He is wooing the public a lot with a priest-like confidence on what the world is made of, look how amazing our 12 digit results are, everything is fields, even particles are really fields, even your bodies are fields, we can't really calculate this, it's so hard, but trust us. Matter, universe, big-bang, black holes, Faraday, Maxwell, Einstein, big scary equation, the single greatest equation, bombard and overwhelm the listeners with lots of astonishing statements and make them believe that we are really smart.
No experimental rationale for the reality of quantum fields; no mention of the opposing viewpoints of experts such as Schwinger (his source theory), also of large part of particle physics experimenters who tend to think that particles like electrons are real and quantum fields are really just tools that exist in our brains and on paper to predict what happens to these particles.
I am afraid this is not teaching people anything of value about physics. It's more about what this group of physicists (high energy theorists) are occupying themselves with.
However, I would say that most physicists do believe that quantum fields are the most basic building block of our world, so this isn’t some kind of pop science mess or even a mischaracterisation. Could it be the religion of physicists? Maybe. But it is a widespread one among experts.
Physicists generally consider their models to be real rather than just a mental idea that produces the correct results. This kind of thing was controversial in quantum theory until Bells theorem proved that quantum mechanics says things about reality itself (that it is either non local or non deterministic) and PBR theorem proved that the wavefunction is in some sense ontologically real. Now it is less controversial to say that quantum fields are real and the building block of reality
Scientists have grown less and less willing to make the ontological commitment. These days, if I ever see it, it shocks me.
That's why I'm so interested in this video. What has changed that would make a physicist so confident as to make these kinds of career-breaking ontological commitments?
The most excellent book I have read on the topic, and I highly recommend this to everyone on this thread: Arthur Fine "The Shaky Game: Einstein's Realism and the Quantum Theory". I would love to hear suggestions for books to read as follow-up to this.
I actually think it's the opposite. The PBR theorem even says that the wavefunction is ontological in some sense. People are more willing to make ontological commitments now than they were in the early days of quantum mechanics.
> career-breaking ontological commitments
It isn't career breaking at all. My boss is literally publishing a paper about how photons ontologically do not exist. Bell's inequalities and things like non-complementarity have a much stronger hold in people's minds due to modern tabletop uses of things like quantum correlations and EPR entanglement.
I basically disagree with the premise of your post. I am a postdoc in quantum optics, specialising in high-precision measurements and quantum measurement in general, and I think people are more willing than ever to choose ontological positions on QM.
I am very interested to learn more about any physicist who is willing to make ontological commitments. Ultimately, such a commitment is to realism - what is the epistemological support?
I strongly doubt the myriad complexities here have been resolved. Or are you proposing a kind of 'natural ontological attitude'?
If you think that physicists in general aren't working on these things you are probably confined within one subfield of physics. There are definitely thousands of physicists who spend a lot of time reading and writing papers on these kind of ontological topics
It's one thing to say, we're pretty sure A = B. It is another thing to say, we have definite knowledge that A = B. The epistemologers can be vicious gatekeepers!
To be clear, I want nothing more than to see a break in the log-jam of 20th-21st century epistemology. In fact, I am fighting for it. But I'm extremely skeptical that there is (or can be) any progress here, without a drastic and new approach. I am delighted to see brave physicists making ontological commitments - perhaps they are not aware of the tangled web that awaits them.
This is why Fine's book is called "The Shaky Game". Epistemological grounding for claims in physics is... shaky at best. I am not satisfied with Fine's concession - the NOA (natural ontological attitude). I believe that only a drastic solution will resolve it.
Please, please, please read Fine's book. It lays out the central problems here much better than I can hope to do, and is an pleasant and engaging read. And please stay in touch here and tell me what you think! I am practically obsessed with this topic, but I am not an academic, and have little time to research it.
The central binary here is 'realism' and 'irrealism'. In the simplest reduction, on one side, people say, 'this is what is REAL'; on the other, people say, 'prove it... psst, you can't'. Einstein was a realist, and was extensively ridiculed for it. I wouldn't be surprised if there are no actual ontological realists in physics today, though it is my sincere hope that there may be a few brave souls out there. I suspect that if you engage Tong (e.g.) in the deeper parts of this topic, he would eventually concede to a natural ontological attitude, and back off of the commitment.
I hope I am wrong!
It isn't that different from belief. It just seems better because it is based on a physical theory. It isn't about what is proven empirically but about what feels more likely based on the current empirical proof.
> "Whereof one cannot speak, thereof one must be silent"
I don't agree with that, and I don't think most people do.
> I am delighted to see brave physicists making ontological commitments - perhaps they are not aware of the tangled web that awaits them.
Remember that almost all physicists have no philosophy education, including those making ontological commitments.
> Please, please, please read Fine's book.
I probably won't, sorry. I am reading Marx and Hegel right now. Maybe in a decade or two.
> Einstein was a realist, and was extensively ridiculed for it.
I don't think so. A lot of people still think like Einstein or admire his commitment to a complete theory of reality. That's why we still have a lot of people interested in Bohmian mechanics.
> I wouldn't be surprised if there are no actual ontological realists in physics today
Most physicists are taught the Copenhagen interpretation with the first principle stated as "the wavefunction is the full physical state of the system".
> natural ontological attitude
I obviously don't know what that is
I think you are projecting a sense of philosophical expertise that is absolutely not present in modern physics. Again remember that almost all of us have literally zero training in any kind of philosophy. I am from the UK system, in the UK we do not study philosophy in high school, and at university we literally only do lectures that are directly related to our "major". I never did a non-physics lecture. The philosophical viewpoints of physicists is entirely based on a mixture of their pre-existing social conditions (whether or not they are religious) combined with their gut reaction to the physics.
A few points, with the hope that they are helpful, but bear in mind that I am also not an expert:
1. I too, disagree with Wittgenstein, though his statement is mostly logical in context. Disagreeing here is tricky.
2. Einstein was definitely a well-documented realist, and the debate is central to what I'm trying to get at here. I tend to defend him, though I suspect I am nearly alone among 'philosophers'. I think everyone else has jumped from what they see as the sinking ship of 'realism'. I suspect it is fully sunk at this point, except for a few die-hard realists out there. (Are there any left?)
3. The "natural ontological attitude" is a realist concession. It's basically what you are talking about, with some complexities for the interested. I like it, but it doesn't resolve anything, it just says, 'this epistemological nit-picking is annoying - I'm just saying that "it just seems better because it is based on a physical theory..."
My apologies for being pretentious or presumptuous about philosophical concepts. I just wish there were more open discussion of where these spheres overlap. Again, thank you for your critical thoughts here.
And truly, read the Fine book in a decade or whenever. It's amazing.
I would be interested in this paper. Lamb argued the same, with good intention, but not everybody was impressed.
EDIT: Also it of course references Lamb's paper, which I don't think was badly received afaik, just not really widely considered
I am afraid this is already the orthodox view, despite the suggestive/misleading pictures used when teaching particle physics (e.g. Compton's scattering).
But even the well-informed photon concept where a photon isn't a point, isn't a plane wave, and usually there is indefinite number of them, is quite horrible. I hope some day the status quo will move where we realize that both the hand wavy imprecise photon talk in textbooks/pop-sci books and the sophist "just a figure of speech when we're talking about quantum field" will be abandoned in favor of more accurate technical terms.
Do they? Maybe most theoretical physicists, because that's what they work with, they often are platonists and there is no better model. I doubt the rest, in particular experimental physicists, have even solid one or the other way opinion on this. Ontology is too much philosophy and too little physics.
Physics reports observations of experiments and theoretical work, but wisely leaves epistemology to philosophers - a hard learned lesson. Einstein was ridiculed for his ontological realism, and the trend has been in the opposite direction ever since.
I am interested in brave physicists who have stood up to the epistemologers, and are willing to make ontological commitments. In my understanding, historically, this attitude poses risks to one's career in physics.
I'm interested to talk to others who want to think about QFT past the maths. I had my own stab at making sense of related ontological implications here: http://www.katabane.com/mt/ontology.html#back8