Bad Maxwell
September 6, 2009 8:21 AM   Subscribe

▼●B≠0
posted by Confess, Fletch (91 comments total) 18 users marked this as a favorite

 
Sorry, but ▼●B=0.

These are not true magnetic monopoles.
posted by vacapinta at 8:33 AM on September 6, 2009 [4 favorites]


Useless without hyped up speculation on how we can use this.

Oh and magnetic gas, someone want to broach that subject?
posted by furtive at 8:33 AM on September 6, 2009


I saw that equation and I had a weird sense of panic, "Oh crap oh crap oh crap," because magnetic monopoles on the order of "at least one per universe" (what am I supposed to do with a number like that?) are a prominent feature of many theories of predictive, if not explicative, power. Suddenly, thoughts of the kinds of technologies one might be able to conjure up from this appeared — nearly as revolutionary as electricity might be. I thought about the vindication of theories far less sexy than M-theory.

This, though, makes me feel cheated. It is the equivalent of a "sonic black hole" for magnetism, it might as well be an itty-bitty Halbach array. It's the Emergent Emperor's New Clothes, woven from Dirac strings.

You just gave me physics blueballs.
posted by adipocere at 8:38 AM on September 6, 2009 [44 favorites]


This is like the physics nerd equivalent of Goodnight Sweet Prince posts on 4chan.
posted by phrontist at 8:52 AM on September 6, 2009 [1 favorite]


Since I'm a biology person, can someone care to explain precisely what the problem is here?
posted by kldickson at 8:57 AM on September 6, 2009 [1 favorite]


Unicode nitpick: it's ∇, not ▼.
posted by Johnny Assay at 8:59 AM on September 6, 2009 [6 favorites]


This is all well and good, but how does it help me turn lead into gold?
posted by infinitywaltz at 9:16 AM on September 6, 2009 [1 favorite]


To phrase infinitywaltz' query in another way, what are the practical applications of real monopoles? Many folks are saying that it would change things, how so?
posted by bigmusic at 9:28 AM on September 6, 2009


"For the development of new technologies this can have big implications. Above all it signifies the first time fractionalisation in three dimensions is observed."


Exactly.
posted by stbalbach at 9:38 AM on September 6, 2009


I maintain nonetheless that yin-yang dualism can be overcome. With sufficient enlightenment we can give substance to any distinction: mind without body, north without south, pleasure without pain. Remember, enlightenment is a function of willpower, not of physical strength.

Chairman Sheng-ji Yang
"Essays on Mind and Matter"
posted by The Whelk at 9:40 AM on September 6, 2009 [7 favorites]


Since I'm a biology person, can someone care to explain precisely what the problem is here?

There's no such thing as biology. There's no such thing as chemistry.

There is only physics.

Mathematicians back the fuck up.
posted by loquacious at 10:00 AM on September 6, 2009 [25 favorites]


Who is the intended audience for this piece? Other physicists? No -- those who are in the field will want to see the details of what was actually done, and will wait for the publication, (or they already know). Other scientists? No -- because they don't explain what they mean by statements like "the neutrons scatter as a reciprocal representation of the Strings." Or how "the strings are visible and have magnetic monopoles at their ends" is any different from the claim "I can see this bar magnet and there is a north pole at one end!" The general public? I hope not. Because if so, shouldn't they actually explain stuff?
posted by Killick at 10:06 AM on September 6, 2009 [1 favorite]


I too felt very physics blueballed (perfect description) until the final sentence. "Above all it signifies the first time fractionalisation in three dimensions is observed." Now I don't know what I'm feeling, that certainly sounds exciting.

Physics blueballs, or physics shejustgotoutwhipsandshacklesohgodwhatishappeningnow?
posted by Shutter at 10:08 AM on September 6, 2009 [1 favorite]


Until I can by one at that online atomic supply store, they don't exist.
posted by GuyZero at 10:10 AM on September 6, 2009


Until I can by one at that online atomic supply store, they don't exist.

Have you tried a boutique Hi-Fi shop? They probably have some on offer as a very expensive spray or paint for treating interconnect cables.
posted by loquacious at 10:18 AM on September 6, 2009 [7 favorites]


vacapinta : Sorry, but ▼●B=0. These are not true magnetic monopoles.

They probably do actually exist, even if the linked article doesn't have the real deal... Perhaps not the more convenient Dirac version, but in some form. As for whether humanity can/will ever find one and have the ability to do anything useful with it... That remains an open question.


Shutter : "Above all it signifies the first time fractionalisation in three dimensions is observed." Now I don't know what I'm feeling, that certainly sounds exciting.

Mostly, that just means the flux between the two "mono"poles here remains confined to a non-zero-width-but-basically-1D region. You could arguably say the same thing about the "flux" of water through a garden hose, though not quite at the same fundamentally cool level. :)
posted by pla at 10:21 AM on September 6, 2009


There is only physics.

There are only physical particles, but there is not only physics.

Photosynthesis is a biological, not a chemical or physical, process.
posted by kenko at 10:21 AM on September 6, 2009 [2 favorites]


vacapinta, adipocere, any chance you two can explain to the masses why this isn't an important step forward? Honest question, no snark. I was under the impression that observable monopoles were an important step froward.
posted by lekvar at 10:22 AM on September 6, 2009


Next logical step: no such thing as photosynthesis. Well, if you like.
posted by kenko at 10:23 AM on September 6, 2009


loquacious : Have you tried a boutique Hi-Fi shop? They probably have some on offer as a very expensive spray or paint for treating interconnect cables.

I've heard Monster's low-monopole cables can reduce bit-slew in optical runs by up to 99%! Well worth the $499/ft they cost, for the "real" audiophiles.
posted by pla at 10:24 AM on September 6, 2009 [2 favorites]


Next logical step: no such thing as photosynthesis. Well, if you like.

You simply have the wrong end of the tree. If you can describe how photosynthesis actually works without resorting to physics - be my guest.

But I'm pretty sure photons and atoms are involved at some point.

I am not a physicist. I'm just an idiot without a degree, so what do I know?
posted by loquacious at 10:31 AM on September 6, 2009 [1 favorite]


on the order of one per universe

And they found it?! Now that's impressive. I wouldn't have had the patience to keep looking.
posted by msalt at 10:33 AM on September 6, 2009 [8 favorites]


With a little luck this will be bigger than cold fusion.
posted by digsrus at 10:35 AM on September 6, 2009 [1 favorite]


All science is either physics or stamp collecting.
posted by jenkinsEar at 10:38 AM on September 6, 2009 [6 favorites]


Who is the intended audience for this piece?

It's science pr0n : It is really aimed at people who aren't doing it for whatever reason, but enjoy seeing it done -- even if the excitement is obviously faked.
posted by Dr Dracator at 10:42 AM on September 6, 2009 [9 favorites]


With a little luck this will be bigger than cold fusion.

Why would you need luck? So far the invention of the George Foreman grill, OxyClean and the Shamwow have all been bigger than cold fusion.
posted by loquacious at 10:42 AM on September 6, 2009 [4 favorites]


But I'm pretty sure photons and atoms are involved at some point.

I didn't deny that; after all, I did say that there are only physical particles.
posted by kenko at 10:43 AM on September 6, 2009


Photosynthesis is a biological, not a chemical or physical, process.
posted by kenko at 1:21 PM


Actually, at its core it is a physical process. Photon hits magnesium and gets it all excited. That starts a chain of events that, while physical in nature, only really make sense through a chemical and then biological lens. Saying that here is no chemistry or biology is reductio ad absurdam. But, since it's loquacious saying it, I wouldn't get all uppity about it. He's just kidding.
posted by kuujjuarapik at 10:49 AM on September 6, 2009


lekvar, this is not the discovery of a new fundemntal particle like the quark, , or electron - the discovery of which could greatly amend or extend our understanding of particle physics. This is like the discovery of the hole in semiconductors or the cooper pair in superconductors, a virtual or effective particle which is really the effect of interactions between lots of real particles.

It is a failure of science reporting that the articles reporting on the discovery aren't explaining this.
posted by sebastienbailard at 10:51 AM on September 6, 2009 [1 favorite]


I didn't deny that; after all, I did say that there are only physical particles.

Some of those particles are offended that you aren't describing them as waves, but it kind of depends on who is asking - and when.

Gleeful scientist-baiting aside - physics is a lot more than particles, so "there are only physical particles" isn't a statement I can let slide. You're either being too general and non-descript or you have a weird definition of physics.

Biology, chemistry and all of the other materials sciences except for pure mathematics* descend from physics.

*I said back the fuck up. I see you over there with your TNT, trying to prove P=NP.
posted by loquacious at 11:00 AM on September 6, 2009 [1 favorite]


Science has a much better summary, and the real article.
For decades, scientists have searched for magnetic monopoles--particles that, unlike traditional magnets, have just a north or south pole. This week in Science, two teams of condensed matter physicists independently report observations of the next best thing: tiny ripples in solid materials that act like the elusive particles. The find does not end the quest for bona fide monopoles, but it may herald the discovery of other weird "quasiparticles" in solids, as well as provide the basis for new technologies.
posted by a robot made out of meat at 11:10 AM on September 6, 2009 [13 favorites]


uh, yeah, i'm with vacapinta. if this is a "monopole" then electron holes are "positrons". booooo!
posted by sergeant sandwich at 11:21 AM on September 6, 2009 [1 favorite]


In my hunt for the secret of life, I started my research in histology. Unsatisfied by the information that cellular morphology could give me about life, I turned to physiology. Finding physiology too complex I took up pharmacology. Still finding the situation too complicated, I turned to bacteriology. But bacteria were even too complex, so, I descended to the molecular level, studying chemistry and physical chemistry. After twenty years work, I was led to conclude that to understand life we have to descend to the electronic level, and to the world of wave mechanics. But electrons are just electrons, and have no life at all. Evidently on the way I lost life; it had run out between my fingers.
-- Albert Szent-Gyorgyi (1972, The living state)
posted by benzenedream at 11:23 AM on September 6, 2009 [39 favorites]


Touché, benzenedream.
posted by loquacious at 11:57 AM on September 6, 2009


To phrase infinitywaltz' query in another way, what are the practical applications of real monopoles?

FASTER COMPUTERS!!!111

Also, a 74% reduction in ring around the collar.
posted by DU at 12:04 PM on September 6, 2009


Ok, I played fast and loose with my physics terminology.

But in what sense does chemistry descend from physics? Not etiologically, certainly; if you mean that behind any chemical process there are physical processes, then, sure, who'd deny that? Not I.

But it's also deceptive to say that photosynthesis is "a physical process"; kuujuarapik's formulation that it is "a chain of events that, while physical in nature, only really make sense through a chemical and then biological lens" is much apter. It is only in a biological light that photosynthesis can be interrupted, if say the plant in which it is occurring is annihilated. In the cycle illustrated here, there isn't a physical answer to the question "what happens after the NADPH becomes NADP-?", other than, whatever happens next, in the particular case, is what happens next: if what happens next is that the plant is incinerated, that's what happened next. But there is a biological answer: something happens with the malate, or whatever.

Blithe physical reductionists, subscribing not just to the thesis that everything that happens, happens physically, but also to the thesis that everything is ultimately explicable by the branch of science, physics, not only underestimate the difficulty of reducing (in that fashion) even chemistry to physics, they forget that several scientifically respectable things we might like to know about don't even exist in physics.

(Photosynthesis example taken from Michael Thompson, in I believe "The Representation of Life", which you can download, if you like, and read.)
posted by kenko at 12:05 PM on September 6, 2009 [1 favorite]


Damn, totally pwned.
posted by kenko at 12:06 PM on September 6, 2009


▼●B≠Ghostbusters 2?
posted by cazoo at 12:07 PM on September 6, 2009 [2 favorites]


Since I'm a biology person, can someone care to explain precisely what the problem is here?

Ok, I'm neither a physicist nor a mathematician, but I think I have the outlines okay.

In nature, we always observe magnetic fields in pairs. For every north pole, there's a south pole, and vice versa. Their strengths are always exactly equal... thus the equation in the link.

A monpole is a theoretical particle that is ONLY a north or south pole, without its pair. Such a thing has never been observed, and as far as I understand, only mathematics indicates that they might exist. No real observation has even hinted at it, as far as I know. An actual observation of a monopole would be a really, really big deal.

The reason people are getting physics blue balls is because this experiment didn't generate monopoles. It generated the usual dipoles, and split them apart over a distance. So each end kind of looks like a monopole, but it isn't. It's just sleight of hand.
posted by Malor at 12:12 PM on September 6, 2009 [1 favorite]


Nice quote, benzenedream. He was a giant. I understand his frustration in understanding something in certain terms--the paradigms of physiology, pharmacology, or microbiology--but not being able to go further and understand it fundamentally. But that's science,non? The art of the soluble.
posted by Turtles all the way down at 12:13 PM on September 6, 2009 [1 favorite]


So, how is this going to effect the next season of LOST?
posted by defenestration at 12:16 PM on September 6, 2009


Photon hits magnesium and gets it all excited.

So photons are abusers and magnesium is a masochist. Got it.
posted by WolfDaddy at 12:17 PM on September 6, 2009 [5 favorites]


kenko: As indicated above, I kid. Nicely worded rebuttal and commentary, though.
posted by loquacious at 12:18 PM on September 6, 2009


I believe this is presented as a big deal because even if they have not produced actual magnetic monopole "particles", it still demonstrates their existence. That is, either the divergence of B is always zero, or some monopoles must exist. That that have managed to constrain an area of space to have a non-zero div-B is therefore significant.

It is a bit like being able to say "we have managed to show electron holes therefore there must be such a thing as a positron".

A couple papers on that very topic have been featured on ars technica recently if you are interested. I don't have the links handy due to minor technical issues on my end.
posted by Fruny at 1:07 PM on September 6, 2009


Malor> A monpole is a theoretical particle that is ONLY a north or south pole, without its pair. Such a thing has never been observed, and as far as I understand, only mathematics indicates that they might exist. No real observation has even hinted at it, as far as I know. An actual observation of a monopole would be a really, really big deal.

A couple of comments. One, the existence of magnetic monopoles would explain why electric charge is quantized.

As far as real observations go, there was one highly disputed one some time ago by Blas Cabrera at Stanford University. The thing is, his argument was that his detector picked up a signal which could not be duplicated by any sort of glitch he could try to create (hitting the apparatus with a hammer, etc.).

The problems are that: 1) this isn't a highly convincing proof that you've found a monopole (and I'm not sure how seriously he thought others should take his result) and 2) nobody thinks free magnetic monopoles are so common that it would be anything other than extremely unlikely that one would have managed to pass through his detector, so the default assumption when anyone sees a signal is that he or she has fucked up somehow.

Frankly, there's no point in trying to have a dedicated magnetic monopole detector running, because any claimed experimental detection would be hugely disputed by the physics community.
posted by UrineSoakedRube at 1:19 PM on September 6, 2009 [1 favorite]


But I'm pretty sure photons and atoms are involved at some point.

Without biological entities of certain intelligence, there would be nothing out there to label these ideas with the names "photons" and "atoms", and thus physics would evaporate into æther.

Which suggests there is no such thing as physics, only philosophy.
posted by Blazecock Pileon at 1:35 PM on September 6, 2009 [2 favorites]


Without biological entities of certain intelligence, there would be nothing out there to label these ideas with the names "photons" and "atoms", and thus physics would evaporate into æther.

The absence of labels isn't the absence of the labeled.
posted by kenko at 1:42 PM on September 6, 2009 [4 favorites]


If you two are gonna start talking like that you're gonna have to learn to share.
posted by The Whelk at 1:45 PM on September 6, 2009 [1 favorite]


Photosynthesis is a biological, not a chemical or physical, process.

You're making baby Friedrich Wöhler cry!

In all seriousness, I'm a chemist in a bioassay group. We develop a mess of ELISA assays and weird behavior (odd spike recovery issues, non-linearity, cross reactivity) is just par for the course. A while back I did some work where I modeled a complex system and showed beyond any reasonable doubt that when we reached equilibrium we still had a mess of unbound ligands.

I was told I was too theoretical and they went back to talking about how we'd clearly used up all the antibody! Hello, on rates? Off rates? I'M THE ONE WHO HAD THREE HOURS OF BIOLOGY TO GO WITH HIS 157000 hours of chemistry. I should be the one whose mental model of antibodies is like Legos.
posted by Kid Charlemagne at 1:49 PM on September 6, 2009 [3 favorites]


The absence of labels isn't the absence of the labeled.

I was being a little silly, but it seems difficult to actually prove this statement, without someone around to do the labeling.
posted by Blazecock Pileon at 1:50 PM on September 6, 2009 [1 favorite]


Sure, but it seems difficult to actually believe its contrary, unless you think that intelligent life was around for all time.
posted by kenko at 1:52 PM on September 6, 2009 [1 favorite]


Which suggests there is no such thing as physics, only philosophy.

Christ, what a philosopher. Or more likely a metaphysician.

No. There's a forest, and a tree - and it makes a sound when it falls over. Even if it's a petrified forest.

There's also a bear and a pope and they're arguing about leaving the lid up or down.

Have you ever really looked at your hands, man?

posted by loquacious at 1:53 PM on September 6, 2009 [1 favorite]


In my admittedly singular view on this meta-meta derail, the metaphysicians and philosophers hang out (or are quarantined) with the math weirdos who are resolving Pi and wrestling with P=NP. This isn't really a bad thing. They throw great parties and they usually have the best drugs.

The part that I find alarming is that if they really do believe some of the more deeply esoteric things they believe about the fundamental nature of perception, awareness and the universe at large - why aren't they more concerned with accidentally pulling a divide-by-zero on reality or trying to resolve Pi to too many digits?

3.1415926535 ... 0342899999 ... 9999999999 *POP*

*vanishes in a puff of logic*
posted by loquacious at 2:06 PM on September 6, 2009


Sure, but it seems difficult to actually believe its contrary, unless you think that intelligent life was around for all time.

I don't know what this means, but labels like "photons", "electrons" and so forth are essentially mathematical ideas.

We then do science experiments to verify that these ideas reflect reality, and we can use the labels to do stuff, like make electricity.

In other words, a system of labeling reality ("science") only works to the extent that the verification step can take place and is repeatable.

Without human beings, or whatever, around to verifiably categorize things as "photons", "electrons" etc. with a language in place to do so, and a process in place to say verified-or-not-verified, it is perhaps meaningless to say "photons" and "electrons" exist.

Such labels are Unknowable without mechanisms in place to decide their truth and/or falsity, which is why there is no physics at the root of things, only philosophy (or metaphysics?).
posted by Blazecock Pileon at 2:08 PM on September 6, 2009


It is pitch black. You are very likely to have a tree fall on you.
posted by loquacious at 2:10 PM on September 6, 2009 [2 favorites]


why aren't they more concerned with accidentally pulling a divide-by-zero on reality or trying to resolve Pi to too many digits?

Because eventually it would wriggle its stumpy little legs long enough and flip back over on its own.
posted by carsonb at 2:12 PM on September 6, 2009 [6 favorites]


why aren't they more concerned with accidentally pulling a divide-by-zero on reality or trying to resolve Pi to too many digits?

Dude, happens all the fucking time. You know how many awesome universes are just *gone* now cause some multi-brained bozo figured out his universe couldn't exist? That's why we have the Irrationality Machine and Paradox Buffers and a rainbow of dimension-altering substances. Hell, comedy was *invented* to keep that problem contained.

In any case, don't come cryin' to me when you measure your reality and find it wanting. The unresolved is here to protect you.

I mean *sometimes* we've been known to introduce some hilarious logic-disability meme-weapons into a population as a way of preventing Pure Logic Destruction, but I'd never do that to you guys. Really.
posted by The Whelk at 2:15 PM on September 6, 2009 [4 favorites]


"If our small minds, for some convenience, divide this glass of wine, this universe, into parts — physics, biology, geology, astronomy, psychology, and so on — remember that Nature does not know it! So let us put it all back together, not forgetting ultimately what it is for. Let it give us one more final pleasure: drink it and forget it all" - Richard Feynman

All of these are different labels we give to communities of people and the theories about the world they develop. Physics is the name we give to the group that studies the most simple phenomena, the "things" out of which everything else we study are made.

What we talk about when we talk about a biological or political system system are the same things physicists talk about, just at a different scale. Whether it's desirable to restate our biological theories in physical terms is debatable on a case by case basis, but it's entirely conceivable that we could. There is just one world out there, after all.
posted by phrontist at 2:27 PM on September 6, 2009 [2 favorites]


Not to pileon, but you could make the argument that conceptions of things exist only while conceptualizers exist. As in, the universe doesn't exist in your head, your concept of the universe exists in your head. Take away all the conceptualizers, and all the conceptualizers' tools like labels go away too. Things outside of your head remain, but you were never labeling those things in the first place. You were labeling some memory you happen to have because of some reaction your eye had a second ago.

(But this argument ends in an infinite recurse...)

(And on preview, wow, I typed that slow.)
posted by ifandonlyif at 2:40 PM on September 6, 2009 [1 favorite]


What we talk about when we talk about a biological or political system

Coming soon, Raymond Carver's previously unpublished collection of thrilling sci-fi!
posted by aldurtregi at 2:43 PM on September 6, 2009


Fruny: I believe this is presented as a big deal because even if they have not produced actual magnetic monopole "particles", it still demonstrates their existence. That is, either the divergence of B is always zero, or some monopoles must exist. That that have managed to constrain an area of space to have a non-zero div-B is therefore significant.

I don't think that's what's happened here at all. ∇●B is still 0, and there's no suggestion from this experiment that "real" magnetic monopoles exist. What they have, AFAICT, are very very wiggly flexible bar magnets, whose ends therefore look a lot like monopoles.

Monopoles would fit very neatly into electromagnetic theory, and would have interesting and probably useful properties, not to mention cosmological implications, but my understanding is there's no solid evidence that they've ever been observed to exist and the current assumption is that they don't.

Doubtless this is an interesting discovery in condensed-matter physics or materials science but it's not the fundamental physical discovery that the confirmed existence of free monopoles would be.
posted by hattifattener at 4:02 PM on September 6, 2009


what are the practical applications of real monopoles?

Well, IF monopoles exist, and IF we can somehow catch and contain them (a VERY big second "if")...

Some prominent theories claim that monopoles can catalyze proton decay. That is, monopoles munch on the nuclei of any atom.

This would be totally awesome. Because tons of energy would be released. It'd be like fusion, but on anything.

So basically a monopole could be like the basis of a Mr. Fusion from Back to the Future. Pour in beer, monopole goes nom nom nom, cars fly.

Again, though, a very big IF up there.
posted by maschnitz at 4:55 PM on September 6, 2009 [1 favorite]


WolfDaddy: "Photon hits magnesium and gets it all excited.

So photons are abusers and magnesium is a masochist. Got it.
"

Who are you to call a consensual and mutually satisfactory chemical reaction abusive?
posted by idiopath at 4:58 PM on September 6, 2009 [2 favorites]


But electrons are just electrons, and have no life at all.

And yet quantum mechanics says we can't predict their behavior very well. Some people claim it represents free will, on a quantum basis. Still, it's a nice quote that demonstrates that biology and physics intersect, if that's what the favorites were about.
posted by pwnguin at 5:19 PM on September 6, 2009


Who are you to call a consensual and mutually satisfactory chemical reaction abusive?

Who are you to call a consensual and mutually satisfactory masochistic relation abusive?

Yeah, excite my PN junction! Hit me with your photons! Shine you slit experiment on me harder!
posted by loquacious at 5:23 PM on September 6, 2009 [2 favorites]


Ouch, my electrons! Hey, who invited flourine to the party? That guy is a dick.
posted by loquacious at 5:25 PM on September 6, 2009


Not endorsing this in any way...
posted by Jimbob at 5:48 PM on September 6, 2009


Oh, monopoles! So elusive with the giggling and the hiding behind trees. Anyhow, can someone make me a novelty shower curtain with Maxwell's Equations that only gives the answers once the water heats up enough? This erstwhile physics major says KTHX!
posted by unknowncommand at 8:42 PM on September 6, 2009


Apparently if magnetic monopoles exist then everything Larry Niven ever said is right and we get fertility boards, ringworlds, fusion ramscoop spaceships and sex with aliens.
posted by GuyZero at 9:28 PM on September 6, 2009


Who are you to call a consensual and mutually satisfactory chemical reaction abusive?

Okay, so what's the safe word? C55H72O5N4Mg??
posted by WolfDaddy at 10:39 PM on September 6, 2009 [1 favorite]


Aw. For a minute there I thought that they'd discovered fundamental particle magnetic monopoles. And then reality came crashing down like a thousand pounds of steel, yanked down by a powerful electromagnet. One with two poles.
posted by Mitrovarr at 1:04 AM on September 7, 2009 [1 favorite]


It's science pr0n

I just entangled my monopole all over my keyboard!
posted by chillmost at 1:34 AM on September 7, 2009


Blasphemer!!! Stone him !!!!!
posted by Twang at 1:40 AM on September 7, 2009


Without biological entities of certain intelligence, there would be nothing out there to label these ideas with the names "photons" and "atoms", and thus physics would evaporate into æther.

Which suggests there is no such thing as physics, only philosophy.
[emph. mine]

This suggests to me there is no such thing as philosophy, only neurology. (Which is a branch of medicine which is reducible to biology which is reducible to chemistry which is reducible to physics which is reducible to philosophy which is reducible to neurology which is a branch of medicine which is reducible to biology which is reducible to chemistry which is reducible to physics which is reducible to philosophy which is reducible to neurology which is a branch of medicine which is reducible to biology which is reducible to chemistry...)
posted by DevilsAdvocate at 5:37 AM on September 7, 2009


There is no such thing as science - there is only engineering.

It's all a damn waste of time till we find a use for it.
posted by vicx at 6:31 AM on September 7, 2009 [1 favorite]


Y'all be crazy. There is only one real thing. As it was, so it is, and so it shall always be. That is singularity. One. There is no outside or inside, only singularity. There are no particles. How can there be particles, when there is only one thing? Everything you think you see is illusion. You are an illusion. These words are illusion. Only singularity exists.
posted by Goofyy at 9:26 AM on September 7, 2009


loquacious: "boutique Hi-Fi shop?"

I can't find it but there was a piece in Stereophile eons ago (probably by Sam Tellig) stating that the most important property of speaker cable was the length, and that measurements showed output level is a step function of L.

posted by Rat Spatula at 9:42 AM on September 7, 2009


I'd Like to just say that this is the best, most enlightened forum thread I've ever had the privilege to read. I am very very glad I found this place.
posted by HalfJack at 11:15 AM on September 7, 2009


Anyone want to provide a book recommendation, or stanford encyclopedia of philosophy entry on the derail (Blazecock et al.)?
posted by kiltedtaco at 2:17 PM on September 7, 2009


Karl Popper
posted by Blazecock Pileon at 2:38 PM on September 7, 2009


Why all the hate for quasiparticles? I bet you people don't like phonons, either.
posted by fantabulous timewaster at 3:35 PM on September 7, 2009


When I studied the philosophy of science, we read Karl Popper (as Blazecok Pileon linked to above), Thomas Kuhn, Imre Lakatos (who doesn't have his own entry on stanford, but is discussed in the other bios), and Paul Feyerabend.

And, since relativism might come up, here is a link that will help you avoid that hole. In particular, the idea that perception is theory-ladden. (There's an old joke about somebody telling his professor about what a bunch of morons people must have been to think that the sun orbits the earth. And the professor replies, "Yes, but I wonder what it would have looked like had they been right.)
posted by ifandonlyif at 3:47 PM on September 7, 2009


loquacious: I see you over there with your TNT, trying to prove P=NP.

"P, NP / I'm dynamite!"
posted by Songdog at 8:37 PM on September 7, 2009


Everything that happens is physics. Chemistry and biology (and everything else, really) are sorts of applied physics, or a higher level language for describing what happens. No less a science, just different.
posted by gjc at 7:02 AM on September 8, 2009


And yet, the periodic table can't even be constructed using just physics, forget complex chemical and biological processes.
posted by vacapinta at 8:18 AM on September 8, 2009


The gross features of the periodic table are absolutely derivable from physics. Angular momentum comes in lumps. The electron orbit with no angular momentum has only one projection; the orbit with one lump of angular momentum has three projections; the orbits with n lumps have 2n+1 projections. Each electron has two internal angular momentum projections, and otherwise electrons exclude each other, so each orbital projection may contain up to two electrons. So what does the periodic table look like? There's a group of 2*1 = 2 columns, a group of 2*3 = 6 columns, a group of 2*5 = 10 columns, and a group of 2*7 = 14 columns, defined by the orbital angular momentum of the outermost electron. This is the chemically active electron, and its momentum says a lot about that atom's chemical properties.

Now, you have to do a calculation to determine when the different columns start filling. And things get messy for the heavy elements, where the innermost electrons start moving near the speed of light, and saying "an" electron occupies "an" orbit starts to be a bad approximation. You wind up talking about "quasiparticles" that account for the interaction between the valence electrons and their partners deeper in the cloud. But that's certainly doable. What mysteries of the periodic table are you thinking of, vacapinta?
posted by fantabulous timewaster at 9:33 AM on September 8, 2009 [2 favorites]


Yeah, I was thinking more about the relationship between atomic number (or, number of protons) and the atomic mass (or even just protons+neutrons). As far as I know, thats still an unsolved problem from a pure physics standpoint. Isotopes just are the way they are.

One of the exercises you do in most elementary quantum mechanics classes is to solve the Schrodinger equation for a Hydrogen atom. From there its not hard to see that solving it for a Helium atom, with two electrons, is pretty much impossible, at least without making some simplifying assumptions, like ignoring the effect any electron has on each other. For more complex atoms, forget it.

Nobody has proven that atoms like Iron with 32 neutrons should or do exist. We observe that they exist, chemists study their properties and then physicists sort of nod and say...yeah thats probably right.
posted by vacapinta at 10:12 AM on September 8, 2009


Actually, the table of isotopes is understood at a level comparable to the table of elements. There is a "shell model" that starts from the fact that protons and neutrons have the same angular momentum selection rules as electrons. So just as an atom with full s- and p-orbitals is hard to excite electronically, and behaves like an inert or "noble" gas, isotopes with full nucleon orbitals are "magic" and are much more tightly bound than their neighbors. There should be a magically hard-to-excite nucleus with two protons and two neutrons: this is helium, so tightly bound that it can form within and escape from heavy nuclei. There should be another one with 2+6 = 8 protons and neutrons, which is oxygen. It's the relative hard-to-excite-ness of the oxygen nucleus that means stars are powered by the C-N-O cycle, rather than by, say, an N-O-F cycle, since getting past O-16 takes a "hump" of extra energy. I think next magic number is 20, so apparently the second s-orbital (2*1 nucleons) and the first d-orbital (2*5 nucleons) fill at the same time.

You're absolutely right that the Schrödinger equation has exactly expressible solutions for the hydrogen atom, but not for the helium atom. But that doesn't mean that for a complex atom you "forget it." The tool of choice for nuclear structure (and somewhat also for atomic structure) is the Hartree-Fock approach, where you treat each electron or nucleon as a free particle moving against the average background of all of its partners. This lets you accurately compute the properties of great swathes of the table of isotopes --- hundreds of isotopes at a time. Is it "not just physics" since the interaction terms are computed from an average, rather than from all the combinatorially possible groups? Do you have the same complaint about thermodynamics?

Incidentally, iron-58 (26 protons, 32 neutrons) makes up 0.28% of natural iron. Most iron is iron-56, which is the last nucleus reachable by a chain of exothermic fusion reactions in a typical stellar environment. Iron-57 and -58 are formed by adding neutrons to iron-56, and the fact that iron-58 has abundance 0.28% (rather than 28% or 0.0028%) lets you make a statement about the number of free neutrons produced in the supernova(e) where the earth's iron was dispersed and the earth's heavy elements created.
posted by fantabulous timewaster at 12:31 PM on September 8, 2009 [4 favorites]


Biology, chemistry and all of the other materials sciences except for pure mathematics* descend from physics.

Don't have a dog in this fight (and am backing the fuck up as instructed), but it might be more correct to say the others ultimately rest on physics to explain them. Just as physics rests on...erk!
posted by Mental Wimp at 1:27 PM on September 8, 2009


Thanks fantabulous timewaster. I always believed that deriving the stable isotopes was a bit of black magic. That is, given an element of atomic number N, how many stable (half-life > day?) isotopes does that element have?

The Hartree-Fock approximation is new to me, which only points out that I should have taken a chemistry class in addition to my physics classes!
posted by vacapinta at 2:22 AM on September 9, 2009


Well, there is some black magic, but now you know part of the incantation.

Usually "stable" means a lifetime long compared with the age of the earth, since those are the nuclides you're likely to find in the dirt (like, say, potassium-40).

I'd consider everything I wrote physics, but that's just because I don't know any chemistry.
posted by fantabulous timewaster at 9:09 PM on September 9, 2009


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