Physicists War Over a Unified Theory 451
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.'"
Limiting factors (Score:3, Insightful)
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.
Re:We never really know anything (Score:2, Insightful)
what ?? perhaps you have some convoluted idea of proof. all the things you mention are theories, no proof was given. i agree there is something always more to discover, but why do you think we can disprove something then?
also, as a studying mathematician, i do believe that we can proove and disprove things absolutely. to think otherwise is incredibly naive given the relative success of humanity.
Re:We never really know anything (Score:5, Insightful)
Where knowledge is symbolized by the sphere's volume and the unknown by the sphere's surface. Therefore as knowledge grows, so does the unkown (although the volume grows faster than the surface, total wisdom will be never achieved.)
(or if the sphere is a balloon, science grows until it explodes
Actually... (Score:2, Insightful)
Special Relativity didn't supersede Newton's laws of motion.
They superseded the classical viewpoint that momentum was speed times a constant mass, but to his credit, Newton never made this claim. His students did. In modern form, F=dp/dt still works under SR.
They also superseded the Galilean transformations by the Lorenz transformations, but that was Galileo's problem, not Newton's.
I'm being picky because I think Newton gets a bad rap and doesn't deserve it for the laws of motion. They're still good. On the other hand, GR certainly does supersede Newton's law of gravity, and in that case the criticism is valid.
Re:natural laws hold true, but values do not (Score:5, Insightful)
What the physicists are measuring isn't the speed of light - it is the dimensionless constant alpha. Since alpha is dimensionless, you cannot renormalise changes in it by changing the size of your units. (Alpha is a measure of the strength of the electromagnetic (and electroweak) force.)
Quantum mechanics is the thing we know least about. We have tested general relativity to fourteen decimal places, but QED (quantum electrodynamics) has only been tested to ten decimal places. Quantum is a theory filled with ad-hoc rules. GR is increadibly simple. It wouldn't surprise me at all if quantum field theory was shown to be a suitable limit of what happens to gravational waves once non-linear effects become important, and once you start running into the effects of compactified dimensions.
Re:We never really know anything (Score:5, Insightful)
Today we know that general relativity and quantum mechanics don't work together, but we aren't sure how to fix it (though string theorists try hard).
Eventually it's conceivable that we'll write down some basic laws and then millenia will pass without any evidence that something is still wrong. While you're right that it's impossible to prove that these laws are correct, scientists are very diligent about trying to find holes and if none are found, then everyone will believe we finally know the truth. And perhaps we actually will.
Re:We never really know anything (Score:5, Insightful)
Mathematics is entirely artificial. It's based on rules and premises that we pretty much made up. You can prove things in math because it's a self-contained problem set, and you're looking at it from the outside with an omniscient view.
When you didn't invent the framework of the problem, it tends to be harder to prove a solution.
That said, you may never be able to prove a Unified Theory, because you can't ever be certain you've described every aspect of the problem set. But you can disprove a physical theory (or at least show it to be lacking) simply by finding a counterexample.
Re:natural laws hold true, but values do not (Score:2, Insightful)
(One second is how long a photon takes to travel a certain distance.)
Question: Seconds, as a unit of time, have been around far longer than the ability to observe photons, have they not? Has the concept of a second been redefined by physicists to mean the amount of time it takes a photon to travel a certain distance?
Not trying to be argumentative here, just curious. My knowledge of physics could fit in a thimble, with room to spare
Re:We never really know anything (Score:1, Insightful)
Whose being naive here. As a studying mathematician you should have taken enough about the physical sciences to know that the very basis of theories in physics is that nothing about them can be proven but it takes only one experiment to disprove them. As for mathematics since it is a language and doesn't have to stick to the laws of the Universe you can certainly "prove" different theories based only on logic or mathematical manipulation of your symbols.
Now having said that it doesn't mean that just because you can't prove a physical theory you can run around claiming that any theory is as good as the next. Disproving a theory in physics is simply the process of finding a phenomenon for which our current theory doesn't hold. In forming a new theory however it better reduce to the old theory in the absence of the conditions that produced the unexplained phenomenon. This is known as the evolution of science. Whole theories are not just discarded because they can't currently explain something. Even Einstein's greatest theories would have been impossible without the old theories as a guide.
Re:We never really know anything (Score:2, Insightful)
as a mathematician, i expect you are well aware of what happens when premisses are incorrect. also as a mathematician, i *hope* you are aware that because it is a logic system - a conceptual entity with no necessary binding to reality - mathematics is capable of 'proof'.
i urge you to take a few *good* classes (bad classes will be a waste of your time, perhaps independent study would be better) in epistemology. it may not change your mind, but it might change your mind.
in any case, i think it's rather naive to believe that our proofs accurately and precisely describe reality. to think otherwise is incredibly optimistic, given the relative success of humanity. (i mean, how hard is it for a species to survive? and how long have we been here? the odds are against us just as much as they are against the cockroach. our "knowledge" does not separate us from our ecology.)
we're trying to build working models of our environment, so that we may predict it with greater success. none of this implies proof, no matter how well it may seem to work.
Relativity doesn't describe particles.... (Score:2, Insightful)
General and Special relativity are theories of the large, describing gravity and the warping of space/time due to gravity.
Quantum Mechanics is the theory of the small, at the particle and sub-atomic level and it's a nasty dirty theory that has all kinds of exceptions and sepcial rules.
The problem in particle physics today is that you can't join Relativity and Quantum Mechanics without some nasty consequences, infinities, zeros and things that don't make much sense. Not that physisits haven't tried. The current merger of Relativity and Quantum Mechanics is the Standard Model. Which works but doesn't expain WHY it works.
The String theorists have a theory that does merge Relativity and Quantum Mechanics, and solves the problems of inifinities and zeros, however current string theory is only an approximation and isn't refined enough for experimentation yet. That is predictions from String Theory can't be tested in the lab at the energies that are available. Who knows you may only be able to test string theory with a big bang, and then look out everything starts over again.
Again, I'd be interested to see a piece on this in Scientific American or some other Science journal that can delve a little deeper into the solid-state theory and see where it fits between the Standard Model and String Theory.
I do wonder if the solid-staters look at things in 10 or 11 dimensions do they start looking like strings?
Re:Help (Score:3, Insightful)
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.
Re:Okay, Here It Is (Score:3, Insightful)
The most important point isn't whether there are emergent organizing principles at different levels, because everyone knows there are. The real arguments is whether or not "fundemental" particles are really real. The particle physics community believes they've got a grasp on the basic building blocks of reality, but then some solid state boys come along and offer a theory saying they don't really exist at the base of things.
Think of it this way. In the particle physicist mind, you don't need vacuum fluctuations to describe particles. They both have an independent existance. The solid state people have suggested that all particles are merely a consequence of the vacuum fluctuations. You can't have particles without the background.
While the two conflicting viewpoints do arrise from different philosophies, it also seems clear that there is an underlying truth. Either there are particles in full truth, or there is just a vacuum that makes it look like there are fully qualified particles. Ultimately it's the truth that's important, and this seems like an important difference to me.
Re:Creationists...We've been here before (Score:4, Insightful)
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...
Re:We never really know anything (Score:2, Insightful)
Re:We never really know anything (Score:2, Insightful)
Re:natural laws hold true, but values do not (Score:3, Insightful)
OK, first simple correction, actually, changing the speed of light changes the *distance* unit, not the time unit. We define time as cycles of a cesium atom, so the correct definition is that one *meter* is the distance light travels in some fraction of a second, per SI definition.
QED is the most well tested consistent theory that physics has ever seen. GR is not NEARLY as well tested as QED is. Blandly stating that QED has only been checked to 10 decimal places is crazy - QED is consistent to 10 decimal places with about 12 (if memory serves) completely different experiments. That's far more impressive than any test GR has undergone.
Alpha is the most well-known physical constant in physics right now, and suggesting that it changes, while it is possible, would not be in the least bit consistent with astrophysical findings. QED is more than consistent over well over several decades of orders of magnitude. GR doesn't win there at all.
QED is very simple, with absolutely *no* ad-hoc rules. The ad-hoc rules only come into play when
a) a physicist asks a meaningless question (What is the sound of one electron clapping?)
b) other forces come into play. You're talking about QED - that is, quantum *electrodynamics* - electromagnetism only, other particles/forces not invited! (Yes, this includes the weak force - otherwise QED would be quantum electroweakdynamics).
b) is to be expected, as a general unified theory doesn't exist yet, and a) is a simple extension of physicists who live in a macroscopic world trying to assign macroscopic ideas to a microscopic system (i.e. the 'location' of an electron). Any of Hund's rules could be seen to be ad-hoc as well, but a bit more theory and it all makes sense.
Now, if you mean the *Standard Model* is filled with ad-hoc rules, you're right. Neutrinos are all left handed... kindof. That sort of thing. That's correct. But QED is quite a solid theory.
GR is also anything but incredibly simple. It's simple only in the limit where you can take the interaction between two objects to be significantly greater than the Planck length, but anything smaller than that, and GR isn't so simple anymore. Simple reasoning: GR is continuous, QED is quantized. We can pull QED out from the quantized limit back to good old electrodynamics easily, but GR isn't nearly as lucky.
And, yes, I am a physicist as well, but I don't work in units where c is one.
Re:natural laws hold true, but values do not (Score:1, Insightful)
2) Sure, particles can travel no faster than c as far as we know. As far as Heisenberg goes with respect to this, you're talking out of your hat. No one knows how to reconcile quantum mechanics and relativity.
3) I have a BS in Mathematics and in Physics. I didn't see that it was pertinent, we should discuss the topic, not our credentials.
4) You think that it's scientifically accurate to assert that the passage of time is proportional to the speed of light? You just pointed out that we can't change the speed of light in a vacuum. Thus we can't experiment. Thus there is no scientific data. Thus any assertions about it are hot air. Also, think carefully about the precise statement I made. Do you really want to be in the position of defending that the rate of passage of time is directly proportional to the speed of light? Based on what evidence? I don't even know of any formulae that would begin to imply that. Conceivably, with a bunch of pontificating and hand-waving, maybe you could assert that the rate of passage of time was proportional to 1/(1-[d^2]/[c^2]) (where d is the 'new' speed of light) based on standard special relativity equations, but that would still be making shit up. And it's nothing like the statement to which you made your asinine reply.
Re:natural laws hold true, but values do not (Score:2, Insightful)
2. As numerous others have stated, quantum electrodynamics is entirely concerned with reconciling quantum mechanics with special relativity, and it works quite well. Both the uncertainty principle and special relativity are very important when describing particle interactions. It's general relativity and gravity that quantum mechanics doesn't get along with.
4. I never said proportional. Let's take the Planck time as a fundamental unit. The Planck time is proportional to c^(-5/2). If you make c smaller, the fundamental unit of time gets bigger, and everything takes longer, i.e. time passes more slowly. The change isn't the same for all processes, but that's because the relative strengths of forces also depend on c.
Re:FTL? (Score:3, Insightful)
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.
Re:Creationists...We've been here before (Score:2, Insightful)
> conclusively proved the lack of the cosmic
> ether, and Newton was kicked to the gutter
> (as an explanation for sub-macroscopic events)...
Sorry to nitpick, but this just isn't true. I did a research paper over these experiments and found that much of what many people believe about these experiments is simply wrong.
When the first experiments were done, everyone simply accepted that the accuracy of the experiment was compromised by any of the numerous obstacles the experimenter had to overcome. Even after the experiment was repeated several times, most dismissed the results as untrustworthy. Miller, who performed the experiment various times, actually DID find a postive ether drift. (Though he later admitted his experiment may have been flawed.)
The point is, no one considered these results as "disproving" classical physics until after Einstein had presented his theory. Thus, the ether drift experiments did not kick Newton to the gutter, but only served as a hindsight demonstration of what everyone had by then come to accept.
Like most theories, relativity did not gain unanimous favor over night. Instead the shift took place slowly. To suggest that the results of a single experiment could absolutely convince scientists that what they had come to accept without offering an alternative theory makes no sense. After all, no generally accepted scientific theory becomes wrong until something different becomes right (see Kuhn).
I'm sure this is all irrelavent to the point you were making, but what kind of
By the way, you can read my paper here [psiolent.com].