theory salon

vzn

3:13 AM

7500 faceless coders paid in bitcoin built a hedge funds brain / wired

vzn

5:03 AM

dotwave.org

@ThomasKlimpel ↑ just found this, very comprehensive/ amazing, had to share it with someone! o_O

Thomas Klimpel

10:56 AM

@vzn Well, if I should chat about QM, I should better join your conversation with heather. But I'm still trying to finish this "information is energy" book, which uses QM in normal handwaving mode. By information, the author means his definition of dynamic information, which is something like information(flow) per time. Higher energy is normally associated with shorter times. What is good about this book is that it really discusses the time dynamics, which is otherwise often neglected.

vzn

4:20 PM

@ThomasKlimpel hope that book gets translated into english. yeah universe/ physics/ QM as information flow is an emerging/ trendy paradigm. seems to originate partly with wheeler "it from bit" although goes all the way back to fredkin. have another book on that espousing the view, trying to remember who wrote it, need to go back & dig it up. en.wikipedia.org/wiki/…

Thomas Klimpel

7:20 PM

@vzn That book itself will most probably not be translated into English. It is much too German for that, with too open ended tangential discussions, too honest discussions of points still unclear to the author itself, too many uncommented quotes by other people. But the concept of dynamic information itself might make it into "normal" physics publications some day. And it is probably not the type of book you hope for. But at least it is short and readable, that is why I decided to read it.

vzn

@ThomasKlimpel ACM & DS are ganging up/ "tag teaming" on me in Physics against hydrodynamics revolution so have to retreat anyway :|

Thomas Klimpel

@vzn You mean you intentionally annoyed them, and now they decided to do something about it?

vzn

@ThomasKlimpel (who me, intentionally annoy someone?) apparently just the std/ typical/ unchanged/ semithinking "shoot the messenger" knee-jerk reactionary stance, nothing more

Thomas Klimpel

@vzn Do you like the "hydrodynamics revolution" for its fluid dynamic parts, or for it analogies with quantum mechanics? Do you think that those analogies will lead to fundamental changes to quantum mechanics?

vzn

@ThomasKlimpel likely like it for the same reason you were searching for alternatives to QM dogma. (long ago, do you still remember that?) ... its the einstein (...de broglie/ schroedinger/ bohm/ bell/ 't hooft et al etc) objection totally/ unequivocally vindicated.

Thomas Klimpel

7:30 PM

(You know better than me whether you tried to annoy somebody or not. From my own experiences with physistics, they are very friendly people that are not easily annoyed, but they can be very stubborn about certain things such that you might be tempted to try to annoy them.)

vzn

@ThomasKlimpel they are not (much) interested in any new theories, they are to a large degree trained to reject them, the site is not good for it, you helped me with those boundaries long back with "nonmainstream physics" ban etc. ... have to choose battles wisely... & keep in mind its a marathon not a sprint. short run vs long run.

> there are those that make things happen, those that watch things happen, and those that wonder what happened.

am reading Bushs 2015 survey at this moment & looking for ammunition & not finding a lot, hes still very conservative :|

> It was over 30 years before Bell (1966) discredited von Neumann’s and subsequent impossibility proofs. On such matters, I am inclined to give Bell (1987) the final word, to entertain the possibility of a real quantum dynamics underlying the wellestablished statistical theory. It is then only natural to ask what relation this hydrodynamic system might have to existing realist models of quantum dynamics.

Thomas Klimpel

@vzn I know, my profile says: "For a long time, I wanted to understand quantum mechanics. Then I grew older and learned other things which are badly counterintuitive. I also learned that the Copenhagen interpretation is no longer the last word, which I find quite comforting."

vzn

@ThomasKlimpel think the doubters are often motivated by groupthink that can be changed by authority figures. they just havent seen "big enough" authority figures espouse the theory yet. (think even wild contrarian 't hooft was quoted as dubious of hydrodynamics.)

Thomas Klimpel

@vzn Is the dubious thing about QM really related to those hydrodynamics experiments? Isn't the exponential size of the Hilbert Space (i.e. the tensor product construction) the really doubtful part, which get exposed so brilliantly in the many world intepretation? If QM really has this huge processing power, then I don't really care whether it is achieved by an underlying hydrodynamics model, or by magic.

vzn

@ThomasKlimpel actually was just amused that bush adheres to MWI at the end of his long analysis! am defn not a fan of MWI. but think hydrodynamics does reveal some of the computational aspects/ explain some of the mystery. fluid dynamics is very expensive computationally. it also might be nearly a proof that nothing fundamentally "un/anti-classical" is happening in QM, ie BQP=P.

Thomas Klimpel

7:47 PM

Schmidt decomposition

In linear algebra, the Schmidt decomposition (named after its originator Erhard Schmidt) refers to a particular way of expressing a vector in the tensor product of two inner product spaces. It has numerous applications in quantum information theory, for example in entanglement characterization and in state purification, and plasticity. == Theorem == Let H 1 {\displaystyle H_{1}} and H 2 {\displaystyle H_{2...

@vzn To be honest, I don't know how deep the adherents of the many world interpretation dive into the related mathematics. The Schmidt decomposition only works for bipartite systems, and this is exactly the point where potential questions for the many world interpretation should arise. I can look at the world bottom up, and start with observing the "quantum experiment" vs. the rest of the world. Or I can look top down, and "trace out" the rest of the world first.

vzn

@ThomasKlimpel MWI has no unique mathematics afaik. think thats part of its (non)allure.

Thomas Klimpel

Well, I was a bit unclear. I think about the typical setup for QM interpretation, i.e. a relatively isolated quantum experiment, an observer (or laboratory) and the rest of the world. I could start the decomposition with the "quantum experiment" and the rest (i.e. the observer and the rest of the world). This will spilt the world. And then I could do the decomposition between observer(+quantum experiment) and the rest of the world.

The other way is to start with the rest of the world (either do the Schmidt decomposition, or trace it out to get a density matrix and the do an eigen-decomposition of the density matrix ... both are basically equivalent). And then I could do the decomposition between the "quantum experiment" and the "observer" (ignoring the rest of the world, because it has already been traced out). I have the impression that the MWI only looks at the bottom up approach, and never wonders about how it would ...

... compare to the top-down approach. What is strange about this Schmidt decomposition approach is that it generates a preferred basis for the different spaces, but the order of the decisions seems to have some impact on the actual decompositions.

vzn

9:08 PM

@Thomas it seems to be a mathematical discriminant for separable vs entangled states. definitely one of the big mysteries/ cruxes of qm noticed by Bell, still being investigated...

Thomas Klimpel

9:26 PM

@vzn Is it really "still being investigated"? And I think it is not just a mathematical question. When Luboš Motl, Arnold Neumaier, and many other present quantum mechanics based on the density matrix, they are effectively starting with first tracing out the rest of the universe. This is how I would also start, because I will never be able to obtain that information about the rest of the universe. But if I already started top-down for good reasons, why not just continue top-down?

But the spitting of the universe should be dependent on the result of the quantum experiment. Hence I want to go bottom-up for the many world interpretation. But if I already have to go bottom-up, why not just start bottom-up too, pretent that the universe is just one global wavefunction, and then continue bottom-up? Indeed, the only problem is that the two approaches somehow don't give the same splitting of the universe.

vzn

@ThomasKlimpel there is a better understanding of entanglement vs separability 1st analyzed mathematically by bell & it seems to be under active investigation. have not followed it closely myself but have seen it in scattered papers..

@ThomasKlimpel lol thought you were not into MWI either...

the reference to "observer vs observed" is starting to remind me of a similar dichotomy puzzled over for millenia in buddhism... which even apparently caused schisms/ school splits in the official doctrine somewhat similar to protestantism vs catholicism...

vzn

10:02 PM

further thought: its important to realize the so-called hydrodynamic interpretation is much more than merely that, its a picture, and a way forward & in this way is not indistinguishable from other interpretations (like MWI), but superior... ie in short its more complete/ real...

arbolverde

11:34 PM

hi

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