Saying I don't understand Quantum Mechanics is like saying, "I don't understand how attention/transformers explain the human brain."
It doesn't. It's model. All models are wrong (including quantum mechanics and attention) but some are useful. You understand the domain of the model, the problems it can solve, the math behind the models and use the model to make predictions. If you are competent at linear algebra and functional analysis, you can do quantum mechanics.
If you make the error of believing that quantum mechanics is ontological god's honest truth of nature, you will end up with blunders like using it to explain consciousness like Prof Penrose. His math was impeccable, but he was making a category error.
Don't take the title too literally. It's an article aimed at lay people, using a typical lay person's expression as the title.
The trick to a top HN comment is to basically reflexively react to the title with no regard for the substance of the relevant article. Amusingly, pointing out this self-evident truth is itself frowned upon and more offensive than the described trick, according to the sacred text.
I disagree. The human brain is difficult to understand due to the extreme complexity. Quantum mechanics is weird even for simple arrangements of a few building blocks such as the double-slit experiment or Bell tests.
Are you implying that on a basic level or for simple arrangements transformers do explain what happens in the brain? If so, I would be curious to hear how.
Quantum physics is a theory, as in "as far as we can tell, this is an exact mathematical description of the world".
Models are simplifications/approximations made on purpose, as in "I know this is wrong on some level, but it's close enough for my use case", or "this makes the maths solvable".
As someone with a degree in physics and math, I find the line you're trying to draw rather blurry.
> Quantum physics is a theory, as in "as far as we can tell, this is an exact mathematical description of the world".
Is it?
If by "mathematical exactness" you merely mean we have somehow been able to produce some numbers that later on we measured in experiments, then yes. (Though we haven't been able to produce such numbers in all cases, see e.g. [0].)
I my book, though, mathematical exactness means your model is mathematically consistent and is applied with the necessary mathematical rigor.
Quantum mechanics and quantum field theory, as they are commonly taught in universities, are everything but. They are a bunch of concepts and recipes that, albeit successful, are held together loosely with duct tape and lots of hand waving to make you ignore the logical gaps & jumps and the fact that many of the "mathematical" objects physicists refer to don't even exist[1]!
[0]: https://www.scientificamerican.com/article/this-simple-exper...
[1]: Haag's Theorem, Aizenman–Fröhlich Triviality Theorem, etc.
I’m not sure most physicists would make that specific distinction between "theory" and "model". We know QM is wrong or at the very least incomplete as long as there’s no theory of quantum gravity. Every theory, like every model, has a domain of applicability and gives wrong or even nonsensical answers when applied outside its domain.
What a theory is, is more like a model (or maybe meta-model) with a particularly broad scope or high explanatory value, often a mathematical framework that gives a common foundation and theoretical justification for multiple experimentally-derived models.
This is really a misunderstanding of what quantum mechanics is. It's not a particular theory. It's a category of theories that fit into a certain framework.
Quantum electrodynamics is a quantum theory. Quantum chromodynamics is a quantum theory. String theory is a quantum theory. I'm sure there is a correct quantum theory of gravity - we just don't know what it is yet.
This is an important distinction. Quantum mechanics as a framework is the correct description of reality as far as we can measure (excluding some loopholes like superdeterminism). This is as close to the foundation or "god" or whatever you want to call it as it gets. If you look at specific quantum model descriptions (like the Schrödinger equation), we know they are not complete. Even relativistically correct Dirac equation is still not the full picture, because we don't fully understand how gravity fits into this on short length scales. But the current principles like Bell's theorem exist independently with all their implications on our reality and they will not go away, no matter what else we discover at the bottom.
>>>Quantum physics is a theory, as in "as far as we can tell, this is an exact mathematical description of the world".
... which "we think" is functioning that way not to mention that theory itself might be wrong and be replaced as most of the supporters of quantum theory doesn't seem to look on it as something that explain mechanics of it, but rather how magic of "unexplainable" quantum mechanics works.
Eh I would disagree on such a sharp distinction. Both quantum mechanics and general relativity are theories, and we know that both of them are not accurate descriptions at all scales.
Heck your descriptions of a model is also what we would call an effective theory (i.e. a description valid for a specific range of parameters/scale).
I don't think there's a commonly agreed difference between model and theory and I sure have heard many physicists use them interchangeably when it suits them (and I'm guilty of it myself). Perhaps theory feels 'wider', as in quantum theory encompasses models for many quantum systems, but that's as far as I'd go.
It all reminds me of my favorite Asimov quote:
> [...] when people thought the Earth was flat, they were wrong. When people thought the Earth was spherical, they were wrong. But if you think that thinking the Earth is spherical is just as wrong as thinking the Earth is flat, then your view is wronger than both of them put together.
Yes, but even with a model, you should aim for some serious intuition as to how and why it works.
Penrose has fallen into the same logical fallacy that many older, retired theoretical physicists have (notable einstein?).
> It doesn't. It's model. All models are wrong (including quantum mechanics and attention) but some are useful.
Sure, but what if you don’t understand the model?
Somehow hacker news makes the top comment about some weird unrelated ai take. So unrelated. The take mostly doesn't make sense either.
There are only a few things that I think are exactly correct in physics, and quantum mechanics is one of them, alongside Relativity.
Quantum mechanics is a framework for how theories are built, not a specific theory, and it's really all or nothing. There's not much between the quantum and classical ways of viewing the world.
Both cannot be “exactly correct” at the same time. And most likely, neither are.
Indeed. The classical view is wrong, and the quantum view is correct.
But it just turns out that there's a limit in which the quantum world looks approximately classical.
>>>There are only a few things that I think are exactly correct in physics, and quantum mechanics is one of them, alongside Relativity.
...unless I have understood it otherwise, but quantum mechanics is still an approximation of things we simply are unable to measure individually - mostly because of speed and have to resort to guessing that approximation of that limited time period, which is still too long. It would be the same as trying to guess position of a ship during voyage across the ocean and taking the smallest measurable time period as 100 years, in which the ship has been already sunk out of existence, while smaller time period would have given us better picture and quantum mechanics that we are able to use has exactly that issue - we are unable to measure and record particles at smaller time intervals. At best we can see trajectories of particles long gone.
Also, this book is not agreeing with your statement, to me which sounds like Religion(because you have no explanation at all!) and should not be part of Science.