Slashdot Mirror
Physicists War Over a Unified Theory
beggs writes: "I was looking through the New York Times and came across an article which talks about a new front in the war to find a unified theory, but this one does not come from the particle physicists, it comes from the solid state physicists. Here is a little quote for wet your appetite: 'some solid-state physicists are trying to show that the laws of relativity, long considered part of the very bedrock of the physical world, are not platonic truths that have existed since time began.'"
So I think it's very good that these scientists are challenging theories like this.
It is narrow thinking to propose that we ever have the "final" answer because there is no way to prove that something is right. We can only prove that things are wrong.
Newton thought he had it covered, and the world agreed. Then Einstein came along and shook our understanding in strange ways. People got comfortable, then Schroedinger and his damn cats show up and screw things up again. Then we get comfortable. Then scientist discover that we still do not have whole story yet again.
Don't you get it? The wonderfulness of it all is that we will never know it all. The beauty of creation is that we will always have something more to discover.
--- -- - -
Give me LIBERTY, or give me a check.
Absolutely. Einstein's theories superseded Newtonian physics, though Newton's system works just fine for most things here on Earth. It's only when one approaches the speed of light that you find the discrepancies pointed at by Relativity -- and discover how matter and energy interrelate.
Einstein's work may also not adequately describe the universe in some instances; it cannot satisfactorially explain how the universe came into being. A new theory that can do so can hopefully be found -- and if it is, it will very likely teach us new things, things that may affect our every day life, just like Einstein has.
Arguing with theory (especially Relativity) is not uncommon. The only way theories become so well supported is trial by fire.
I'm all for arguing with the theory, but more interested in the result.
Since we are talking Unified theory, please allow a shameless plug to my fav String Theory site.
Good quote, too many chars. Seriously, the slashdot 120 char limit sucks!
Challenging Particle Physics as Path to Truth
By GEORGE JOHNSON
n science's great chain of being, the particle physicists place themselves with the angels, looking down from the heavenly spheres on the chemists, biologists, geologists, meteorologists -- those who are applying, not discovering, nature's most fundamental laws. Everything, after all, is made from subatomic particles. Once you have a concise theory explaining how they work, the rest should just be filigree.
Even the kindred discipline of solid-state physics, which is concerned with the mass behavior of particles -- what metals, crystals, semiconductors, whole lumps of matter do -- is often considered a lesser pursuit. "Squalid state physics," Murray Gell-Mann, discoverer of the quark, dubbed it. Others dismiss it as "dirt physics."
Recently there have been rumblings from the muck. In a clash of scientific cultures, some prominent squalid-staters have been challenging the particle purists as arbiters of ultimate truth.
"The stakes here are very high," said Dr. Robert B. Laughlin, a Stanford University theorist who shared a Nobel Prize in 1998 for discoveries in solid-state physics. "At issue is a deep epistemological matter having to do with what physics is."
Last year Dr. Laughlin and Dr. David Pines, a theorist at the University of Illinois and Los Alamos National Laboratory, published a manifesto declaring that the "science of the past," which seeks to distill the richness of reality into a few simple equations governing subatomic particles, was coming to an impasse.
Many complex systems -- the very ones the solid-staters study -- appear to be irreducible. Made of many interlocking parts, they display a kind of synergy, obeying "higher organizing principles" that cannot be further simplified no matter how hard you try.
Carrying the idea even further, some solid-state physicists are trying to show that the laws of relativity, long considered part of the very bedrock of the physical world, are not platonic truths that have existed since time began.
They may have emerged from the roiling of the vacuum of space, much as supply-and-demand and other "laws" of economics emerge from the bustle of the marketplace. If so, then solid-state physics, which specializes in how emergent phenomena occur, may be the most fundamental science of them all.
"We're in the midst of a paradigm change," Dr. Pines said. "Ours is not the prevailing view, but I think it will turn out to be the one that lasts."
Working in this vein, one of Dr. Laughlin's Stanford colleagues, Dr. Shoucheng Zhang, recently was co- author of a paper suggesting that elementary particles like photons and gravitons, the carriers of electromagnetism and gravity, might not be so elementary after all -- they might emerge as ripples in the vacuum of space, bubbling up from the quagmire in a way that can best be explained in terms of solid-state physics.
"The idea is of course crazy, thought provoking, and somewhat anti-establishment," Dr. Zhang said. "The main idea is to apply concepts from solid-state physics to answer some big questions of the universe."
The particle physicists insist that there is plenty of mileage left in their own approach. "I strongly believe that the fundamental laws of nature are not emergent phenomena," said Dr. David Gross, director of the Institute for Theoretical Physics at the University of California at Santa Barbara. "Bob Laughlin and I have violent arguments about this."
After hearing Dr. Zhang describe his theory at a seminar last month, Dr. Gross deemed it "an interesting piece of work." He said he found the mathematics "beautiful and intriguing, and perhaps of use somewhere."
That may sound like faint praise, but the particle physicists have reason to be wary. The squalid-staters are challenging them in a debate over how the universe is made and how science should be done.
Following the method of Plato, the particle physicists are inclined to see nature as crystallized mathematics. In the beginning was a single superforce, the embodiment of an elegant set of equations they call, only a bit facetiously, the theory of everything. Then along came the Big Bang to ruin it all.
The universe cooled and expanded, the single force splintering into the four very different forces observed today: electromagnetism and the weak and strong nuclear forces, which work inside atoms, are described by quantum mechanics and special relativity. The fourth force, gravity, is described by an entirely different theory, general relativity.
The particle physicists' ultimate goal is "grand unification" -- recovering the primordial symmetry in the form of a single law -- a few concise equations, it is often said, that could be silk-screened onto a T- shirt.
This approach, in which the most complex phenomena are boiled down to a unique underlying theory, is called reductionism.
The problem, the solid-staters say, is that many forms of matter -- ranging from the exotic like superconductors and superfluids to the mundane like crystals and metals -- cannot be described in terms of fundamental particle interactions. When systems become very complex, completely new and independent laws emerge. "More is different," as the Nobel laureate Philip W. Anderson put it in a landmark paper in 1972. To the solid-staters, it would take something the size of a circus tent to hold all the equations capturing the unruliness of the physical world.
Like Aristotle, they lean toward the notion that it is the equations that flow from nature instead of the other way around. Mathematics is just a tool for making sense of it all.
"For at least some fundamental things in nature, the theory of everything is irrelevant," declared Dr. Laughlin and Dr. Pines in the Jan. 4, 2000 issue of The Proceedings of the National Academy of Sciences. "The central task of theoretical physics in our time is no longer to write down the ultimate equations but rather to catalog and understand emergent behavior in its many guises, including potentially life itself."
There may not be a theory of everything, they say, just a lot of theories of things. This is exactly the kind of squalor the particle physicists abhor.
Dr. Grigori E. Volovik, a solid- state physicist at the Helsinki University of Technology in Finland, champions an idea he calls "anti- grand unification." In a review article last year (xxx.lanl.gov/abs /gr-qc/0104046), he ventured that the universe may have begun not in a state of pristine symmetry but in one of lawlessness. The laws of relativity and perhaps quantum mechanics itself would have emerged only later on.
The notion of emergent laws is not radical in itself. A flask of gas consists of trillions of molecules randomly colliding with one another. From this disorder, qualities like temperature and pressure emerge, along with laws relating one to the other.
So take that idea a level deeper. Physicists now believe that the vacuum of space is, paradoxically, not vacuous at all. It seethes with energy, in the form of "virtual particles" constantly flitting in and out of existence. So perhaps, Dr. Volovik suggests, even laws now considered fundamental emerged from this constant subatomic buzz.
Solid-state physics offers clues to how something like this might occur. The atomic vibrations that ripple through matter are, like all quantum phenomena, carried by particles -- called, in this case, phonons.
Just as photons carry light and gravitons carry gravity, phonons carry the subatomic equivalent of sound. Like bubbles in a carbonated beverage, phonons -- physicists call them "quasi particles" -- appear only when the medium is disturbed.
In the world of solid-state physics, quasi particles abound. In some substances, like the semiconductors used to make computer chips, the displacement of an electron leaves behind a "hole" that behaves like a positively charged particle. An electron and a hole can sometimes stick together to form a chargeless quasi particle called an exciton. Other such ephemera include magnons and polarons.
Evanescent though they are, quasi particles act every bit like elementary particles, obeying the laws of quantum mechanics. This has led some mavericks to wonder whether there is really any difference at all. Maybe elementary particles are just quasi particles -- an effervescence in the vacuum.
Particularly intriguing is a phenomenon, occurring at extremely low temperatures, called the fractional quantum Hall effect. In certain substances, quasi particles appear that act curiously like electrons but with one-third the normal charge. (Dr. Laughlin won his Nobel Prize for a theory explaining this.)
Quarks, the basic building blocks of matter, also carry a one-third charge, a coincidence that has fueled speculation that emergence may be somehow fundamental to the very existence of the physical world.
A stumbling block to carrying this idea further has been that the quantum Hall effect seems to work only in two-dimensions -- on the surface of a substance. But in a paper published in the Oct. 26 issue of Science, Dr. Zhang and his student Jiangping Hu showed how to extend the phenomenon. In their scheme, the physical world would be a three-dimensional "surface" of a four-dimensional "quantum liquid" -- an underlying sea of particles that can be thought of as the vacuum.
Analyzing the ripples that would appear in such a medium, the two scientists were surprised to find that they mathematically resembled electromagnetic and gravitational waves. But there are problems with the model. At this point, the hypothetical photons and gravitons that emerge from the equations do not interact with other particles, as they do in the real world.
"The coupling is zero, so apples are weightless, as is everything else," said Dr. Joseph Polchinski, a string theorist at the University of California at Santa Barbara, who recently discussed the model with Dr. Zhang.
And there is what the theory's inventors concede is an "embarrassment of riches" -- the equations predict hordes of exotic particles that do not exist.
"The hope is that some modification of the theory, not yet specified in detail, will remove the extra fields and turn on the coupling," Dr. Polchinski said. "Whether this can be done is at this point a guess. Overall my attitude now is interest with a high degree of skepticism."
If the theory can be made to work, it may point to a new way of unifying quantum mechanics and relativity. But Dr. Zhang is careful not to oversell what he considers a work in progress.
"Our work only made a tiny step toward this direction," Dr. Zhang said, "but it seems to indicate that the goal may not be impossible to reach." At the very least, he said, his work may inspire more collaboration between particle physicists and solid-staters.
Ultimately, though, the two sides know that they are talking across a divide. Taken to its extreme, emergence suggests that all the fundamental laws, even quantum mechanics, may be secondary -- that at the base of reality is random noise.
Dr. Polchinski said he found that idea discouraging.
"To me, the history of science seems to be a steady progression toward simpler and more unified laws, and I expect to see this continue and to contribute to it. Things may take many surprising twists and turns," he said, "but we reductionists are still quite happily and busily reducing."
--
It sounds a bit like the argument between Java and Perl to me :) There are those who believe that things that are clean and orderly are "right" and there are those that believe things that are loose and flexible are "right". (There are those that believe that life here began... out there...)
;)
In any case it's an interesting path to explore. I lean towards the loose and flexible side myself. If you saw my code you'd be able to tell
I am I the only one, but is anyone else worried that when they finally find the unified theory, "The Theory that Explains Everything," that it'll wind up being Murphy's Law?
"Prepare for the worst - hope for the best."
General Relativity orders a positive charge, but comes under fire from ballistic missiles. It's time for a negative charge!
__
Do ya feel happy-go-lucky, punk?
IANAP (Physicist, naturally), but I'd have to say that the solid-staters argument makes sense. It seems arrogant to think that the universe must obey these silly little laws we come up with. Mathematical laws are a tool, they simpify the workings of the universe so a human mind can grasp them. But they are not the universe. I would tend to agree with thier arguement that as systems get more complex, new rules come into play. How then can the universe's intricate workings be summed up in a few silly little equations?
.
I've found the answer! The universe isn't dominated by some elaborate unified theory, or general relativity, or quantum mechanics, or anything like that. I've found a principle that applies everywhere. Everywhere I look, there it is. The central principle of the universe is: STUPIDITY! It all makes sense now . .
Well, at least its the central principle in my life,
-- If any of the above made sense, I assure it was purely by accident.
Speaking as part of the community, the physics world is not at all portrayed accurately in this article. Nearly every physicist sees value in every subset of physics. Think nuclear physics is dead? I happen to know a few nuclear physicists who are still active in research. No-one I know refers to solid-staters as "squalid-staters". There is worthwhile research still in every discipline of physics, even solid state and particle physics.
I think what we have here is a case of journalistic hype used to make the a mountain out of a molehill. I do not think that anyone can deny that there has not been advances in the understanding of any field.
Ciao
nahtanoj
All I can say is well DUH! I'm not expert, but I have read a few things about super string theory and have to say that it really is more elegant than the standard model, the theory that particle physists use. Just fom a cursory glance at this article it sounds like the solid-state folks are proposing something similar to the super stringers. That particles are at their root a function of space and how it vibrates.
What I'd really like to see is some comparison between this new theory and string theory (it could be in there I didn't read past what was posted here)
What if it is just turtles all the way down?
I mean, okay, most of us are at least a little arrogant. We're revealing the secrets of the Universe -- how could our heads not swell, at least a little? But for most of us it's a little tongue-in-cheek, too.
Now the ideas in the article intrigue me. I'm in Particle Physics, and I was indeed under the impression that fundamental particles are, well, fundamental. The idea that this could all be quasi-particles ("effervescence in the vacuum" as the article puts it) like phonons (the sound equivalent of photons) in matter, is really cool.
I will agree with this much: there isn't enough discussion between the various disciplines. Scientists in general need to talk to each other more.
-Erf C.
Cthulu always calls collect...
For the first time on Pay-per-View, witness the tag team of
Dr. Robert "The Mad Doctor" Laughlin and Dr. David "The Towering Pine" Pines
take on the the duo of
Dr. "Stone Cold" Shoucheng Zhang and Dr. David "The Atom Smasher" Gross
in a no holds barred Battle Royale that will decide the FATE OF THE UNIVERSE!!!
A Cage Match is not enough to contain these fierce warriors when they collide -- the match will be the first Magnetic Containment Field match every held on Pay-per-View!!!
Order today for only $39.99, or $49.99 on the day of the event. Call 1-800-4GUTWAR to order. Thats 1-800-448-8927. That number again 1-800-4GUTWAR.
Sponsored by the CERN Particle Physics Laboratory, the Albert Einstien Relativity Foundation, and the King of Beers: Budwieser.
To expand on the previous explanation, as far as Plato is concerned there exists the universal idea of "chair". We may see isolated instances of "chairs", but the only reason we know these are chairs is because they are reflections or shadows of the universal (true, global, ) Chair.
I would suspect that most of us think the other way around: society has taught us to use the word chair, and now their is a general consensus of what a chair is. Thus the universal idea arises from the details. Plato would have argued that the details arise from the universal idea.
I remember reading an article some time ago in which a scientist proposed that Quantum Physics could actually be a natural corollary of General Relativity (where each particle is some kind of "ripple" in the space-time continuum), and that the mathematics of this could make sense if the requirement for Causality ("cause must happen before effect") were dropped from General Relativity.
His proposal suggested that quantum coupling (where two particles can become intertwined based on an earlier interaction) was caused by some kind of ripple-effect going back in time from the observed particle to the time that the original interaction happened.
He was able to explain many other aspects of Quantum Physics the same way, although he claimed that the mathematics was so complex that only the simplest of interactions had been formally proved to match between his model and QP - most of his theory, including the explanation of coupling, was hand-waving.
I always thought that this theory seemed one of the most elegant I've ever heard - no need to introduce new hypothetical particles like Strings, no need to assume that all the complexities of the Standard Model are fixed, absolute and arbitrary. Just take General Relativity, drop Causality, and look at what emerges.
I've often wondered whether this guy's theory ever went anywhere. It seems to have something in common with the theory proposed in this article - that QP is just an "emergent behavior" from GR. The difference is that the article seems to propose that there is no underlying rule at all except chaos and GR itself emerged from that; this guy proposed that GR was fundamental and QP was the emergent behavior.
Anyone know anything about this theory or know where the original article might be? Did this guy have any success or get any recognition? Has his theory been actually disproved, or simply ignored?
Stuart.
If only so many wars were fought so civily, with publication of papers, logic and reason taking the forefront over all that gun-use and wasted effort trying to convince people with a big stick.
Of course, on the other hand, there's always fighting wars with lawyers and tax-men. That qualifies as throwing papers and logic and math around, almost. Pseudo-logic and semi-science works great when you're dealing with human judges rather than mathematics.
"Look at me, I invented the stove!" -- Ben Franklin
In the late 19th century, Albert A Michelson, according to many the "Greatest" physicist of his time (and winner of the first Nobel prize in Physics (1907), decided to measure the speed of light...in 1878, he did so accurately for the first time, he was using about $10.00 of lab equipment, btw...his passion for accuracy and precision led to his teaming up with Edward W. Morley, in 1878 to prove the existence of the cosmic "ether", through the....
e du/lectures/michelson.html.....there's also a great page on Michelson here;....http://hum.amu.edu.pl/~zbzw/ph/sci/aam.ht m
Michelson-Morley Experiment. Michelson's career had been golden, and he was widely regarded as the best physicist of the 19th century. So, everyone "knew" that he would successfully prove the existence of the cosmic "ether", which would be the finally block in the edifice of Classical Newtonian physics...
instead, the experiment went completeley wrong, conclusively proved the lack of the cosmic ether, and Newton was kicked to the gutter (as an explanation for sub-macroscopic events)...
here's a link to a pretty good, non-technical account of this from U of Va....http://galileoandeinstein.physics.virginia.
In the 1950's, in the particle chambers of UCLA, strange traces were seen on the photograpic plates of particle collisions....physics of the time couldn't account for this particle, so the postdocs and the grad students waggishly nicknamed the unknown particle the "what-on", and many ignored it for over 20 years...
as instumentation and our undestanding of sub-nuclear particles became better, some other grad students, looking for new frontiers (and new dissertation topics), started researching the "what-on"...it has become....
The Quark and is now the center of the posh new "String Theory", which is yet another attempt to explain overall particle to particle interaction,and from the standpoint of "Classical Quantum Dynamics", Superstring theory kicks QD to the curb....here we go again.....
here's a good page on String Theory
http://superstringtheory.com/
the point being...these things we are discussing are so far beyond our abilities to directly sense or measure them, it's like the old story of the scientists examining an elephant in a lightless, closed room...
one scientist grabs the tail and thinks its a thin, long snake, another scientist grabs a tusk and thinks its a rhino, another grabs the trunk and thinks its a python...
since we have no ability to directly "view" or "measure" these things, we are using inference and deduction to provide us with our theories, yet as every generation of instrumentation improves and gives us new "information" we take that info and rework it...
face it, we could come up with a "Unified Theory" that completely explains our current "knowledge" about physics, to the satisfaction of 99% of the scientists on the face of the earth and....
it could be kicked over by some new experiment, just the way that Michelson-Morely kicked over "Classical" Physics...
Ten quid, she's so easy to blind. And not a word is spoken...
1) the various quantum tunneling experiments, where the Mozart 40th Symphony was transmitted through solid metal at several times the speed of light. There is a good link here. There was even a NOVA special or something on that (see that transcript here, - info about 2/3rds into the material)
2) maybe something involving the research of Steven Wolfram (developer of Mathematica), as seen in his forth coming book A New Kind of Science, which is very geeky, very bizarre, and right up this alley, and is supposed to be a rethinking of the very fundamentals of how science works. My head hurts already. This book is due for publication in January 2002, and is well worth pre-ordering.
"It is a greater offense to steal men's labor, than their clothes"
i never liked the big bang theory. it stinks of creationism. ... i'm no cosmologist. but the big bang stinks of creationism to me ...
So, let me get this straight. You are rejecting a reasonable theory which fits the observed behaviours simply because it conflicts with your religious (or anti-religious) beliefs?
Isn't that what people accuse religious folks of daily?
You aren't being logically consistant. You rail against anything with any hint of taint from our human experience, but at the same moment your rejection is based in how you feel about the existing theories. Stinks of creationism is a very visceral reaction to what you insist should be a completely rational debate.
Face it. You have a philosophy guiding your argument as well. That philosophy is Nihilism and your post stinks of it.
...The Cosmological Anthropic Principle. It has some nice discussion of how the symmetries we observe in particle physics might 'emerge' from low energy regimes of physical systems that are in some sense lawless. In general it's an interesting book that discusses why we have order in the universe quite a bit. But the part on order apparently emerging from a lawless universe seems to be what the current discussion is based on.
-- SIGFPE
If a solid-state physicist hits a particle physicist over the head with a tree that fell in the woods while nobody's around, we can finally get Schrödinger's cat out of that box...
Potato chips are a by-yourself food.
The reason this is forbidden is because of relativity of simultaneity. I don't know why this part of relativity is less well-remembered than the relativistic length-contraction and time-dilation, but it is really the key to almost all relativistic "paradoxes."
In any FTL travel, there are two events, A: leave the origin; B: arrive at the destination. FTL travel is believed to be impossible because observers in different inertial frames of reference would disagree about whether A or B happened first! Since it is paradoxical to arrive before you have left, the events cannot be causally connected.