore the cause of the collapse cannot be determined by the same laws of physics, in particular, it cannot be determined by the interactions already included in the Schrodinger's equation.
    After one century of debates, the problem of measurement in quantum mechanics is still open and still represents the crucial problem for all interpretations of quantum mechanics. In fact, on the one hand it represents a violation of the Schrodinger equation, that is, a violation of the fundamental laws of physics. On the other hand, it is necessary for the laws of quantum physics to make sense, and to be applied in the interpretation and prediction of the phenomena we observe. Indeed, since the wave function represents infinite possibilities, without the collapse there would be no event; for there to be an event, then there must be one possibility that is actualized by canceling all other possibilities.
    This is the inescapable contradiction against which, all attempts to reconcile quantum physics with realism, break.
    Quantum mechanics does not describe reality as something that exists objectively at every instant, but as a collection of events isolated in time (i.e. the phenomena we observe at the very moment in which we observe them), while among these events there are only infinite possibilities and there is no continuity between events.
    In fact, the properties of a physical system are determined only after the collapse of the wave function; when the properties of the system are not yet determined, the system is not real, but only an idea, a hypothesis. Only when collapse occurs do properties become real because they take on a definite value. It makes no sense to assume that the system exists but its properties are indeterminate, because properties are an intrinsic aspect of the system itself; for example, there can be no triangle with indeterminate sides and no circle with indeterminate radius. Indeterminate properties means that properties do not exist which implies that the system itself does not exist; actually photons, electrons and quantum particles in general are just the name we give to some mathematical equations. The collapse represents the transition from infinite hypothetical possibilities to an actual event.
    Quantum mechanics is therefore incompatible with realism (that's why Einstein never accepted quantum mechanics); all alleged attempts to reconcile quantum mechanics with realism are flawed. The collapse of the wave function represents a non-physical event, since it violates the fundamental laws of physics, and can be associated with the only non-physical event we know of, consciousness. Therefore, events can only exist when consciousness is involved in the process. However, the fact that properties are created when a conscious mind observes the system in no way implies that it is the observer or his mind that creates those properties and causes the collapse; I regard this hypothesis as totally unreasonable (by the way, the universe is supposed to have existed even before the existence of humans). The point is that there must be a correlation between the existence of an event (associated to the collapse of the wave function =violation of the physical laws) and the interaction with a non-physical agent (the human mind); however, correlation does not mean causation because the concomitance of two events does not imply a causal link.
    No cause of collapse is necessary in an idealistic perspective, which assumes that there is no mind-independent physical reality and that physical reality exists as a concept in the mind of God that directly creates the phenomena we observe in our mind (any observed phenomenon is a mental experience) ; the collapse of the wave function is only a representation of God's act of creation in our mind of the observed phenomenon and is an element of the algorithm we have developed to make predictions and describe the phenomena we observe. This is essentially the view of the Irish philosopher George Berkeley, and in this view God is not only the Creator, but also the Sustainer of the universe. The fundamental aspect of quantum mechanics is that reality is not described as a continuum of events but as isolated events, and this is in perfect agreement with the idealistic view which presupposes that what we call "universe" is only the set of our sensory perceptions and that the idea that an external physical reality exists independently of the mind is only the product of our imagination; in other words, the universe is like a collective dream created by God in our mind. Idealism provides the only logically consistent interpretation of quantum mechanics, but most physicists do not accept idealism because it contradicts their personal beliefs, so they prefer an objectively wrong interpretation that gives them the illusion that quantum mechanics is compatible with realism.

    • @Thomas-gk42
      @Thomas-gk42 26 днів тому

      " Idealism provides the only logically consitent interpratation of quantum mechanics" -- that´s ideological pseudoscientific nonsense.

    • @minimal3734
      @minimal3734 26 днів тому +2

      Hello my friend, I'm a physicist too. I have been intrigued by these questions for a long time and came to the conclusion that there is no 'measurement' and that there is no 'collapse' of the wave function. These unfortunate ideas have solely been introduced because the group of physicists could not cope with the observations otherwise. Therefore the name 'Copenhagen' :)

    • @G3Kappa
      @G3Kappa 26 днів тому +1

      Isn't that just a very long-winded way to imply that the God of the Gaps is behind it all? It's not a satisfactory answer for a physicist. To me it just seems like a misguided conclusion that is impossible to prove and therefore not interesting or useful when it comes to describing the inner workings of reality. You can use that framework to claim anything and its opposite. That's just unscientific. The second you say something like "physical reality exists as a concept in the mind of God" you throw away all of your credibility, even if you're using big technical words to make your point.

    • @Thomas-gk42
      @Thomas-gk42 26 днів тому

      @@minimal3734 I think this is a bot, saw a similar comment some other times. But your interpretation of Denmark´s capital is funny. So you refer to a hidden variable´s theory?

    • @Thomas-gk42
      @Thomas-gk42 26 днів тому

      @@G3Kappa Entirely correct.

  • @frozenlettuce653
    @frozenlettuce653 26 днів тому +3

    "So you want to grant?"
    "Yes"
    "Well, I really wanto to give you, but I can't. Maybe in another universe!"

  • @paulbloemen7256
    @paulbloemen7256 26 днів тому +1

    As an interested layman to physics, and having a practical stance in the world: does my opinion count, is it relevant?
    With mathematics you can prove lots of things, about things you don’t know about, and about confirming the things you know about. The latter is usually utterly practical and useful.
    Let’s focus on the former: you prove something you don’t know about. In my view there are then two possibilities: what you have proven is either true, relevant to the world we live in, or false, irrelevant to the world we live in, but you don’t know which of the two. So you try and check what you found in the real world, there are three possibilities:
    - You find prove that your mathematics is true and relevant to the world we live in, you maybe found something new and exciting. Go and celebrate, and build upon these achievements.
    - You find prove that your mathematics is not true and relevant to the world we live in, your mathematics proved to be an interesting exercise that lead you nowhere, alas. Just let it rest.
    - You find no prove that your mathematics is either true or not true and relevant or irrelevant to the world we live in, in fact, you know as much after your efforts as before your efforts, namely nothing. Just try something else.
    As for those many worlds: there is no prove whatsoever of them existing, and their practical use for whichever endeavour is zero. The mathematics lead you to those possibilities mentioned above where it is wise to move on. Those physicists going on for years and years on these fruitless paths, in my opinion are becoming both a disgrace and a laughing stock, those sponsoring them should be ashamed about throwing money away that could be used in such a more useful way in our troublesome world.

  • @psychohist
    @psychohist 25 днів тому +1

    Observers are only necessary for quantum collapse. There's no quantum collapse in the Everett interpretation (MWI). Thus, "observer" is poorly defined, so no wonder there isn't a unique way to divide things into "observer" and "observed".

  • @michaelraine8111
    @michaelraine8111 26 днів тому +3

    I think a measurement is a decision point in an infinitely small moment of time so that our consciousness is continuously making measurements; because consciousness is doing this, it can never be measured!

  • @lotsofstuff9645
    @lotsofstuff9645 26 днів тому +95

    The “Many Worlds” interpretation feels a lot like a god argument. It just explains everything and at the same time explains nothing with an incredibly overly complex solution.

    • @valrond
      @valrond 26 днів тому +9

      Yep. That's what happens when science stops being science and becomes a religion. I

    • @philiphumphrey1548
      @philiphumphrey1548 26 днів тому +6

      Doesn't really make any unique predictions that we can test, either.

    • @lionelmessisburner7393
      @lionelmessisburner7393 26 днів тому +7

      It’s not like creationism at all lol

    • @marsovac
      @marsovac 26 днів тому +28

      I agree with the first part, but the solution is not overly complex. It is in fact the simplest solution possible. It makes exactly zero assumptions on the shroedinger equation. Something that you feel not satisfying does not make it overly complex. It just states "all outcomes to a measurement do exist". There are currently no simpler interpretations of QM, and perhaps can never be.

    • @firelordplayz
      @firelordplayz 26 днів тому +10

      It's actually nothing like it lol.

  • @alexandrascherer5463
    @alexandrascherer5463 25 днів тому +1

    On a molecular scale nothing is "flat" or "classical". "A measurement" is giving any degree of freedom extra energy to transform into another stable state - often returning to groundstate if possible under emission of something (concerning either vibration, rotation or by just mechanically stopping translation). There is no magic and nothing is at two places at "a" time (although the probability for two places is the same). It might be "at two places" within "a measurable time Intervall though".

  • @peregrinemccauley5010
    @peregrinemccauley5010 25 днів тому +1

    Sabine is well versed on this matter.

  • @ScottJPowers
    @ScottJPowers 26 днів тому +5

    quantum mechanics just gives you a range of possibilities given a lack of information. when you provide the rest of the information, it gives you a definite answer. This doesn't reflect the real world, however. just because you don't know something for sure doesn't mean that part of reality must be in some kind of quasi-limbo state, or do you all think that the world is an imagination of yours?

    • @Rudxain
      @Rudxain 26 днів тому +2

      There's a branch of philosophy that believes nothing is real except the self

    • @wb3904
      @wb3904 26 днів тому +4

      No quantum mechanics through the Heisenberg uncertainty principle says that it is impossible to know anything definitively. You can know the position or momentum of a particle but you can't know both exactly.
      So yes reality is in quasi-limbo state, something Einstein didn't like.

    • @ScottJPowers
      @ScottJPowers 26 днів тому

      @@wb3904 no. you can't know momentum and position at the same time because those two measurements are mutually exclusive. a position is 1 exact point in space but to measure momentum you need to know the difference in time when the particle was in at least 2 different positions at different times to measure velocity/acceleration. You'd need a third point of reference to know in what direction it is traveling. so, you can't say how fast something is moving or in what direction with only 1 point. Likewise, you can't say exactly where something is when traveling at a certain speed and/or a certain direction.

    • @wb3904
      @wb3904 25 днів тому

      @@ScottJPowers that's what I said lol. Read it again 😇
      Also it's not mutually exclusive, it's only that you can never get a full picture. It's like looking at a cube, you can only ever see 4 of the 6 sides.

    • @hal5189
      @hal5189 25 днів тому

      What I learned is, QM is not (as yet) the science of how the world works, but of what an observer can tell. By definition, "superposition" = "the observer knows that he doesn't know" and "collapse" = "the observer learns".
      That kicks out philosophy except "objective reality", and leaves scientific issues like "WTF is going on?". Except nobody seems to agree with this nowadays. Is there a reason it doesn't work?

  • @aaronjennings8385
    @aaronjennings8385 27 днів тому +4

    The double slit experiment seems like an example of a many worlds.

    • @wb3904
      @wb3904 26 днів тому +1

      No it shows that everything is a wave. If anything the collapse of waves into particles could be the spawning point of a new world.

  • @itwontbeTV
    @itwontbeTV 25 днів тому

    Sabine has this soft teaching approach when it comes to her quantum mechanic videos. Thank you Sabine!

  • @sergrojGrayFace
    @sergrojGrayFace 23 дні тому

    The Multiverse explanation of measurement as getting entangled with the measured thing makes the most sense.

  • @StylishHobo
    @StylishHobo 27 днів тому +24

    Many Worlds has always felt like fantasy rather than science. It's like a clumsy explanation a child would come up with.

    • @yeroca
      @yeroca 27 днів тому +5

      And yet some still feel that it is an inescapable conclusion. To me it doesn't follow Occam's Razor, but that isn't a good enough reason to reject the idea entirely. Maybe what these scientists are arguing is that the lack of a solution to the measurement problem is in fact a falsification of the idea of measurement at all, and that therefore the Copenhagen interpretation is ruled out. Perhaps this is just a false choice in favor of the many worlds interpretation. That said, I haven't attempted to read the paper.

    • @SabineHossenfelder
      @SabineHossenfelder  27 днів тому +13

      Does it really explain anything?

    • @Blokilicious
      @Blokilicious 26 днів тому +7

      It is the most sophisticated explanation for quantumn effects we have. It's simplicity lends weight to this. You really think our specific reality is the only form existence takes?

    • @Christian-gc6nn
      @Christian-gc6nn 26 днів тому +9

      ”It feels like fantasy” can also be said of many other strange things in science that has later been verified or proven false. Not saying many world is true but we shouldn’t rule it out for its strangeness.

    • @NoNameAtAll2
      @NoNameAtAll2 26 днів тому +2

      question is whether it's more clumpsy than alternatives
      and "quantum wave just magically decides where particle is" is just as obscene

  • @vishalmishra3046
    @vishalmishra3046 25 днів тому +1

    *Measurement* is just the *ENTANGLEMENT of the observer with the experiment* which therefore obviously leads to a single definite outcome within each logical universe as perceived by the observer in it.
    Quantum mechanics does not have any issues. It's the most popular (Copenhagen) interpretation that's blindly believed by too many popular physicists for decades that is the *real* problem. They think they are so special that Quantum mechanics does not apply to them (i.e. to the observers interacting with the measuring instruments). So no *COLLAPSE of Wave Function* is really necessary to explain the experimental results in any one of the logical universes.

  • @JeffMcGregor-zf7lf
    @JeffMcGregor-zf7lf 25 днів тому

    Seems like when they disagree with each other, it leads to them creating another virtual possible universe to resolve the dispute. Never leads them out of the Ivory Tower, they just go deeper into the abyss. Thank you Sabine for translating all the babble into coherent language and making it all understandable.

  • @RWin-fp5jn
    @RWin-fp5jn 24 дні тому +1

    The problem with physicists is that for 100 years they refuse to listen to what QP is saying. Their mindset is still glued to the classical view that our grid is defined by space (measure of distance) and time (measure of clock). They are still trying to express electron motion inside an atom in terms of space and time and never succeed. The only motion we DO observe is the quantum leap of electrons, where electrons move in orbit defined terms of eV’s (distance to nucleus) and mass (clock in the QP world). So they need to accept functions (Grid CLock Potential Inertia) and units (SPace time energy mass) have DUAL meaning. Measurement is nothing but the change of one dominant feature (e.g. enerry as grid) into the other (energy as potential), which entails in our outgoing light to cause or generate it. Simple…

  •  26 днів тому

    Nice video Sabine, I agree 100% with it

  • @rxbracho
    @rxbracho 26 днів тому +2

    You answered the question to the "riddle" when you said that the classical world doesn't come out of the MATH.
    Dear physicists: you must remember that math is a tool to understand what manifests in reality, which is what you are supposed to study.
    There is nothing magical about quantum mechanics but it doesn't talk about manifestation in reality UNTIL a whole is created, the smallest of which is an entangled pair (thus the emphasis on "observation").
    Keep on playing with math if you care, just don't confuse it with reality.

  • @JackdeDuCoeur
    @JackdeDuCoeur 26 днів тому +1

    What I most enjoy about science practice and its principal product, the scientific paper, is the vast territory comprising the space between the data and conclusions.

  • @madolite
    @madolite 25 днів тому +1

    Many Worlds 1.0: - "There's an infinite number of Universes."
    Many Worlds 2.0: - "No, actually there's an infinite number of an infinite number of Universes."
    Many Worlds 3.0: - "Hold my beer!"

  • @wareling
    @wareling 26 днів тому +1

    Damn, I love the way you slam it at 5:25 to 5:28😝 Excuse the pun … This channel is Brilliant

  • @kilianklaiber6367
    @kilianklaiber6367 26 днів тому +2

    Your videos are getting better and better. You appear to be ready for asking the hard questions and standing up against the crowd..., i.e. the "consensus".

  • @garymathis1042
    @garymathis1042 26 днів тому

    No physical "measurement" can perform a nonunitary transformation on a wave function, therefore no "measurement" can collapse a wavefunction. It's the observation of the measurement that collapses the wavefunction.

  • @gustavo_vanni
    @gustavo_vanni 26 днів тому

    @00:53 - Well, you got me, now what?

  • @leandrof.laurito887
    @leandrof.laurito887 21 день тому

    Hello from Brazil, i really like to watch your videos. :)

  • @DeGuerre
    @DeGuerre 25 днів тому +1

    I forget who it was who pointed out that quantum mechanics and relativity aren't hard to understand, they're just hard to believe.

  • @amohammed3337
    @amohammed3337 26 днів тому

    The Bhagavad Gita and Vedas speaks quite clearly of the existence of the multiverse. I find that quite facinating.

  • @oneeyejack2
    @oneeyejack2 26 днів тому

    there's two way in my mind that works to resolve the problem :
    - particle aren't wave like at all, but the void is packed with particle as half of them go back in time and perfectly cancels those who go forward.. so the sum of all this looks like QM statistically
    - particle are some sort of blob with a limited extension in the past and in multiple futurs.. so they slowly select between many worlds but some branch die constantly.. that way the number of alternate realities is a constant and what we call decoherence is the last common ancestor the current various realities..
    If you suppose there's a limit in alternate reality volume.. a measurement apparatus is a system that cause a quantum property to have macroscopic consequences... meaning "alternate values of a properties" cause "alternate macro group of particle to be different"... And in that case, it's easy to see that the value we observe could be the "last common ancestor" of alternate values of the property. If alternate values are link in space time in a tree way.. there can be relative to the observer multiple values each moment AND a single value of the past..
    A TREE OF VALUES OF CONSTANT WIDTH (in the dimension of alternates obviously!!) ALLOW FOR REALITY TO BE BLURED NOW and the PAST to be UNIQUE (the last ancestors of alternate realities). I've been screaming this for years and nobody listen.

  • @steverobbins4872
    @steverobbins4872 25 днів тому +1

    We don't need any more universes. We've already got so much universe, there's no place to put it all.

  • @guest_informant
    @guest_informant 25 днів тому +1

    I'm a Many Worlds fanatic. It seems to make total sense to me but it's a long way from any area of expertise I might have. I'd really like to hear Sabine debate this with Sean Carroll for instance - and hope that I could follow along.

  • @simonpayne7994
    @simonpayne7994 26 днів тому +1

    Sabine at her very best!

  • @thericster455
    @thericster455 25 днів тому +2

    It's that damned Infinity again!