CERN Physicist Says Dark Matter May Be an Illusion 379
anonymousNR writes "A CERN physicist has a new theory explaining the rotational curves of galaxies. 'The key message of my paper is that dark matter may not exist and that phenomena attributed to dark matter may be explained by the gravitational polarization of the quantum vacuum,' Hajdukovic told PhysOrg.com. 'The future experiments and observations will reveal if my results are only (surprising) numerical coincidences or an embryo of a new scientific revolution.' Given the many theories around explaining various observations in recent times, there seems to be a breakthrough on its way in our understanding of the cosmos."
no dark matter... (Score:5, Insightful)
I hope so. Dark matter is the ugliest kludge to the standard model ever.
It's worse than the Plus upgrade for Windows 98.
Yay for phlogiston and aether (Score:4, Insightful)
Yay for phlogiston [wikipedia.org] and aether [wikipedia.org]. Dark matter might end up on the list of ideas that physcists turned to in order to explain things that had other explanations. La plus ca change...
Re:no dark matter... (Score:2, Insightful)
Re:Yay for phlogiston and aether (Score:5, Insightful)
Hopefully. Dark matter is a very inelegant solution to observations that don't agree with theory. Even so, working out what properties it must have, should it exist, is a useful exercise because it clarifies the problem more thoroughly.
There seems to be a common misconception that incorrect theories were stupid ideas from the get-go. That's really not the case, until new evidence or new ideas come up the incorrect theories are every bit as valid as the ones that may turn out to be correct and the differences between the various competing theories may point the way to interesting new experiments.
This new theory is probably wrong, but it's founded on an assumption that, while not currently accepted as true, is experimentally verifiable. That's the assumption that anti-matter and matter have gravitation fields of opposite sign. An experiment to determined the truth of that would be very interesting.
Re:Can't see the quantum vacuum for the dark matte (Score:5, Insightful)
What really surprises me is, despite this, so many physicists have jumped on the bandwagon.
This is because it is the simplest theory which fits available data. There are simpler theories, but they do not fit available data, and thus are of little value.
Average Slashdotters have been more skeptical of they dark matter theory than physicists, from what I've seen.
This is because average Slashdotters do not have even the beginnings of a clue about astrophysics, but think they are expert at every subject they ever heard mentioned on the internet.
Re:no dark matter... (Score:3, Insightful)
Nothing New (Score:2, Insightful)
From TFP: "Let us end by pointing that the rotational curves of galaxies are not the only phenomenon
which is currently explained by Dark Matter. For instance, CMB data are apparently in favor of
the presence of dark matter as a key for understanding of density fluctuations and the structure
formation in the Universe (see review of Einasto, 2010). While our Letter gives indices that the
gravitational vacuum polarization could be an alternative to dark matter in the explanation of the
galactic rotational curves, a tremendous work would be needed, to reveal if the other phenomena
could be alternatively explained by the vacuum polarization."
In other words, it's just another MOND theory, of which there have been many over the years. Wake me when MOND proponents write a theory that explains *all* the evidence for dark matter, CMB, nucleosynthesis, rotation curves, etc., not the particular phenomena they've cherry-picked. Until then, dark matter, whether that's WIMPs, MACHOs or axions, is the only explanation that fits all the evidence thusfar.
Re:no dark matter... (Score:4, Insightful)
Scientists SHOULD BE convinced otherwise when evidence becomes available, and 8/10 times base their assumptions on factual information. Religions do both to a much lesser extent.
Fixed.
There are plenty of scientists out there with pet theories that they will fight for to the bitter end.
Re:if you can't see it, it doesn't exist... (Score:4, Insightful)
You can detect dark matter. If it exists, we have already indirectly detected it. We have not yet directly detected it, but that is not because it not possible to do so, just that we have not succeeded yet. We are currently trying to do so.
Using similar methods, there was a time when you could "detect" epicycles, too. Like dark matter they were a theoretical fudge factor designed to prevent a cherished theory from falling apart due to its lack of successful predictions and explanatory power. In the case of epicycles, the cherished theory was geocentrism. You would have been ridiculed extensively (and quite possibly be in danger of the Inquisition) for questioning it, not because your own theory wasn't viable or couldn't also explain the observed results but because "everybody knew" how "well-established it is" that the earth is the center of the solar system...
If they teach scientists about the history of these things as part of their normal training, they don't do a very good job. At all.
Re:no dark matter... (Score:2, Insightful)
Re:no dark matter... (Score:1, Insightful)
Re:Yay for phlogiston and aether (Score:4, Insightful)
Exactly. It was the development of the theory of the aether that led to many of the experiments surrounding the properties of light that allowed the theory of relativity to be developed. For instance, we knew if aether existed it would create a "wind" that would slow light in some directions as the earth moved. The experiment to test that wind helped found the theory of relativity (although, interestingly enough, Einstein supposedly hadn't heard of the experiment when he postulated the constancy of the speed of light.)
Aether was by no means a stupid theory, but it required a number of new properties previously unseen in material bodies, and it was theorized solely as a kludge to explain the motion of light through a vacuum. The analogy with dark matter is quite strong. Dark matter, too, has never been observed, and possesses properties of matter previous unseen or indeed thought impossible, and exists solely to bridge a gap between our model of how things should behave, and how things actually behave. This does not bode well for it. However, the experiment to test for its existence is quite likely to lead to something interesting, even if we have no idea what.
Re:If you can't handle the concept of dark matter (Score:2, Insightful)
Well, there's also a lot of:
You're assuming that 90% of the universe is invisible on the basis of *what* evidence? I'd like a bit of better evidence, please, before I swallow something like that.
It's something that *could* be true, but the evidence is pretty thin for the size of the hypothesis. Maybe it's the best we can do, and maybe it isn't. For a while longer I'm going to presume that eventually we'll come up with either a better answer, or more convincing evidence. The current evidence is proof of something, but it's not clear that what it's a proof of is the current best theory. Maybe it would be better to suspend premature certainty.
N.B.: I, and many others, aren't active physicists, so we don't NEED to decide what things mean right now. It's ok for us to suspend belief, and not be certain which theory is correct. Start making predictions that directly affect us, and this will change. I believe that the previous sentence also applies to most active physicists. And even to many cosmologists.
But I admit to being skeptical about dark matter and dark energy. They're explaining something, but I doubt that they are the correct explanation. What I see them as being is something that's good enough to allow the equations to balance right now. But given the paucity of evidence, I'm not convinced that they're the right shape for an explanation.
It's sort of strange. I'm rather attached to the multi-world interpretation of quantum theory, and that also has no effect on what I see or do. It could be Copenhagen and it wouldn't make any practical difference to me. But I dislike the Copenhagen interpretation. And there is *NO* evidence to allow one to choose between them.
Re:no dark matter... (Score:5, Insightful)
Do you have a hard time stomaching neutrinos too? When they were first proposed they could not be detected. Still they solved the very real problem of explaining the beta-decay spectrum.
Re:no dark matter... (Score:5, Insightful)
I mean, why do you think we call it "dark matter"? That is literally all we know about it - we know it has weak electromagnetic interactions (i.e, it's dark), but strong gravitational interactions (i.e, it's matter).
The thing you really seem to object to is that scientists will say "Hell, I don't know - but I'll put a name on it, and start narrowing down what it can and cannot be".
I mean, what do you expect? That we'll admit "hell, I don't know" and just stop? And just give up right there? Hell no - saying "I don't know" is the first step of doing science, not the last step!
Re:no dark matter... (Score:5, Insightful)
No one would have a problem with the notion of such a God. It's when the God of all space and time starts setting bushes on fire and demanding that people vote Republican that people start to call bullshit.
Re:no dark matter... (Score:2, Insightful)
So, one untested theory turning out to be true means all untested theories are true?
Bad science (Score:3, Insightful)
Go to a fundamentalist church group some time and tell me you really think they are more capable of understanding when they are wrong.
Would you want someone to base their opinion of Americans based on trip to a US insane asylum? If not then why would you think a visit to a fundamentalist church would be a good way to judge a religion as a whole? Both are only fractions of their respective societies and both are filled with people who have a tenuous grasp on reality. It is bad science to use a biased sample like that on which to base your judgements.
Re:no dark matter... (Score:5, Insightful)
No, but a new, untested theory doesn't automatically disprove an older, also untested theory just because it sounds more plausible or because you like it.
Re:no dark matter... (Score:5, Insightful)
Agreed. I have always had a hard time stomaching the theory that dark matter and dark energy exist. It seems far too much like aether, i.e. something made up to fill a gap in knowledge without much evidence backing it up.
The problem is that the universe is pretty good at ignoring people's bowel movements, a lot of things are completely unintuitive. If I look at a wall it looks damn solid to me, my gut feeling would be that radio and wireless can't possibly work. And if you told me there are particles that'll pass through thousands of miles of earth and stone and lava without even caring that it's there, I'd say you were ready for a room with padded walls if only it wasn't true. In short, past experience has shown us that this is an area where the universe has a habit of not acting the way people expect.
That said, we do know our understanding of gravity is incomplete at the quantum level, we probably will get a better understanding of it as we go along. But the unexplained gravitational effect seems variable, lumped together just like real matter and not always directly in proportion to it. I could accept that we might have had to adjust gravity by some sort of factor but it seems a bit too erratic to be just a formula adjustment. I at least am pretty confident that we've not found all the particles yet and that this will be at least part of the explanation.