Physicists Postulate Existance of New Particle 139
corngrower writes "University of Washington physicists postulate the existence of a new particle called the acceleron which links dark energy with the neutrino.
The theory offers an explanation for the recent discovery of the accelerating expansion of the universe."
What? (Score:5, Insightful)
Now, as I understand it, we have an assumption of science that requires that we account for mass that is not present. Voila! Dark Matter (or Energy, or whatever). However, since we cannot detect this new thing, we have to find a way to make that fit the mould. It seems to me that we are winding on-and-on down the rabbit hole. How long before there is a realization that this is just modern (or is it post-modern) retrograde theory?
Why does reality have to yield to theory? Can't it be the other way around? Do I have the karma to withstand a mod down?
Re:What? (Score:5, Insightful)
Re:What? (Score:5, Insightful)
Yes, sometimes a paradigm shift is needed. But that doesn't make the work done before it invalid. In fact, tracking the consequences of your current theory until you've painted yourself into a corner is a good way to find out if a paradigm shift is needed.
Of course, human nature makes adding stuff to a theory you already have a lot easier than coming up with a completely new idea.
Also, an entirely new theory will have to account for quite a lot. In this case, things like the components of an atom, the wave/particle duality, E=MC^2, etc, all of which took a century of work by the entire scientific community to figure out, will have to be explained by your new theory.
Re:Hmmm (Score:5, Insightful)
And if that particle actually exists?
There was a furor that surrounded the nuetrino when it was first thought up and they did think that it was so weakly interacting that they'd never find it. Turns out that several hundred tonnes of chlorine and some sensitive photodetectors embedded in a mountain do the trick.
The Higgs boson is another case in point; to find it in a collider requires extremely high energy collisions, but we don't have one. Do we write off the Higgs boson because we don't have a detector for it?
Not always bad (Score:3, Insightful)
Speaking as someone who has predicted new particles [arxiv.org] generally people come up with new model that do something novel (e.g. in the case of the paper I linked to, has a natural explanation of the relative electric charges of the particles.
If the model seems particularly interesting then people will do calculations in it and either show it's wrong or come up with experiments to test it....If it turns out to be right (if only....), then it's a good job you predicted those extra particles because you've just advanced our understanding of the way the world works. Even if it's wrong (likely!) the model might give someone an idea for a better one....
Testable.. (Score:2, Insightful)
At least this theory could possibly be proven or disproven right here on earth. That's what's nice about it.
Where it comes to hunting for clues concerning the evolution of the universe's expansion rate, or black holes/singularities (Now there's a gem of a postulated "particle"), you can freely conjecture with little chance of ever being proven empirically wrong (or right), as long as you account for whatever bits of information we're able to gather from 10.000(000.000) light years away.
They are NOT postulating! (Score:5, Insightful)
As far as I can tell, the existence of this new particle is being *hypothesized*, and since there's discussion of using neutrino detectors to see if they're right, it may soon be *theorized*.
A *postulate* is something else - a statement that is accepted as truth, usually as the basis of a theory or argument. Here's a helpful definition [reference.com].
I'm sure these people don't expect anyone to simply "accept as truth" the existence of accelerons, but rather want to go do experiments and turn their hypothesis into either a theory or a failed hypothesis.
A postulate is something along the lines of "Through a point not on a line, one and only one line can be drawn parallel to the given line."
That is, you can accept it as truth or deny it, but trying to actually prove or disprove it *experimentally* is difficult or impossible. There's either a logical counterexample, or not (or we haven't found it yet).
Xentax
Re:When? (Score:3, Insightful)
Re:What? (Score:3, Insightful)
It still illustrates his point. We measure activity that seems to be caused by strong gravity, but we can't account for it by the amount of matter that we can find in the universe, so we assume there are massive quantities of magical matter that we can't detect. Couldn't it be that our understanding of gravity is a little off, or this is being caused by something else we haven't thought of yet? Could it be our estimate of matter in the entire universe might be off somehow? Or, well, maybe we've decided on means of measurement (for any one of the variables) that don't work as well as we think. Or maybe our whole theory is off. Who knows?
But let's just assume it's magical matter we can't detect. [sarcasm] It's far more scientific than when people didn't understand gravity and assumed the planet were move by angels![/sarcasm]
Re:Hmmm (Score:2, Insightful)
For the love of Christ... Firstly, I think you'll find that most elementary courses in Special Relativity start with the assumption of the ether, and go onto discuss the Michelson-Morley experiment, the point being that one has to first understand the problems to be able to understand the solutions.
Similarly, Pauli introduced the idea of the Neutrino, since without it, beta decays can't conserve both energy and momentum. I'm sure that at the time introducing a new particle seemed alot less silly than abandoning these conservation laws, given that they had held true (with minor modifications due to SR) for about 300 years. Seems to me that he was right to do so, given the verification of the neutrino's existence decades later.
I took a course in atomic physics, and a fellow student couldn't understand the inclusion of the Sommerfield theory of electron orbits in the course. Again, it's always valuable to see the problems physicists faced at the time, and the valiant but failed attempts to solve them, and I expect that substantially more coverage of these theories is given than you seem to think.
Oh, please. You bring up a single example of a hard to find particle that was eventually detected, and use that to support the existence of the Higgs boson? That's not science, it's religion. The existence or non-existence of the Higgs boson will be determined experimentally, not by theory.
I think the problem here is largely the misconception that as particle physics has progressed, more and more particles have been added to the theory, and that the theories have become more and more complicated and ad hoc, ie, people think "HEP physicists already have 3000-odd particles to play with and now they're introducing a new one." This is not the case at all. Yes, as accelerator energies have increased, more and more particles have been found, but these are mostly composite particles. The situation before Gell-Mann and Zweig postulated the quark, was that there were many hundreds of new particles that had been discovered. The quark theory showed that all these particles could be constructed out of a few elementary particles. Furthermore the theory predicted new composite particles, and their characteristics with great accuracy (which were later verified experimentally). The point here is that modern physics has been for some time reducing the universe to simpler and more elegant symmetries and models. The fact that, as we have probed deeper both with theory and experiment, things have become simpler (though of course the mathematics used has become more heavy-duty), seems to be fairly good indication that HEP theory is on the right track, and if it isn't, that will become clear through experiment, and new theories will come out. That is to say, the scientific method will continue to do it's thing, as it has for hundreds of years, and progress will continue.
The accuracies of the predictions made by quantum mechanics and it's resultant field theories make it very hard to ignore, and mean that it has become very difficult to propose new theories which make the same predictions for lab experiments, fit with the ever-increasing volumes of astrophysical and observational-cosmological data, and at the same time remain self-consistant.
You can percieve the modern theories as attempts to preserve the models that have been built up to date, and you'd be right. I'd be less inclined to attribute this to arrogance and narrowmindedness, and more inclined to believe that it's because reality happens to concur with the theories to 99.99999... %