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Why is Maxwell's theory so hard to understand? (2007) [pdf]

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Re: Why is Maxwell's theory so hard to understand? (2007) [pdf]

#31

Post by DrDeWitt »

eru wrote: post #16
DrDeWitt wrote: post #7

Excellent essay. The thing I do not agree with is how they mention that one has to abandon natural language to understand quantum mechanics. The only reason why we made the jump from Newton to Einstein through Maxwell's theory is Einstein's intuition of the physics behind electrodynamics

> The only reason why we made the jump from Newton to Einstein through Maxwell's theory is Einstein's intuition of the physics behind electrodynamics I'm not sure that's true. What kind of model of causality are you using here? Other people were also on the cusp of doing (most of) what Einstein did. Ultimately, without Einstein most likely progress would have been delayed by a few years, and the laurels would be spre…

I would argue that Einstein made big leaps in knowledge to formulate SR and even more to formulate GR. He was able to imagine the motion of a body through a curved space-time as the source of gravity imo something that most people would not be able to do.

Re: Why is Maxwell's theory so hard to understand? (2007) [pdf]

#32

Post by notresidenter »

The two-layer separation of our world between imperceivable objects that define perceivable objects seems quite similar to how philosophy is essentially split between metaphysics and philosophy that takes things for granted from that "first layer".

> The reason for these arguments is that the various interpreters are trying to describe the quantum world in the words of everyday language, and the language is inappropriate for the purpose. Everyday language describes the world as human beings encounter it. Our experience of the world is entirely concerned with macroscopic objects which behave according to the rules of classical physics. All the concepts that appear in our language are classical. [...] The battles between the rival interpretations [of quantum dynamics] continue unabated and no end is in sight.

Replace 'quantum dynamics' with metaphysics (or post-Kantian metaphysics) and the statement seems true as well.

Re: Why is Maxwell's theory so hard to understand? (2007) [pdf]

#33

Post by DrDeWitt »

deepnet wrote: post #17
DrDeWitt wrote: post #7

Excellent essay. The thing I do not agree with is how they mention that one has to abandon natural language to understand quantum mechanics. The only reason why we made the jump from Newton to Einstein through Maxwell's theory is Einstein's intuition of the physics behind electrodynamics

Natural language can conjure the visual imagination of intuition, but it is less specific than images themselves. Einstein reportedly ran thought experiments in his imagination. His intuition was visual and dynamic. That is images that change - animations. A natural language description of relativity is one step removed from the moving images of Einstein's intuition. Fields are not grounded in everyday experience but…

You are probably right that natural language is not synonymous to a physical intuition. However, I believe that the way quantum theories are taught or even understood are in a much less intuitive manner than GR. Something that is evident by the number of different interpretations of quantum mechanics

Re: Why is Maxwell's theory so hard to understand? (2007) [pdf]

#34

Post by lchengify »

Only tangentially related, but I highly recommend watching Veritasium's YouTube video on electricity if you're curious as to how Maxwell's fields create the current / amp abstractions in EE [1].

It's a common misconception that electrons or current transfer energy. In reality it's the electric field that exists between the wires that is doing the heavy lifting, the electrons in the wires are just controlling the field.

This has always confused me and I was very irritated when I first learned electromagnetics about how rote all the initial learnings are. I wish more work was put earlier into making everything relate back to Maxwell's equations to make it make sense.

[1] https://www.youtube.com/watch?v=bHIhgxav9LY

Re: Why is Maxwell's theory so hard to understand? (2007) [pdf]

#35

Post by eru »

kragen wrote: post #21
eru wrote: post #18

Earlier quoted context omitted.

Keep in mind that we for all the talk of 'abandoning' the Newtonion paradigm, it's predictions are still valid for a large space of conditions. Eg NASA uses Newtonian mechanics to fly all their spacecraft. Special relativity includes classical mechanics when speeds are low. In the same way, any replacement for Maxwell's paradigm must reproduce the predictions of Maxwell's equations under the large swathe of condition…

yes, i thought that was too obvious to be worth saying, but i'm glad you've said it so the knuckle-dragging contingent don't think i'm endorsing their untutored 'theories' for that matter i use the aristotelian paradigm of physics when i expect my bed to stop moving when i stop pushing it across the floor; i don't bother with calculating the deceleration due to the friction coefficient with the floor

Sorry, I think the first part of your original comment was a bit confusing. Upon rereading: the second part already made it clear that this is what you meant.

Re: Why is Maxwell's theory so hard to understand? (2007) [pdf]

#36

Post by eru »

bigboy12 wrote: post #27
eru wrote: post #16

Earlier quoted context omitted.

> The only reason why we made the jump from Newton to Einstein through Maxwell's theory is Einstein's intuition of the physics behind electrodynamics I'm not sure that's true. What kind of model of causality are you using here? Other people were also on the cusp of doing (most of) what Einstein did. Ultimately, without Einstein most likely progress would have been delayed by a few years, and the laurels would be spre…

Everyone seems to think they would have figured out Einstein’s theory but they didn’t until Einstein did.

Huh? Where did I say I would have figured it out?

Albert Einstein was smart, and he definitely was smarter than me. But his achievements weren't beyond all the other smart people. Especially individually and with more time.

See also how Newton and Leibniz came up with calculus at the same time. Or how public key cryptography was invented independently multiple times.

Re: Why is Maxwell's theory so hard to understand? (2007) [pdf]

#37

Post by andyferris »

DrDeWitt wrote: post #12
GolDDranks wrote: post #10

Earlier quoted context omitted.

Particles and antiparticles. But I think he's trying to make a slightly more general point: why are "parities" (2-fold symmetries) so common in nature and mathematics? Why not more 3-fold symmetries?

As the other reply said, in QCD you have "3 things that combine to nothing." If I had to guess why they are not so common I would say that the more variables you add in a theory the more complicated you make it. So by Occam's razor we try to go for the simpler models/structures.

One line of thought here is that maybe there do exist larger, more complex symmetry groups that can broken to create more complex "charge" particles (e.g. electric charge (Obviously I can't say whether that is true or not, but it might be a possible explanation of current observations).

Re: Why is Maxwell's theory so hard to understand? (2007) [pdf]

#38

Post by andyferris »

im3w1l wrote: post #13
GolDDranks wrote: post #10

Earlier quoted context omitted.

Particles and antiparticles. But I think he's trying to make a slightly more general point: why are "parities" (2-fold symmetries) so common in nature and mathematics? Why not more 3-fold symmetries?

Maybe sound is an illustrative example. The air pressure is a positive scalar quantity. We are interested in the deviations from the mean. Deviations can be both positive and negative. A positive and a negative deviation cancel (in absolute terms: a larger than normal pressure and lesser than normal pressure will average to something more typical)

This is a good explanation for e.g. electric charge (which is scalar, just like presure), but color in QCD really is a bit more multidimensional in behavior where you can get things like red + green = -blue and so-on.

Re: Why is Maxwell's theory so hard to understand? (2007) [pdf]

#40

Post by eru »

DrDeWitt wrote: post #31
eru wrote: post #16

Earlier quoted context omitted.

> The only reason why we made the jump from Newton to Einstein through Maxwell's theory is Einstein's intuition of the physics behind electrodynamics I'm not sure that's true. What kind of model of causality are you using here? Other people were also on the cusp of doing (most of) what Einstein did. Ultimately, without Einstein most likely progress would have been delayed by a few years, and the laurels would be spre…

I would argue that Einstein made big leaps in knowledge to formulate SR and even more to formulate GR. He was able to imagine the motion of a body through a curved space-time as the source of gravity imo something that most people would not be able to do.

I agree that what Einstein did was beyond most people. But not beyond all of the great physicists of the time, especially if given more time.
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