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Is the Schrödinger Equation True?

scientificamerican.com

21–30 of 171 posts

Re: Is the Schrödinger Equation True?

#21
post #17
post #15

Earlier quoted context omitted.

That's sounds like philosophy, I'm out!

And just one post back you recommended a Philosophical essay ;)

It was partly a tongue-in-cheek dogwhistle to the physics crowd, but I do sort of feel that even the essay I cite is useless - interesting, yes. I (and I have tried) really struggle to see what the point is in learning all these philosophy terms when it usually or always ends up being unfalsifiable or a overly proud euphemism for yet another concept.

To take a specific example, I'm curious what post-structuralism actually means as applied to the structure I was trying to refer to - there are certain symmetry groups that seem to apply everywhere we look, but the actual structure is itself isn't a symbolic concept in the same way the standard model is.

Re: Is the Schrödinger Equation True?

#22
post #6

One of the interesting questions (without any satisfactory answers) in Philosophy is “How does language relate to the world?” Perhaps it doesn’t. Perhaps language is just a tool we, humans, use for thinking and representing our knowledge. Mathematics is a language... Mathematical objects need not exist anywhere else but in the Mathematician’s head.

Mathematics is uniquely weird in that anywhere in the universe, a species can come up with the same things... So to say Mathematics is not real, and yet it is independently discoverable by anyone is just really weird to me.

There are very credible linguists who theorize that there’s a universal human grammar and language foundation. It’s not a stretch to think that if they’re right about humans, the theory may apply to other life with language which we haven’t encountered yet.

If that’s the case, the property you’re describing belongs to abstract thought and language generally, of which mathematics is a subset.

Re: Is the Schrödinger Equation True?

#23
post #4

The author of this piece says he was struggling to understand complex conjugates. If you don't understand what that is, please read the wikipedia, so you can contextualize his level of familiarity with the material he speaks about. I don't think the author is being dishonest. But that admission is extremely striking to me. [edit: Can some admin give me guidance on how to make the point I'm clearly trying to make? I'm…

>complex conjugates

I wonder if there would be less objection by the author if he was exposed to geometric algebra, to help with difficulties encountered by sqrt(-1) philosophical issues.

Re: Is the Schrödinger Equation True?

#24
Compared to physicists, engineers are humble.

Well. Anecdotally, when there's open house at the physics department, the guys that will tell you how quantum mechanics and/or relativity are wrong tend to have a background in engineering.

Also note that not everyone subscribes to what the article calls the 'Gospel of Physics': Quite a few of us are well-aware that the map is not the territory...

Re: Is the Schrödinger Equation True?

#25
post #2

The article touches upon something that I think most people that learn about physics don't realize. The models physicists use to describe nature do NOT exist in reality. They are mere concepts that work well to describe natural phenomena. My favourite example for this is the electron. Does an electron how we describe it in quantum mechanics exist in nature? The answer is no. The electron is a model construct we have…

Physics isn't special in this regard, though. All conscious thought is about models, abstractions and filing things away in boxes. I might think this post of mine starts with the letter P, but if I made the http request by hand, starting it by sending the utf8 encoding of P to the network card won't work, because I need headers. On the other hand if my child tried to render the opening P I'd ask her to not draw on my…

Physics is slightly special in that it tries to optimise for mathematical simplicity rather than ease-of-conscious-thought. If we find a simpler or more predictive model for the electron, physicists will happily abandon the model we currently have, while nothing will destroy our brain's model of 'what I type is what is sent'. Conscious thought isn't even required for the process of physics, we only use it because it is the only thing we have to approximate the mathematical reasoning that physics does require.

Re: Is the Schrödinger Equation True?

#26
post #19

Earlier quoted context omitted.

Mathematics is uniquely weird in that anywhere in the universe, a species can come up with the same things... So to say Mathematics is not real, and yet it is independently discoverable by anyone is just really weird to me.

The line of reasoning is purely speculative. Since we are the only species who have Mathematics, I will continue insisting Maths is invented, till we can compare notes with other life forms.

We’re the only species with which our species communicates maths. But we observe other species expressing mathematical properties we communicate. Does (for example) a snail “know” or “understand” the “golden ratio”? Who knows! But a snail’s shell expresses it. That’s partly something we can observe (so it can be designated “invented”), but partly something that appears so much it’s either a biological commonality, subject to some unknown universal constant, or an expression that many forms of life find a way to express.

Re: Is the Schrödinger Equation True?

#27
post #11
post #4

The author of this piece says he was struggling to understand complex conjugates. If you don't understand what that is, please read the wikipedia, so you can contextualize his level of familiarity with the material he speaks about. I don't think the author is being dishonest. But that admission is extremely striking to me. [edit: Can some admin give me guidance on how to make the point I'm clearly trying to make? I'm…

I mean.. if their problem is not understanding the math of conjugation at all, then yes, they're pretty elementary and are going to have trouble with QM. But if their problem is not being able to stomach the "just-because" explanations that every QM resigns to using to explain wtf complex conjugation has to do with reality, then I completely, totally sympathize. Learning QM consists of learning to silence your object…

I'd maybe swallow this explanation for complex conjugates as applied to QM. (They're still extremely useful for e.g. circuit analysis, as a practical application)

But it's not just complex conjugates, but eigenvectors as well. Also spectacular: "the square root of a negative number, which by definition does not exist"

Uh. That's a complete lack of connection to anything beyond 10th grade math. Maybe not the ideal foundation for criticizing QM.

And yes, I get the complaint that QM comes with a lot of "if you just hold your nose and accept this", and intuition doesn't really work for it - but that's hardly a valid criticism by itself, outside of saying "well, this is hard to understand".

And the idea that a mathematical model isn't perfect and as a result of that can't be true really just betrays a complete misunderstanding how models work.

This piece boils down to "I don't understand it, and so it can't be correct".

Re: Is the Schrödinger Equation True?

#28

Earlier quoted context omitted.

Mathematics is uniquely weird in that anywhere in the universe, a species can come up with the same things... So to say Mathematics is not real, and yet it is independently discoverable by anyone is just really weird to me.

There are very credible linguists who theorize that there’s a universal human grammar and language foundation. It’s not a stretch to think that if they’re right about humans, the theory may apply to other life with language which we haven’t encountered yet. If that’s the case, the property you’re describing belongs to abstract thought and language generally, of which mathematics is a subset.

The idea of universal grammar is that it is the portion of human language that is hardcoded into the genetics of humans. We would not expect other species to have the same universal grammar that humans do.

Re: Is the Schrödinger Equation True?

#29
Reminds me of course of the great anecdote attributed to quantum physicist Wolfgang Pauli:

"a friend showed Pauli the paper of a young physicist which he suspected was not of great value but on which he wanted Pauli's views. Pauli remarked sadly, 'It is not even wrong'."

Re: Is the Schrödinger Equation True?

#30
Not sure I agree with him. What does something being real mean? It's got to mean that observations are consistent with the description of that something. That's actually all we can do, check that observations aren't disagreeing with what the model said. So if an electron is a tiny little thing that is deflected by a magnetic field, has a certain mass, etc, then it's real insofar as we observe those qualities. In the same way if Santa Claus isn't real, it's because there's issues with the evidence.

This doesn't preclude there being a better model of course. Observations can get more sophisticated, revealing that your model needed adjustment. Or parsimony can drive and someone finds a way to describe multiple phenomena at once, eg electromagnetism.

As for why mathematics is great at describing nature, it's because there's loads of it, since it's an extensible system of logic. Someone somewhere is going to find a way of describing how asteroids go round, and being a kind of logic there's no way you would say it wasn't math, regardless of what exactly it was. Epicycles are math too, despite not being the exact right way to think about it.

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