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Physicists Identify Possible New Particle Behind Dark Matter
sciencehabit writes: Like cops tracking the wrong person, physicists seeking to identify dark matter — the mysterious stuff whose gravity appears to bind the galaxies — may have been stalking the wrong particle. In fact, a particle with some properties opposite to those of physicists' current favorite dark matter candidate — the weakly interacting massive particle, or WIMP — would do just as good a job at explaining the stuff, a quartet of theorists says. Hypothetical strongly interacting massive particles — or SIMPs — would also better account for some astrophysical observations, they argue.
I always thought that WIMP (Windows IIS MsSQL PHP) was the opposite of LAMP (Linux Apache MySQL PHP)?
If the force carriers for ordinary matter are called bosons...
Then would the force carriers for SIMPs be called...SIMPsons?
(T>t && O(n)--) == sqrt(666)
If you don't postulate some conjecture and start deriving all the required properties these particles are supposed to have, it's harder to find the proper experimental evidence you need to be looking for.
While everything you write is true, you leave out the actual importance of funding this: If SIMPS can be found, examination of their behavior in interactions would tend to prove or disprove fundamental ideas of the standard model.
That's my take on this all, anyway.
NB: I have been wrong before.
No one has "identified" anything. This is a paper with a proposal, an idea, a hypothesis. Behind it lie a rather gigantic pile of assumptions and parameters to fit the data. It's long been speculated that Dark Matter may not be simple, but rather could be as complicated as the visible spectrum (which contains electrons, photons, atoms, and the entire periodic table). But there's a huge problem with making predictions in a strongly interacting theory: you generally can't. "Strong interactions" mean that most computations do not converge. For instance we cannot, from first principles, calculate the mass of any atomic nuclei.
So this means the "dark matter sector" contains essentially a whole periodic table of stuff, and we're hopelessly unable to compute anything. This paper in particular ignores the possibility of bound states (e.g. atoms, mesons, etc) in the dark matter sector, which IMHO is just silly especially with strong interactions.
1^2=1; (-1)^2=1; 1^2=(-1)^2; 1=-1; 1=0.
So your postulation is that a theory which explains an enormous number of observations must be wrong because one group of observations... er, wait, what the hell are you saying?
The world's burning. Moped Jesus spotted on I50. Details at 11.
May I suggest a more generic name that doesn't have to be changed every five minutes?
Physically Interacting Massive Particles
The name will probably be shortened at some point.
I come here for the love
I understand the neutrino was theorized before discovery, but I just read the article and the chain of properties either WIMPs or SIMPs need to have, and they seem overly complex for something that there is no direct evidence for. Of course I am not a physicist. Just seems like we need better data collection of anomalous particle behaviors before investing much faith in such conjectures. Granted these theories could guide future experiments, but perhaps just sometimes theory gets a little too far ahead of experimental evidence.
Well, there is lots of evidence for something out there. This something, after coming up with other options and rejecting them through testing, must not interact with electromagnetic forces to a degree we can detect and have mass. Thus the "dark" and "matter". I am pa physicist and what you aren't seeing when you read these articles is a lot of math. It's complicated because physics at this level is really complicated and to come up with these hypothesis, they have to come up with something that fits what we already know about matter and the universe. That's going to involve a lot of graduate level mathematics and physics that describe a world that even physicists have a hard time wrapping their heads around. That's how particles get predicted, the math works out that way, and physics without the math is just philosophy. Sometimes you end up with something like string theory where the math works out (or seems to) but it can't be easily tested. At least these options can be tested.
If SIMPS can be found, examination of their behavior in interactions would tend to prove or disprove fundamental ideas of the standard model.
Yes, but that's what they said about WIMPS, too, and look where that has gone so far. (Pretty much nowhere.)
Hey, if I come up with some complex theory postulating DUMPs (Dubious Universal Massive Particles), can I get funding too? After all, proving their existence would force major changes to the standard model.
This is how science works.
It's not pretty, so you don't have to like it, but your not liking it is not a valid criticism.
" no direct evidence for"
Where do you think that chain of properties comes from?
Not only are they inventing a new particle, but a new force as well ? Which is needed to explain how the new particles behave ?
If dark matter particles interacted with any of the known forces (apart from gravity), they'd interact with ordinary matter and we'd be able to see them -- in other words, they wouldn't be dark. Whatever dark mater is made of, it almost certainly involves a new and undiscovered class of particles. Most likely particles in that new class will couple to each other in new ways -- which is another way of saying they experience new forces.
Really this seems to be nothing more than an attempt to create an explanation that doesn't make predictions and is as removed from testability as possible.
Many of the less exotic ideas have been eliminated by experiment. Negative results don't make good headlines, but much progress has been made on the search for dark matter and the number of possible theories has been greatly reduced. There is a real need for new ideas of this type.
I think that dark matter is made of a yet to be discovered material called math-errorium. You'll never guess why it hasn't been discovered yet.
Or it might be time to start looking at other things entirely. Especially seeing as there has already been a considerable amount of work on finding 5th forces both attractive and repulsive When new theories start contradicting experimental data or start making statements that are untestable, at some point you have to drop back and say you have been barking up the wrong tree.
I'm not sure what you're getting at. Science follows a simple recipe: observe, predict, test. We observe that galaxies rotate in a manner that cannot be accounted for by our existing understanding of gravity and matter. A whole bunch of predictions have been made according to different ideas about how to account for galactic dynamics, from gas clouds to black holes to brown dwarfs to modified gravity to exotic particles. From time to time somebody comes up with a new idea to add to the list. Those predictions are being tested and eliminated, and so far the one that's holding up best involves exotic particles. You can be sure the more prosaic possibilities were studied first, but it turns out they have not done a good job in matching observations. But it will take time any many experiments to uncover the truth. Meanwhile we will continue to bark up all the trees that are still standing, and search for new ones to climb.
I don't think we are assuming our current theories are totally correct, otherwise we wouldn't be looking for new physics (in the form of dark matter particles) to explain what we're seeing. Signs tend to indicate though that out current mode of thinking is correct but incomplete, as opposed to being completely wrong, which is why we're not throwing out everything and starting again from scratch.
Wasn't there an article years ago about a theoretical test that only required a particle accelerator the size of Mars' orbit?
TBF, I think that would still qualify as "testable, just not with current technology".
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