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[personal profile] mmcirvin
Somehow I missed the minor fuss over this Bruno Maddox column about the mystery of magnetism. It'd be more interesting were the title and subhead actually true:
Three Words That Could Overthrow Physics: “What Is Magnetism?” — The standard model still doesn't describe magnets' spooky action at a distance.
I know that authors often don't have any control over titles and subheads, but the body of the article actually reveals that the standard model fails to explain magnetism to the personal satisfaction of Bruno Maddox without using scary mathematics and things he doesn't believe in.

He's a humor columnist and I'm not sure how serious he's being—I suspect not very. But I think there's a core of real frustration here, and instead of picking apart his objections, which other people have already done, I'm more interested in thinking about why he's so frustrated and what can be done about it.


After all, if you try to explain why X is true using a physical theory, it's obvious that you can turn this into an infinite regress: "yes, but why is the theory used to explain X itself true?" In the end it's not much different from a kid asking "Why?" repeatedly; a few iterations and you'll fall off the edge of human understanding. Surely nobody could reasonably expect that not to happen, for some explanation to appear that itself needs no explanation. I suppose people have tried to derive physics from pure logic, but such efforts have not gotten very far. The most fundamental physics we know still seems to be a bunch of logically contingent statements that we justify by saying "well, this seems to jibe with experiments", and if you're looking for ultimate explanations, that's upside down.

I think it's more that people intuitively expect more fundamental explanations to be more intuitively accessible by virtue of being simpler. But in physics you really end up going the other way. It turns out that the things we think of as intuitive—bricks smashing into walls, liquids pouring out of jars, physical variables that always have definite values, etc.—are the higher-order consequences of simple interactions that are really very weird. And there is something unsatisfying about this, but nobody ever said the world was obliged to satisfy us.*


He mentions virtual particles, and he's actually getting at a lie-to-children that occasionally bothers me in pop-physics expositions: they sometimes treat virtual particles as if they provided this classically intuitive picture of the action of fields as if they just consisted of little bullets shooting out of things and knocking other things around. They then immediately get into a heap of trouble trying to explain attractive forces, at which point the usual dodge is to say something like "welllll, these are just fictive devices for describing quantum fields anyway", which resolves precisely nothing and gives people like Bruno Maddox the idea that scientists are trying to pull a fast one. As I tried to get across in this old FAQ, you actually can explain attractive forces and other types of forces using virtual particles, but it involves taking their quantum nature very, very seriously, which really doesn't make the picture simpler or more intuitive unless you've already spent years filling your head with quantum mechanics.

So I'm not sure much can be done to satisfy people who want intuitive and compelling fundamental explanations, because they won't get them. But maybe we can do a little better by not oversimplifying to the point that people feel lied to.


*What complicates it even further for the specific case of magnetism is that ferromagnetic behavior in bulk materials really is a pretty complicated and hard-to-explain thing even given the fundamental physics in the Standard Model, and I'm not sure I personally understand it myself. But that's a side issue from "spooky action at a distance"; I rather suspect he's frustrated even by the description given for the magnetism of fundamental particles.

Even if you don't mind

Date: 2008-07-22 01:13 am (UTC)
From: [identity profile] notr.livejournal.com
the quantum nature of virtual particles and the sometimes backwards-looking forces, they still don't remove action at a distance from any explanations. Where do the virtual particles arise from? The field, created at a distance by the real particles.

Re: Even if you don't mind

Date: 2008-07-22 01:25 am (UTC)
From: [identity profile] mskala.livejournal.com
But is it spooky action at a distance?

Even spookier

Date: 2008-07-22 12:35 pm (UTC)
From: [identity profile] notr.livejournal.com
than direct action by the field on the real particles, since the virtual particles are just ghosts!

Date: 2008-07-22 06:28 am (UTC)
From: [identity profile] aderack.livejournal.com
It's maybe an easier pill when you establish that science is merely a series of careful, reasoned observations about how things seem to work. The concept of an objective truth that explains what, how, and why things are is kind of beyond the scope of what is knowable. All we can know is what we see.

Date: 2008-07-22 06:31 am (UTC)
From: [identity profile] aderack.livejournal.com
I mean. In a sense, there's something reassuringly practical about science. We can't know the absolute truth about anything, but hey. This model seems to describe things pretty well.

Date: 2008-07-22 06:47 am (UTC)
From: [identity profile] aderack.livejournal.com
That is to say, a lot of the frustration seems to come from an expectation that science is a source of fundamental answers about the universe -- essentially a sort of belief system. Which it's not; it's simply descriptive. This seems to kind of freak some people out, like realizing Dad doesn't know everything after all.

There's a reason why science used to be called natural philosophy; it's just one of many ways of describing the world -- namely, an attempt to reverse engineer its apparent physical rules, to give us a leg up in the game of life.

The question as to why we're playing the game to begin with, or why the rules have been set out the way they have been, remains a personal matter. Personally I think it's beside the point, since it's not like there's anything we can do about it.

Date: 2008-07-22 01:44 pm (UTC)
From: [identity profile] mskala.livejournal.com
I think the same mistake can be made in the other direction too - a lot of friction between science and belief seems to come from users of science demanding that belief be a (necessarily inferior) form of science, address the same questions science addresses, and use the same forms of proof and argumentation.

Date: 2008-07-22 02:35 pm (UTC)
From: [identity profile] dr-strych9.livejournal.com
More accurately, the friction comes from users of science demanding, quite reasonably, that believers stop trying to address the same questions science addresses using the irrational methods of antiscience. So, to get back to the point of the original post: more friction, please.

Date: 2008-07-22 02:39 pm (UTC)
From: [identity profile] mskala.livejournal.com
more friction, please.

And that's why it doesn't end.

Date: 2008-07-22 03:54 pm (UTC)
From: [identity profile] thesaucernews.livejournal.com
think it's more that people intuitively expect more fundamental explanations to be more intuitively accessible by virtue of being simpler. But in physics you really end up going the other way. It turns out that the things we think of as intuitive—bricks smashing into walls, liquids pouring out of jars, physical variables that always have definite values, etc.—are the higher-order consequences of simple interactions that are really very weird.

'We live on an island of placid ignorance in the midst of black seas of infinity, and it was not meant that we should voyage far.'

I think an anthropic principle is at work in many people, that not only must the universe reduce to fundamental truths which make sense, those truths must make sense to me, otherwise it opens up the unsettling possibility that, in actual fact, the world is not obliged to satisfy us.

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