What do you mean “mechanical/local”? Maxwell’s equation’s (in what I consider their most fundamental form) describe how the electric and magnetic fields change at any point based on derivatives of those fields, the charge, and the movement of charges at that point. That is certainly local. And, together with the laws describing the forces experienced by charges in the fields (also local), they mechanically describe how a system will evolve.
OK, I’ll update again that it is just me that doesn’t understand the light wave mechanically. (I didn’t mean this facetiously—I know light is really strange for everyone, I just meant that I can’t seem to possibly understand it.)
Do you mean that you do not understand Maxwell’s equations? That you don’t understand how the wave mechanics are derived from Maxwell’s equations? Or that some part of this is not “mechanical”?
I’m beginning to suspect that my insistence on understanding things a certain way is peculiar and possibly overly narrow.
But suppose that I look outside my window and see a light wobbling across the horizon. I think that I don’t understand the trajectory of the light. Then someone finds the equation that describes the motion of the light: it turns out to be perfectly regular and periodic. I still feel I don’t understand it. For me, the path of the light isn’t understood until you discover that the light is a reflector attached to the wheel of a car, and the trajectory you see is a combination of the car’s linear movement and wheel’s rotation. This is what I mean by a mechanical understanding.
I could study Maxwell’s equations, but I know they wouldn’t help. Do we have a ‘mechanical’ understanding of the motion of light, or just the equation description?
Are you saying you want to understand light as being made out of components that behave like the macroscopic objects you are used to interacting with? That isn’t going to happen, because light does not work that way.
I don’t mind if light behaves in different ways than I’m used to, but I still expect that these ways are causally dependent upon other things. Especially with a spatial pattern, I expect that any pattern produced by certain geometric rules can be reproduced by a model of those rules.
Even at the macroscopic scale—if a model is possible (physically realizable) at that scale. If it is not possible, I would have to spend a lot of mental energy modeling those rules mentally, but that would still lead to mechanical understanding. My problem is that I haven’t heard (or don’t believe I’ve heard) exactly what rules should be modeled.
Um. I’m having one of those I-can’t-believe-I’ve-been-this-stupid-over-the-last-ten-years moments.
I went back and reread what you wrote and the part I missed before was this:
The wave described is light.
So it isn’t that light “happens to follow” this wave equation. That wave equation IS light—that is, that specific interaction between the electric and magnetic fields is light.
Honestly, I’d never thought of it that way before. I can go back to that chapter in electromagnetism and see if I understand things differently now.
I look at the light bulb on my desk and I wouldn’t even call it ‘light’ anymore. It is electromagnetic interaction.
I photographically recall the poster over an exhibit at a science museum, “Light Is Electromagnetic Radiation’. I thought that meant that light was radiation (obviously, it radiates) that was associated in some way with electromagnetic theory and I remember thinking it was a decidedly unpleasant verbal construction.
You know, this really calls for a cartoon-y cliche “light bulb turning on” appearing over byrnema’s head.
It’s interesting the little connections that are so hard to make but seem simple in retrospect. I give it a day or so before you start having trouble remembering what it was like to not see that idea, and a week or so until it seems like the most obvious, natural concept in the world (which you’ll be unable to explain clearly to anyone who doesn’t get it, of course).
(which you’ll be unable to explain clearly to anyone who doesn’t get it, of course)
Seriously. Apparently, I wrote the key insight she needed (not knowing that it was the missing insight), but she didn’t click on it the first time, and then, as I am asking questions to try to narrow down what the confusion is, something I said, as a side effect, prompted her to read that insight again and she got it. Now, how can one systematically replicate a win like that?
I remember you and I also discussed what it means to understand something, and I definitely sympathize and largely agree with your standard for what counts as “understanding”. (I’ll find the link to that discussion when I get a chance.)
My standard is that you understand something if and to the extent that:
1) You have a mathematical model that generates the observations with good success. (Not necessary here what labels you use—this part can be “Chinese room”-ish.)
2) That model is deeply connected (via the entities it shares, quantities it uses, mutual interaction, etc.) to your model for everything else, and thus connected, ultimately, to your intuitive (raw, qualia-laden) model of the world.
Correct me if I’m wrong, but I think this is where you are: for light, you understand it in the sense of meeting 1), but don’t meet it with respect to 2). Would you say that is accurate?
What do you mean “mechanical/local”? Maxwell’s equation’s (in what I consider their most fundamental form) describe how the electric and magnetic fields change at any point based on derivatives of those fields, the charge, and the movement of charges at that point. That is certainly local. And, together with the laws describing the forces experienced by charges in the fields (also local), they mechanically describe how a system will evolve.
OK, I’ll update again that it is just me that doesn’t understand the light wave mechanically. (I didn’t mean this facetiously—I know light is really strange for everyone, I just meant that I can’t seem to possibly understand it.)
Do you mean that you do not understand Maxwell’s equations? That you don’t understand how the wave mechanics are derived from Maxwell’s equations? Or that some part of this is not “mechanical”?
I’m beginning to suspect that my insistence on understanding things a certain way is peculiar and possibly overly narrow.
But suppose that I look outside my window and see a light wobbling across the horizon. I think that I don’t understand the trajectory of the light. Then someone finds the equation that describes the motion of the light: it turns out to be perfectly regular and periodic. I still feel I don’t understand it. For me, the path of the light isn’t understood until you discover that the light is a reflector attached to the wheel of a car, and the trajectory you see is a combination of the car’s linear movement and wheel’s rotation. This is what I mean by a mechanical understanding.
I could study Maxwell’s equations, but I know they wouldn’t help. Do we have a ‘mechanical’ understanding of the motion of light, or just the equation description?
Are you saying you want to understand light as being made out of components that behave like the macroscopic objects you are used to interacting with? That isn’t going to happen, because light does not work that way.
I don’t mind if light behaves in different ways than I’m used to, but I still expect that these ways are causally dependent upon other things. Especially with a spatial pattern, I expect that any pattern produced by certain geometric rules can be reproduced by a model of those rules.
Even at the macroscopic scale—if a model is possible (physically realizable) at that scale. If it is not possible, I would have to spend a lot of mental energy modeling those rules mentally, but that would still lead to mechanical understanding. My problem is that I haven’t heard (or don’t believe I’ve heard) exactly what rules should be modeled.
Earlier I said (emphasis added):
Would it make more sense if I said:
Um. I’m having one of those I-can’t-believe-I’ve-been-this-stupid-over-the-last-ten-years moments.
I went back and reread what you wrote and the part I missed before was this:
So it isn’t that light “happens to follow” this wave equation. That wave equation IS light—that is, that specific interaction between the electric and magnetic fields is light.
Honestly, I’d never thought of it that way before. I can go back to that chapter in electromagnetism and see if I understand things differently now.
I look at the light bulb on my desk and I wouldn’t even call it ‘light’ anymore. It is electromagnetic interaction.
I photographically recall the poster over an exhibit at a science museum, “Light Is Electromagnetic Radiation’. I thought that meant that light was radiation (obviously, it radiates) that was associated in some way with electromagnetic theory and I remember thinking it was a decidedly unpleasant verbal construction.
I’m thankful, and sorry...
You know, this really calls for a cartoon-y cliche “light bulb turning on” appearing over byrnema’s head.
It’s interesting the little connections that are so hard to make but seem simple in retrospect. I give it a day or so before you start having trouble remembering what it was like to not see that idea, and a week or so until it seems like the most obvious, natural concept in the world (which you’ll be unable to explain clearly to anyone who doesn’t get it, of course).
Seriously. Apparently, I wrote the key insight she needed (not knowing that it was the missing insight), but she didn’t click on it the first time, and then, as I am asking questions to try to narrow down what the confusion is, something I said, as a side effect, prompted her to read that insight again and she got it. Now, how can one systematically replicate a win like that?
Be polite and patient when people are confused?
Well, that is important. But that is more part of not automatically failing, than actually making progress towards dispelling the confusion.
Lacking understanding, that’s the best advice I can give.
I remember you and I also discussed what it means to understand something, and I definitely sympathize and largely agree with your standard for what counts as “understanding”. (I’ll find the link to that discussion when I get a chance.)
My standard is that you understand something if and to the extent that:
1) You have a mathematical model that generates the observations with good success. (Not necessary here what labels you use—this part can be “Chinese room”-ish.)
2) That model is deeply connected (via the entities it shares, quantities it uses, mutual interaction, etc.) to your model for everything else, and thus connected, ultimately, to your intuitive (raw, qualia-laden) model of the world.
Correct me if I’m wrong, but I think this is where you are: for light, you understand it in the sense of meeting 1), but don’t meet it with respect to 2). Would you say that is accurate?