Search FQXi


If you are aware of an interesting new academic paper (that has been published in a peer-reviewed journal or has appeared on the arXiv), a conference talk (at an official professional scientific meeting), an external blog post (by a professional scientist) or a news item (in the mainstream news media), which you think might make an interesting topic for an FQXi blog post, then please contact us at forums@fqxi.org with a link to the original source and a sentence about why you think that the work is worthy of discussion. Please note that we receive many such suggestions and while we endeavour to respond to them, we may not be able to reply to all suggestions.

Please also note that we do not accept unsolicited posts and we cannot review, or open new threads for, unsolicited articles or papers. Requests to review or post such materials will not be answered. If you have your own novel physics theory or model, which you would like to post for further discussion among then FQXi community, then please add them directly to the "Alternative Models of Reality" thread, or to the "Alternative Models of Cosmology" thread. Thank you.

Forum Home
Introduction
Terms of Use

Order posts by:
 chronological order
 most recent first

Posts by the author are highlighted in orange; posts by FQXi Members are highlighted in blue.

By using the FQXi Forum, you acknowledge reading and agree to abide by the Terms of Use

 RSS feed | RSS help
RECENT POSTS IN THIS TOPIC

Robert McEachern: on 3/26/17 at 19:04pm UTC, wrote "According to QBism, the wavefunction is no longer to be thought of as an...

Phil Hoffmann: on 2/15/17 at 6:17am UTC, wrote Taking a Bayesian stance to probability in QM is not new, and aligns with...

jim hughes: on 2/2/17 at 17:34pm UTC, wrote I think there's an independent reality. I only take issue with calling it...

Georgina Woodward: on 2/1/17 at 22:19pm UTC, wrote Re previous post, Feb. 1, 2017 @ 21:09 GMT: I should have said '....will...

Georgina Woodward: on 2/1/17 at 21:09pm UTC, wrote Denoting the outcome of the test of the first partner of the entangled pair...

Georgina Woodward: on 2/1/17 at 2:11am UTC, wrote Lawrence, my point: Two errors of thinking; 1. Entangled electrons have ...

Georgina Woodward: on 1/31/17 at 21:08pm UTC, wrote Anonymous, your proposed solution seems over complicated for the problem. A...

Anonymous: on 1/31/17 at 3:28am UTC, wrote It bears remembrance that it was Einstein himself whom first suggested that...



FQXi FORUM
April 30, 2017

ARTICLE: Painting a QBist Picture of Reality [back to article]
Bookmark and Share
Login or create account to post reply or comment.

Peter Morgan wrote on Jan. 23, 2017 @ 14:58 GMT
There's a nice rhetorical flourish to the idea that Bayesianism is a "more sophisticated interpretation of probabilities" (my emphasis). All I need to know now is whether sophistication makes something more or less likely to be Really True or, I suppose, inadequately to the sophistication of QBism, a Real Belief. Qualms about rhetoric aside, updating beliefs seems a sometimes worthwhile way to shut up and calculate, whether one commits to realism of any kind or not.

Question: is there any literature on how QBism applies to a QFT context?

report post as inappropriate


Joe Fisher wrote on Jan. 23, 2017 @ 15:59 GMT
Only nature could produce a reality so simple, a single cell amoeba could deal with it.

One real visible Universe must have only one reality. Simple natural reality has nothing to do with any abstract complex codswallop musings such as this utterly ridiculous article describes. No infinite visible part of surface could ever be in multiple invisible places at the same unnatural time. As I have thoughtfully pointed out in my brilliant essay, SCORE ONE FOR SIMPLICITY, the real Universe consists only of one unified visible infinite surface occurring in one infinite dimension, that am always illuminated by infinite non-surface light. Reality am not as complicated as theories of reality are.

Joe Fisher, Realist

report post as inappropriate


Lorraine Ford wrote on Jan. 23, 2017 @ 23:07 GMT
I think that QBism is the most coherent view of quantum phenomena, and reality, so far. Certainly, QBism’s view of quantum phenomena corresponds to our everyday perceptions (and the experimental results involving observers and quantum systems) that some parameters of our actions are free and that we can act and genuinely make a difference to the world. Opposed to QBism is the view that some parameters of our actions are random (e.g. as a result of our inhabiting a randomly selected multiverse outcome), or the view that all parameters of our actions are fully determined by the system of laws-of-nature, so that even though you might think that you are acting to make a difference to reality (e.g. because of climate change), all parameter numeric values now, and in the future, are already fully determined.

One thing that I’m not clear about is the issue of “locality”. If 3D space is due to relationship, as opposed to 3D space being a fundamental primitive of the universe-system, then law-of-nature relationships are the precursor to 3D space. If law-of-nature relationships are the precursor to 3D space, then it is possible for at least some law-of-nature relationships to be independent of 3D space.

report post as inappropriate


Steve Agnew wrote on Jan. 24, 2017 @ 04:44 GMT
Bayesian mechanics like all statistics have much allure because all observations when it comes right down to it are a matter of statistics. The real issue is the roles of the classical noise of chaos versus quantum phase noise.

The author does mention a nice product state (Eq. 13 in the cited paper), which looks like biphoton gravity, but Bayes is not quite up to gravity yet.

Just like the allure of the symmetry of the Standard Model, Bayesian statistics may simply be a complexification of the underlying simplicity of aethertime.

Good luck!

report post as inappropriate


Peter Warwick Morgan wrote on Jan. 24, 2017 @ 16:16 GMT
Having now read the Fuchs article that I didn't at first notice the link to, arXiv:1003.5209v1 [quant-ph], I noted that "A knee-jerk reaction in many physicists upon hearing these things is to declare that dimension as a capacity collapses to a triviality as soon as it is spoken. “All real-world systems possess infinite-dimensional Hilbert spaces. And it doesn’t take quantum field theory to be completely correct to make that true; a simple one-dimensional harmonic oscillator will do. It has an infinite-dimensional Hilbert space.”" I don't have precisely that reaction, but quite close. What seems in doubt to me is whether there is such a thing as a "real-world system", presumably isolated, or, if there is, whether such a thing has a determinate dimensionality except as an approximation or FAPP.

report post as inappropriate


jim h wrote on Jan. 24, 2017 @ 21:42 GMT
I'm seeing more and more buzz about QBism, but still no explanation of it that says anything to me. Ok, it's revolutionary, unorthodox, controversial. So are a lot of things. Per this article, the central insight is that "the outcome of a measurement can only be thought of as a new experience that the observer ought to take into account in any new beliefs." I guess I'd need a lot more than that, to even start getting interested.

So what is QBism?

report post as inappropriate

Georgina Woodward replied on Jan. 24, 2017 @ 23:58 GMT
Hi Jim, have you seen this srticle? A Private View of Quantum Reality Quantum theorist Christopher Fuchs explains how to solve the paradoxes of quantum mechanics. His price: physics gets personal. Amanda Gefter.2015 Quanta magazine

report post as inappropriate

Peter Morgan replied on Jan. 25, 2017 @ 15:33 GMT
Thanks for that link, Georgina. I quote from that article, amongst several other quotable Fuchsisms, "As QBism understands a quantum measurement outcome, it’s personal. No one else can see it." I see this quote as problematic as a description of experimental practice. In days of Bohr, indeed someone looked at a meter needle and no one else looked, but now it's almost universally a computer that...

view entire post


report post as inappropriate

Peter Warwick Morgan replied on Jan. 25, 2017 @ 16:23 GMT
Having now read the comments on the Quanta article you linked to, Georgina, just one comment there alludes to the qualm I express above, "There is an objective reality; it’s on a server somewhere. We each have our own copy to hack as we want. Why the quantum? Because pixels." At least, the first sentence, maybe the rest is too tongue in cheek, too little detail. One could say that an experiment only becomes part of science when it's published in a journal, ideally with supplementary datasets that allow the conclusions to be discussed in detail; then, it's on a server.

I also looked at a paper linked to by Blake Stacey there, https://arxiv.org/abs/1301.3274. The idea that QBism wants to take the KFC approach, that QBism's B stands for whatever I or you or Chris Fuchs says it stands for, falls rather by the wayside in the focus on SICs, more than hinted at at the end of the Quanta article. QSICism, hinting at "thus" or "just as", has a problematic sense. It doesn't have the same ring, but the mathematics, in contrast to the metaphysics, is kinda-maybe QPEism, Quantum Parameter Estimation-ism, allowing that one might use a Bayesian approach, but also allowing other statistical methods, when constructing Hilbert space models for experimental descriptions, which can be said to determine a prior before the experiment is run, and the resulting datasets.

report post as inappropriate


jim h wrote on Jan. 25, 2017 @ 04:18 GMT
Thanks Georgina, I'll read that article.

report post as inappropriate


Georgina Woodward wrote on Jan. 26, 2017 @ 20:46 GMT
Joe, I am deleting your posts because you are blanket posting the same message over and over again. I find your behaviour inconsiderate and tedious. I have tried discussing your ideas with you and have read and commented on your essay. You have not been ignored or had your idea suppressed. Your essay has been accepted for the contest and is available for anyone who is interested.Its just that enough is enough.

report post as inappropriate


Lawrence B. Crowell wrote on Jan. 26, 2017 @ 20:51 GMT
My feeling about Qbism is that it is in a long line of ideas about physics that leap off into philosophy. Quantum interpretations are all ways of trying to make metaphysical or existential categories fit with quantum mechanics. In general these fit into two sets ψ-ontology and ψ-epistemology. The big example of the first of these are the Everett-DeWitt Many Worlds Interpretation,. While less...

view entire post


report post as inappropriate

Georgina Woodward replied on Jan. 26, 2017 @ 21:38 GMT
Lawrence -never is very definite. Would you rather there was no discussion and no new thoughts on the matter? As there are already bunnies galore and no clear winner.

report post as inappropriate

Lawrence B. Crowell replied on Jan. 28, 2017 @ 01:04 GMT
Never, it is I suppose my bet, though I am not sure what Bayesian prior estimate to put on it ;-) As I see it quantum mechanics is of a physical nature that will always fail to conform to the brain's processing of reality. We would need a quantum brain! I might amend never once in the future we have cyber-neural connection (brains becoming a major set of hubs on the internet) and with that we start connecting quantum computers to brains.

Would I prefer that people stop wasting time on quantum interpretations? No not really, and some of them are useful. Even Penrose's interpretation, which is related to the Montevideo interpretation, is useful in some ways. Also, the more people spend on quantum interpretations that takes competitors off the game of doing real physics.

report post as inappropriate

Georgina Woodward replied on Jan. 28, 2017 @ 10:15 GMT
Lawrence,

what is the game of doing real physics?

report post as inappropriate


Joe Fisher wrote on Jan. 28, 2017 @ 17:04 GMT
Dear Georgina,

There must only be one real observable Universe. The question is whether reality is simple and self evident, or if reality is complex, elusive, and only scientifically verifiable. I have proven without a doubt that The real Universe must consist only of one unified visible infinite physical surface occurring in one infinite dimension, that am always illuminated by infinite non-surface light.

Your unrealistic considering of my truth being inappropriate does not alter it. It confirms it dear.

Joe Fisher, Realist

report post as inappropriate

Georgina Woodward replied on Jan. 28, 2017 @ 21:06 GMT
Joe, I made it perfectly clear that it is your inconsiderate tedious behaviour that is inappropriate.

Why not add convincing arguments and research, and reconsideration of the replies you have given on your essay page, where it would be appropriate. Some suggestions: Surfaces are not one dimensional. I would be interested to know more about the infinite eye you mentioned and where the eyes of bacteria are located.

report post as inappropriate

Joe Fisher replied on Jan. 29, 2017 @ 15:52 GMT
Dear Georgina,

Simplicity cannot be simplified. Nature must have provided a reality that all creatures could be capable of dealing with. As all of the creatures I have seen have eyes, in order for all creatures to be able to deal with simple natural reality, it am not too outlandish to assume that germs, bacterium and viruses must have some sort of eyes.

You will be pleased to know that my essay, THE SIMPLEST UNIVERSE am being reviewed by certified physicists.

Peace,

Joe Fisher, Realist

report post as inappropriate

Georgina Woodward replied on Jan. 29, 2017 @ 22:08 GMT
Joe my message was ambiguous. I intended to mean -put your comments on your essay page!

Your reply to me is significantly different from one of your replies over on that page where you wrote : "A physical eye must be infinite in size and number. I know that every cell, germ and bacterium must have eyes because of natural consistency. A dimension am not linear."Joe Fisher.

So if your point of view has changed it is important to update your page so that people can know what you think now.

report post as inappropriate


Anonymous wrote on Jan. 31, 2017 @ 03:28 GMT
It bears remembrance that it was Einstein himself whom first suggested that there may be a hidden variable which would allow that two particles at a distance could both respond as if there is a rigid spacetime connection directly between the two. It is QM in its axiomatic regime of absolute seperateness of any events which makes 'entanglement' spooky. And rather than hidden, the correct question...

view entire post


report post as inappropriate

Georgina Woodward replied on Jan. 31, 2017 @ 21:08 GMT
Anonymous, your proposed solution seems over complicated for the problem. A hidden variable is unnecessary, (so is superluminal communication). Entangled electrons are different from random electrons. The random electrons meeting Stern Gerlach apparatus for the first time act as if they have no state giving a prior preference for outcome. The "entangled" electrons with specific different states are not going to suddenly become ones without or switch to being the same as each other. Its like two bowlers, one throwing a ball with spin , one throwing a ball with backspin. Whichever is which the outcomes on impact are going to be related to the spin the ball was given. There won't be something strange happening with the momentum of the ball that causes it to change its motion from spin to back spin (or vice versa), or no spin, mid flight - risking a matching of outcomes. That is about conservation of energy.

report post as inappropriate


Phil Hoffmann wrote on Feb. 15, 2017 @ 06:17 GMT
Taking a Bayesian stance to probability in QM is not new, and aligns with the view that subjectivity is baked into QM. But "participatory realism" sounds like an oxymoron, or at least like wanting to have your cake and eat it, too.

Phil

report post as inappropriate


Robert H McEachern wrote on Mar. 26, 2017 @ 19:04 GMT
"According to QBism, the wavefunction is no longer to be thought of as an objective measure of the probability of getting an outcome of a quantum experiment that two observers will necessarily both agree upon."

The wavefunction corresponds to probability (the Born Rule), precisely because squaring a Fourier Transform yields a "power spectrum"; accumulated energy per bin. Hence, when the energy arrives in discrete, equal amounts (quanta), then the accumulated-energy within each bin, divided by the quanta, yields the number of quanta per bin. In other words, it is a histogram (being inferred from a measured power spectrum), which is why the whole process yields probability estimates.

Rob McEachern

report post as inappropriate


Login or create account to post reply or comment.

Please enter your e-mail address:
Note: Joining the FQXi mailing list does not give you a login account or constitute membership in the organization.