Physicists Postulate Existance of New Particle

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."

Comments

Intel Outside!

[NanoGator]

"University of Washington physicists postulate the existence of a new particle called the acceleron which links dark energy with the neutrino."

Acceleron... Neutrino... and it represents a particle whose value cannot be scientifically measured today. How about Itanion?

okay everybody has to do this at last once...

[shaitand]

I for one welcome our new dark energy overlords!

So...

[shfted!]

Acceleron is to neutrino, as Celeron is to Centrino. Suddlenly, accelerons sound like old news.

Subatomic particles are like programming languages

[HotNeedleOfInquiry]

There's a zillion of them, of which only about 4 are of any use to most of us...

An acceleron?

[Cecil]

I've got acceleron in my computer.

Woohoo, that was the worst pun ever! Someone shoot me.

What?

[Dausha]

Is it just me, or are scientists trying to make science fit the theory? I mean, once upon a time people thought the Sun revolved around the Earth (now we all know the Universe revolves around me), and kept coming up with more and more complicated explanations regarding why the other planets retrograded. Finally, somebody had the balls to say that the Earth revolves around the Sun (but, based on my parenthetical statement above, he was still wrong).

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?

[black mariah]

Is it just me, or are scientists trying to make science fit the theory?

It's just you. Scientists come up with a theory, then try to find out whether it is true or not. What you're describing is best referred to as pseudoscience, willfully bending facts and evidence to support one's own version of the truth. This is not real science. This is not trying to come up with an explanation to a problem. This is the equivalent of a conspiracy theorist being presented with papers that refute one of his theories, then writing those papers off as PART OF the conspiracy. It's idiocy at its finest.

Re:What?

[Alsee]

as I understand it, we have an assumption of science that requires that we account for mass that is not present. Voila! Dark Matter

You have it backwards. They are trying to account for matter that apparently *is* present, we just can't see it and don't know what it is.

There is lots of evidence that there is *something* there, we can see its gravitational effects on the stuff we can see. Gravitational lensing and orbital speeds. And there's plenty of other evidence I don't know offhand.

If you can somehow explain all of the evidence without "dark matter", well you'll be almost as famous as Einstein.

-

Re:What?

[hcdejong]

No. It's always a matter of trying to make the theory fit your observations. Adding stuff to the theory, and then trying to prove or measure that addition is a perfectly valid way of working.
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:What?

[ghostlibrary]

"Is it just me, or are scientists trying to make science fit the theory?"

It's neither :) The main thing is, when faced with a problem in the current theory, the scientists are saying "Okay, maybe it's _X_"-- but they make sure _X_ is testable.

That's what keeps it from just being pseudoscience or fiction. As long as a theory is testable, it can be as wacky as you want.

Subject to the usual criteria and Occam's Razor, of course-- really wacky ideas (like 'the Big Bang' or 'Sun is center of solar system') take a little time for the advancements needed to test them.

Dark Matter may be a hack or totally wrong, but at least it's well-defined and _testable_. Alternative theories (like a modified gravity law or a new particle type) are equally wacky and equally testable. I can't wait to see which wins!

Re:What?

[nine-times]

GP: Is it just me, or are scientists trying to make science fit the theory?

P: It's just you. Scientists come up with a theory, then try to find out whether it is true or not. What you're describing is best referred to as pseudoscience...

Well, then Mr. Smarty-Pants, I guess the question then is whether most people who describe themselves as "scientists" are, in fact, scientists, or are they "pseudoscientists"?

I mean, it seems like that's the question the OP was asking. Are these "scientists" making a theory to fit the physical world we live in (which would be proper), or are they making up imaginary particals so they can pretend the physical world we live in fits their theory? It's a good question.

Re:What?

[nine-times]

You have it backwards. They are trying to account for matter that apparently *is* present, we just can't see it and don't know what it is. There is lots of evidence that there is *something* there, we can see its gravitational effects on the stuff we can see. Gravitational lensing and orbital speeds. And there's plenty of other evidence I don't know offhand.

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:What?

[Ayaress]

Much as I have a rule againt replying to posts that resort to insults, I always end up doing it.

Your problem comes from the fact that you, like so many other people, insist on a ass-backwards concept of how science works.

These scientists are not creating a theory. You don't have a theory unless you have observation to base it on.

They're making a hypothesis, which is just that - a hypothesis. They throw out a few ideas that give them some inkling of what to look for. It doesn't tell us anything, but it grows out of things we already know.

Then, they go to the observation, and try and see what there actually is. You don't need a hypothesis to do observation, but with extremely complex stuff like this, it's a good idea to know what you're looking for first, or you'll be hit with information overload. They've already got a few thousand particles on the books, so if they don't have an idea of a new one they're looking for, they'll never find it underneath all the protons and electrons and pions and morons. If the observations fit the hypothesis, they start throwing it all into equations.

When they derive equations that hold true, it becomes a law. Law still doesn't really tell you very much. So e=mc^2. It doesn't tell you anything useful about mass or energy.

Theory is the highest level of scientific understanding, and is not just far above theory, but it's actually higher on the scale than law (which is why the "If it was true, it wouldn't be a theory anymore, it would be a law" is wrong. You go from hypothesis to observation to law and lastly to theory).

It comes after you've made your hypotheses, observed confimation, and derived laws from the observation. Theory tells you WHY your hypothesis worked (or didn't, as they case may be), and why the laws do what they do. All the fancy things you can read out of e=mc^2 (like mass being variable, energy and matter being interchangeable, and so on) are Theory. Theory outranks law.

All we have here is hypothesis, nothing more. You're trying to equate hypothesis with theory, but they're completely different things, separated by two levels of understanding.

Re:What?

[ekuns]

Are scientists being close minded and protective of their current understanding, and plowing ahead on a path that they should, within reason, be able to predict is heading the wrong way?

I'm a particle physicist by training (although not by career). The answer to this question, IMHO, is "No." Most particle physicists I know -- of many dozens -- would prefer to find something that the current standard models clearly cannot explain. The problem is that with only a few tweaks, so far, the current standard model is been able to predict just about every measurement thrown its way, and with a dismaying degree of accuracy.

See, here's the problem. The standard model of particle physics accurately predicts all measurements made thus far to as much accuracy as people have been able to bring the calculations. Many consider the standard model to be quite ugly because it has so many "arbitrary" parameters with no underlying theory of where those values come from: It has about 20-ish measured values that go into it. Many of those arbitrary values are the measured masses of particles, and the measured interaction strength of the three forces (not including gravity).

All of the physicists I know and most of the physicists I've ever met in the particle physics field are quite willing to be pursuaded by a new theory, but no such theory has presented itself. Some have thought that string theory will be that paradigm shift, but so far there is not enough evidence to prove or disprove.

When a convincing quantum theory of gravity appears, that will probably fix many of the complaints people have about the standard model.

So the issue at hand here is some scientists who are making a hypothesis within the current framework, extending the current framework, to explain some seemingly unrelated measurements. This is not epicycles on top of epicycles, although it might appear as such.

From reading the article, it appears that this hypothesis is disprovable, and thus a strong scientific hypothesis. It will be interesting to see how this theory holds up against evidence.

Re:What?

[ekuns]

I guess you wouldn't believe me if I told you I knew more than might be immediately obvious

I hadn't yet made any assumptions about what you do or do not know. I aim to make as few assumptions as I can, because assumptions are so frequently incorrect.

And yes, many of these people I have in mind are even "scientists" by trade.

I'm open to believing this. I have definitely encountered some "true believers" in physics and in other sciences. Most of the people I know and knew did not fall into that camp, but there's a selection there because I tend to find "true believers" annoying. Because by definition they are not open to evidence.

I have changed my mind on major scientific issues several times during my life. I expect I will do so on major theories at least a few more times. I certainly hope so! The alterntative is boring! Personally, I hope that they do NOT find the Higgs Boson. It will be much more interesting if they do not find it, because it is getting more difficult with time to construct a theory that can explain why we haven't found it. If the Higgs Boson is not found in the next decade, that will have serious consequences for many current theories.

Along with that, I will say that very few of non-believers I know would say that quantum machanics "makes sense".

I understand what you are saying. But quantum physics really does make sense. It's just not intuitive, because our experience with the macroscopic world does not correlate well with the behavior of very small things. You're right in that I give huge value to a theory that predicts accurately, and that I value more highly a theory with predictive power than a theory with less predictive power that is more understandable.

To a point. Adding epicycles upon epicycles blindly can become an obsessive exercise in not looking elsewhere. The good news is that lots of physicists are looking strenuously for alternative theories. Practically all of these theories get disproven within a few years, but eventually, someone will find a cleaner more beautiful theory than the current standard model -- I hope! -- that has the same or better predictive power as the current model.

The big philosophical question once the math works is -- what does the math mean? Many physicists happily totally ignore that question and just rely on the predictive power. Some other people get the accuracy of prediction confused with the concept of whether the theory or model is "true." Hey, it's just a model! No-one I know thinks that the current theory is the end of the road. What does the math mean? That is an excellent question. I am hoping for a new theory that explains at least some of the following questions:

Why three dimensions of space, and not two or four? (I'm ignoring any "curled up" dimensions which we cannot participate in.) Why do the particles we know of have the masses they have? Are space and time continuous, or discrete? What causes mass to exist? Why three "generations" of quarks and leptons, and not two or four? Is there a reason that the (observable) universe has the amount of energy that it does, and not less or more?

Re:What?

[edgar_is_good]

Gravitons are massless (although Kaluza-Klein gravitons are not), so plain gravitons would make bad dark matter as they wouldn't clump and don't redshift appropriately.

Also, to radiate gravitational energy, there has to be matter on the other brane (e.g. dark matter).

I find it funny that you appeal to string theory because you don't like new particles. The thing with string theory is that it predicts a huge number of unseen particles, some of which could be dark matter and accelerons. You can't really take the string theory without new particles.

Hello /. Editors.

[pb]

It is spelled 'existence'; it's even correct in the article body. So please fix it in the title.
Thank you.

When?

[PedanticSpellingTrol]

As soon as the next Copernicus, Newton, Einstein, Planck or Hawking comes along. Considering the exponential population growth lately, and assuming a fixed ratio of paradigm-defining supergeniuses to the general population, we're probably overdue.

Re:When?

[selderrr]

yes, i find it fascinating indeed that a paradigm genius hasn't show up in the past 30 years. Or at least not on a scientific level with global implications... Has our science grown so specialised indeed ? Copernicus, Newton and to a certain degree also einstein & planck were universal scientists. Modern day scientists work themselves deeper & deeper in smaller and smaller subfields of an allready tiny science topic... Could it be that we are killing global paradigms ?

Re:When?

[jamesh]

It has been proposed that the sum of the intelligence of mankind is a constant. Lets just hope this isn't true, 'cos the population is increasing rapidly.

Re:When?

[Oddly_Drac]

"Could it be that we are killing global paradigms ?"

Nope, it's just that paradigm shifts seem a lot more obvious in retrospect once development has followed a decent amount of testing. It could be argued that we're currently in the grip of a paradigm shift that's affecting society as a whole, given that global, affordable communications have really started to take off in the past 20 years.

On the other hand, there isn't a lot of 'pure' research being undertaken, which means that you're limited to the postgrad, postdoctoral academic work these days.

Re:When?

[Daniel Dvorkin]

I think part of the problem is that there is just so much to learn before you can make meaningful new contributions in just about any field that becoming a "universal scientist" these days would require more time than most people get. It generally takes a minimum of ten years of university experience -- four years undergrad, four to five years grad, one or two years postdoc -- to start a scientific career in any one, specialized field. People can, and sometimes do, get two PhD's in different fields (usually closely related ones, e.g. math and physics) but realistically, if you want to have any time left for research after that, that's about it. Being a "natural philosopher" who makes great advances in, say, math, physics, astronomy, chemistry, biology, and engineering -- all in one lifetime -- is pretty much impossible these days, because most of the work that's possible for gifted amateurs has already been done.

Hmmm

[advocate_one]

observations don't match your theory???

postulate a new particle...

how about working on the existing theory so that it doesn't require yet another particle???

Re:Hmmm

[Oddly_Drac]

"how about working on the existing theory so that it doesn't require yet another particle???"

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?

Re:Hmmm

[div_B]

The history of physics is full of theorized particles or fields that never panned out. We just never read about them in textbooks, because who wants to learn things that are wrong. We tell glamorous annecdotes about the hard to find particles that were discovered (e.g. Neutrino) and ignore the theories that were failures (e.g. Ether). So, our perceptions are colored, and we over-value theory.

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... %

Re:I postulate the existence of...

[hdparm]

Surely, you could use some of these accelerons.

Re:Curiouser and Curiouser

[erik_norgaard]

There are dectectors that do detect something which is generally accepted as being neutrinos.
The interact very weakly, has an energy less than 29 eV and travel close to the speed of light.

Since they interact so weakly they can be used to detect supernovas before the supernova is visible on the sky.

The problem is that the sensitivity of the current detectors does not allow to determine wether these has a mass and travel a little less than the speed of light or if they are massless. Neutrinos with mass can resolve the dark energy problem.

Another problem is that the detectors does not detect the amount of neutrinos to be expected.

Not always bad

[levell]

Speaking as someone who has predicted new particles 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....

Writers from ST:Voyager

[wowbagger]

Does anybody else get the feeling that the writers from Star Dreck:Voyager have moved into the particle physics business?

This just reeks of the "Particle of the Week" writing that ST:V indulged in so frequently.

What next - the hypothesis that the universe will undergo a "Big Rip", but then the interaction of the accelerons and the whetions will reset the timeline and everything will be back to normal?

Testable..

[kettlechips]

"This is the only model that gives us some meaningful way to do experiments on earth to find the force that gives rise to dark energy. We can do this using existing neutrino experiments."

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!

[Xentax]

I actually RTFA (no, I'm not new here...), and I think the submitter is wrong about one thing.

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.

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

Neutrinos.

[Christopher Thomas]

The problem is that the sensitivity of the current detectors does not allow to determine wether these has a mass and travel a little less than the speed of light or if they are massless. Neutrinos with mass can resolve the dark energy problem.

Actually, it's the dark _matter_ problem massive neutrinos address, and they only form part of the puzzle ("hot dark matter").

Dark _energy_ appears to be a repulsive force intrinsic to space. This proposed model is one take on a mechanism for it.

Neutrino mass has also been pretty conclusively demonstrated by observations of neutrino _oscillation_ (changing of flavour), which cannot occur if neutrinos are massless. This incidentally also solves the solar neutrino problem (the detectors producing shortfall measurements could only detect one type of neutrino, while solar neutrinos were oscillating between all three types in transit, resulting in many not being detected).

Most of these developments happened within the last decade or so. We're in a very interesting time for particle physics (between new observations, new mathematical approaches to applying string theory, and new approaches to modelling gravity that aren't string theory).

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