Drum roll please… The 2022 Nobel Prize was given for the discovery that local realism actually does not exist. Who would have guessed it? Well, I know you guys certainly wouldn’t have! Haha, in your face!
It is a figure of speech. I was using the plural form of the word “you”, so that would be in everyone’s faces. You know who you are, so I won’t point any fingers. But, whoa, hold the horses there buddy. I wouldn’t go as far to say our reality is Rovellian. He gets a few mentions on the topic, but I don’t believe most physicists buy all the way into that camp. I would say it is consistent with the Copenhagen Interpretation. The idea is that more massive objects wave functions are negligible, so that can possibly separate them into being in a separate class to be able to be classified as observers. I believe that to be true, even though a test for that hasn’t ever been invented, yet.
I did not claim our reality is Rovellian. I asked whether the absence of local realism is consistent with the relational interpretation. It may be consistent with both relational and Copenhagen interpretations, after all.
Yes, I believe one argument against the Rovelli Interpretation is that you could never know the state of something without observing it. There is no way to know if a particle begins acting like a wave function again when you are not observing it. It would be equivalent to saying a unicorn and some fairies dropped in momentarily every time you looked away and no one was any wiser. It seems to add an unnecessary element to the situation. No one has ever observed a particle to begin acting more like a wave function. Observation makes the wave function collapse, so it seems as though it can only be a one way street where thing’s only happen the other way around. This transition would have to always have no after effect or influence on the particle. It makes it seem highly unlikely.
I don't get the "big news"? Local reality never was in quantum mechanics, right? That's what entanglement is all about (it isn't local reality). I'm no expert here (far from it) but what does this have to do with disproving the many worlds interpretation?
Most of the higher up positions in physics are filled with people that work on String Theory using the Many Worlds Interpretation, because it seemed more reasonable to adopt a more classical view where particles didn’t actually behave as though they were in multiple states at once. It gave them a more classical perspective on the idea, even though the Copenhagen Interpretation was shoved down all of their throats. They didn’t take well to it, so there is a generational gap there in our understanding of quantum mechanics. That was the top theory they where all working on. This experiment was long overdue, and the only people that held on to the old ways specialized in the field. They claim it provides the exact same results, but it really makes me wonder. Say, for instance, you run a quantum computer. They say that a spin up goes to one universe and a spin down goes to another universe using a qbit. But, what if you run two qbits? What universe would the microchip go to then? They are connected by a piece of silicon, so mechanically it is unfeasible in the many worlds. In the Copenhagen Interpretation the answer is simple. Both bits where just in a combination of both states, previously.
So you prefer the Copenhagen Interpretation, OK. The different interpretations are just a way to visualize what is going on.
I'm not sure this is an objection with any consequence. While it seems intuitively odd for a QM entity not to have definite properties in between interactions, it does not matter, since the only instances at which definite properties have consequence is in interactions. But I'm not really an apostle of relational QM. I just think it's an interesting idea.
That may be true. I have always been the kind of person that absolutely has to know the reason why. My mother use to get on to me and make fun of me for asking, why, too much. I never changed my ways on that, because I discovered that once you fully realize the reason why something is the way it is it can give you a big advantage over everyone else. You can then build on that idea to be able to achieve something greater, because without that insight you literally have no tools to work with to achieve anything in that regard. For all we know, one day Donald Trump or a future Donald Trump could hire one his lawyers to make him the head of the scientific field. He could say, well that is a really hand wavy idea and have it outcasted, fully outright, to be forever forgotten from the pages of history. The whole time it was spot on correct the entire time. Then one day the world is washed away by random fluke that occurs by a future society that has absolutely no idea how to fix the problem from becoming completely dependent on their own technology.
I recently read Rovelli's book (autographed copy!). His approach is interesting in that he tries to follow Heisenberg, who was inspired by Einstein's approach of throwing out all preconceptions and just starting from the observations and developing an approach that accounts for them. To do that, one thing he throws out is the notion that QM entities have defined values of properties that exist in a continuous manner in between interactions. He also says the wave function description of systems is not unique but depends on the informational reference frame of the observer. He thus accounts for Schrödinger's Cat by saying it is described by two different wave functions, one for observers outside the box, who describe it by a superposition of states, and a different one for the cat itself as observer, inside the box. It's an intriguing idea.
I have to admit that I had to look it up after you mentioned it, but it made me remember that it was an inspiration for me as well. I haven’t read his book, but I have read people that have mentioned about his ideas. They tried to dispute them. I ended up taking a different stance on the whole idea altogether. It sparked the idea in me that quantum mechanics may behave non locally due to the special theory of relativity. Then this idea was often shut down by the theory claiming a local speed of light limit. The idea is that a photon can assume that it is at rest. Then all of spacetime is contracted into a single point experiencing its entire world line at once, in one single instance of time. Then the theory can have a non local aspect to it. Then suddenly everything I read about quantum mechanics started to make reasonable sense by thinking about it in this way as being in a non local reality of its own. I believe that is the key in obtaining an understanding of it that could potentially begin to make it where someone could make accurate predictions with the absence of applying a rigorous mathematical formula to do the math. That is why I have a preset bias against his ideas. I don’t believe it will get us where we need to be where it isn’t just shut up and do the math.
I found it interesting that it was mentioned from the discovery of the equations guiding those principles of refraction implied that light somehow knew the future somehow to determine the fastest route to arrive at a location in the 1700’s, long before relativity was ever discovered. It is a common side note made textbook. It does resonate with the ongoing theme of some type of action at a distance taking place found in quantum mechanics. By taking the integral of all of the possible paths, the photon takes the path of least action to always make it arrive in the shortest amount of time. This value is said to be equal to zero in all branches in physics. I believe it really raises the question if it is actually equal to zero or if it can change to some other value. Then we have everything equaling a constant. My hypothesis is that it only appears to equal zero, because their is no presence of closed time like loops that exist in the system, but it could take on some other value if they did indeed exist.
My understanding of that is that it is nothing magical but simply that all longer paths interfere with one another destructively. In other words, it is a consequence of the wave nature of light. But I have not watched Hossenfelder's video.
You should watch it when you get the chance. It’s one of her better piece of works. She has a really dogmatic view on physics and it can make some of her videos really difficult to watch. I have heard that this is the belief of what the theory of everything actually is which is pushed by the educational system in Germany and nowhere else. It hasn’t gained much support for it outside of Germany. When you say that all the longer paths interfere with one another destructively, what have you done? You have essentially entered a nonlocal element to the description. Essentially, that is not wrong, and the experiment only confirms that can be an appropriate way to consider the situation.
I may do that. I rather like Sabine. And yes indeed, I suppose you are right that exploring all paths is a non-local idea.
