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

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.”

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

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

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.

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 RU-vid) 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.

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

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

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

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

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

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

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

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

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

“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

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

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.

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

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.

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

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.

This is why physicists throw the best parties.

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

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

Thank you for the video 🎉

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.

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

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

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.

Shout out to all the unemployed still in bed

Thank you Sabine!

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".

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

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.

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

Thank you, Sabine!

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

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

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.

wow amazing, thank you for this insight!

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

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.

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

Thank you for the video.

The way you talk about complex topics is AMAZING

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

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

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.

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

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

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

Since *I* am the only measurement device, I look forward to one of the results of the research you mention when I decide to look at it.

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

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

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

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.

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

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

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.

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

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.

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).

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...

I love your precise understanding of the philosophical problem of postulating as many realities as possibilities because maths only cannot distinguish among them!

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!

Isn't the cat conscious

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?

Sabine is well versed on this matter.

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.

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.

I'd wish to hear more about QFT from Sabine's videos. I'd find it inspiring, I'm sure.

Nice video Sabine, I agree 100% with it

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.

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

Fascinating! Thanks, Sabine!!! 😊 Stay safe there with your family! 🖖😊 (In some other universe I'm that cat, I'm sure of it. 😬)

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.

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

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?

Thank you. You have a finely honed sense of awareness. As a body sense aren't you bound to the quantum world? They seem to work together pretty well. Thanks again.

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

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

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. 😉

Excellent as always sabine, have you ever done stand up? It's thought if this science thing doesn't work out.

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.

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

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.

You make very good points about reality. One of my pet peeves is when I hear some scientists say that the direction (or arrow) of time is an illusion. The have the hubris to say this because their sub-atomic particle equations don't show it. However in my world (and theirs) time definitely has a direction. We could not live our lives without constantly taking it into account. Without it we are lost.

Sabine, I "feel" that you are still on the right track, knowing that I have no independant apparatus that produces a result to verify my feeling. Keep it up, stinky feet and all!

When it comes to observable phenomena, it's the required points of attention (as applied by math) required in order to decohere the state of this phenomena from its chaotic state into its equivalent order and form. (Given ones point of view with regard to dimension.)

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.

This puts me in mind of a differential equation whose general solution is a linear sum of different terms, one of which diverges at a physical position (typically at the origin). The standard approach is to set its coefficient to zero as it is non-physical and leave it there. Now I see that the divergent term exists in another universe.

Thank you for another excellent video, Sabine! Can you dedicate a video to the "bare theory" (David Z Albert, Jeffrey A Barrett), which is essentially von Neumann-Dirac quantum mechanics without any need for the (scientifically problematic) definition of what an "observer" is and no collapse of the wave function, ever? I mention this here because this interpretation makes the same predictions as quantum mechanics, but doesn't use the measurement hypothesis, and therefore has no need for a definition of what a measurement is. (It solves the definiteness problem by saying that definiteness doesn't exist in the universe, but we, our measurement devices, our environment, etc., all get entangled together, so from the perspective of any instantiation of the wave function for us there is also only one instantiation of the wave function for the measurement devices and the environment. Hence, no collapse, but rather a tendency towards diagonalisation of the overall probability matrix to its eigenvalues. This is often confused with the multiple worlds interpretation but the two are completely distinct.)

Thank you for showing an example of "twiddling thumbs" @2:39 so that some of us know what you mean

Sorry for an unrelated (or at least distantly related question): The link at bottom points to work being done in Bonn. It’s cellular imaging with machine learning. On one hand, I think it shows we are still too far from the molecules to see what is going on with electrons, but it’s close. On the other hand, it seems to go in the right direction. Thirdly, this reminds me of your video about academia and I’m wondering of something is changing. This feels like “tech bro” meets “grant writing software” and hires desperate post docs. Like an academic startup…? …what??? Link: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-fxg71kVFFO4.htmlsi=rQdnUiQlGk2jQPRw

I thought that classical was the limit of quantum once you understand that noise approaches the central limit? This is kind of like the definition of annealing an entangled system.

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.

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".

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".

This all goes over my head, but can it not be that each particle in the universe is actively measuring it's neighbors? It always seemed to me that we imbue life with too much credit as the "observer". Maybe the universe observes itself.

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.