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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.'"

5 of 451 comments (clear)

  1. Re:We never really know anything by tijnbraun · · Score: 5, Insightful

    This reminds me of pascal's image of knowledge...
    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 :)

  2. Re:natural laws hold true, but values do not by Anonymous Coward · · Score: 5, Insightful

    This isn't quite correct. You are right that in changing the speed of light you are only redefining the time unit. (One second is how long a photon takes to travel a certain distance.) In everyday work, (yes- I am a physicist) I choose units where c is one. It makes things so much easier.

    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.

  3. Re:We never really know anything by dragons_flight · · Score: 5, Insightful

    You are forgetting something. Before the great paradigm shifts in the history of physics (Newton, Einstein, Bohr, etc.), there was always evidence that something was wrong with prevailing theory. Scientists on the front lines weren't "comfortable", they noticed things like the "ultraviolet catastrophe" and the precise spectra of atoms and knew something was wrong.

    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.

  4. Re:We never really know anything by dangermouse · · Score: 5, Insightful
    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.

    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.

  5. Re:Creationists...We've been here before by darkPHi3er · · Score: 4, Insightful

    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....

    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.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

    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...