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New Theory Challenges Need For Dark Matter
New submitter elsurexiste writes "An Italian Physicist came up with a strange way to explain anomalous galactic rotations without dark matter, instead relying on the gravitational effects of faraway matter. The article explains, 'Conceptually the idea makes little sense. Positioning gravitationally significant mass outside of the orbit of stars might draw them out into wider orbits, but it’s difficult to see why this would add to their orbital velocity. Drawing an object into a wider orbit should result in it taking longer to orbit the galaxy since it will have more circumference to cover. What we generally see in spiral galaxies is that the outer stars orbit the galaxy within much the same time period as more inward stars. But although the proposed mechanism seems a little implausible, what is remarkable about Carati’s claim is that the math apparently deliver galactic rotation curves that closely fit the observed values of at least four known galaxies. Indeed, the math delivers an extraordinarily close fit.' As usual, these are extraordinary claims that divert from the consensus, so keep a healthy skepticism. The paper is available at the arXiv (PDF)."
Does this explain the gravitational lensing in the Bullet Cluster?
This is the kind of theory that could have be viable prior to August 2006. When the gravity isn't pointing towards the baryonic matter, we have to postulate that there's some dark matter for the gravity to point to. Or, as Sean Carroll put it
Conventional leap of faith: this strange unseen matter exists and interacts gravitationally but somehow isn't available on Earth, cannot be created or observed or studied in a lab,
Unless supersymmetry is RP-conserving.
Electrical leap of faith: electrical processes explain the lack of mass through the electric force which is many orders of magnitude stronger than gravity and is more effective at long distances and is the only logical explanation for light-years-long jets of matter (Birkeland currents), can be observed in any laboratory with modest equipment and is known to scale both up and down, and through processes not yet understood there is enough charge separation in the Universe to provide the potential difference to cause these circuits to flow.
If you're willing to believe that far off galaxies have ridiculous amount of charge separation (something we have no theories or experimental evidence for), then believing that there are weakly interacting massive particles or other forms of dark matter can't be a stretch. Electromagnetism is strong (relatively), there would have to be something really trying to hard to convince the different charges to keep apart
I wonder how long it will be before science is forced to throw out dark matter and embrace electrical effects. Ten years? Twenty?
It's not a matter of time, it's a matter of evidence. If you can come up with a self-consistent theory that explains these electrical effects and have predictable effects that can be measured then you can have your moment in the sun.
-Bucky
A religious rant, condemning other theories as inadequate, antiquated, and conforming to orthodoxy. On the internet too. Wow, who would have anticipated that?
To be fair, using mathematical models on stuff we can see and measure seems a reasonable idea as opposed to inventing an invisible, incorporeal, magical material that we have no direct evidence even exists in order to compensate for our lack of understanding in how the Universe moves.
I just want to say- what little I do know, I've always disliked dark-matter. It always seemed to be a case of "we can't explain 'x' - so let's claim there is dark-matter and that will make our hypothesis match what we observe."
But you should realize that this technique has been used throughout the entire history of modern science, and its track record is actually quite good.
Back in the late 1700s, after the discovery of the planet Uranus, astronomers made careful calculations of its orbital elements and published a table the position of the planet in the sky over the years (and decades). As the years (and decades) wore on, they discovered a curious thing: the actual position of the planet was beginning to diverge from what had been predicted.
At this point, there were a few different explanations:
1) Perhaps the initial orbital elements were incorrect.
2) Perhaps our fundamental laws of gravity and motion were incorrect.
3) Perhaps there was a massive, as-yet-undetected eighth planet whose gravity was influencing the orbit of Uranus.
Most astronomers fell into the third camp; after all, the observations of Uranus's orbit had been made with considerable precision (for the time) and there was little reason to believe that the fundamental laws of physics would start to break down as you move further away from the sun. And so they made their calculations and narrowed down the location of this hypothetical planet to a fairly small window in the sky. After that, it was just a matter of pointing a telescope there and looking.
This is the story of the discovery of the planet Neptune.
Astronomers did not find this planet by accident. It was not discovered by a kid in the backyard with a streak of cosmic good luck. (In fact, many observers from antiquity had seen it, but had not realized what they were looking at.) They found it because they knew it had to be there.
Now, you might think that this comparison is a bit of a stretch. But it's just one example; there are countless more. Back in 1930, Wolfgang Pauli was studying beta decay in atomic nuclei. He realized that the process, as he was seeing it, could not possibly be happening unless there were (again, hypothetical) particles being emitted as a consequence. If there were not, then all sorts of fundamental principles of physics were being violated (e.g., conservation of matter / angular momentum / etc.)
This particle, eventually named the "neutrino", remained hypothetical and undetected for more than a quarter of a century until it was finally detected -- in 1956.
I could go on, but the point is that postulating the existence of something hypothetical in order to explain deviations between theory and observed results is part of the best traditions of natural science. It's not hand-waving or charlatanism. And it works more often than most people might think.
We're going down, in a spiral to the ground
DISCLAIMER: I am not a astrophysic, and I have the good sense to not to claim that the new theory looks like better (fits observations better) than dark matter. The scientific process will eventually sort it out (and not through an /. poll). This post is not about the theory but about the posts on it.
When Wegener postulated its theory, even if the underlying details were not fully understood, it was a scientific one because it answered to observation (size of continents, identical fossils found at different continents, etc.).
Fortunately, there was no internet then, because there would be a deluge of posts by uninformed people who didn't knew shit of what they were talking about, but felt that theory too "radical" and that they had to restore order (go read the GGP talking about "totally divorce the mathematics from natural philosophy").
The most funny things about those guys is that they would look at the abstract of a full scientific study and counter it with and abstract... "similar fossils? they have been spread by African swallows. Hey, that solves it, I am so sure that I won't ever check if this can be possible."
Nowadays, we have some amateurs who take several years of observations, heavy mathematical work and just threw out of their asses "I'd look at friction of intestellar gasses around the ejection plumes from black holes". Where is your data? Your correlation of the expected results with observations? Your predictions and/or experiments?If you have some of it, don't send it to me, publish the paper to help science, please.
Don't get my wrong, I am not annoyed by it. It could be annoying if those people were wasting someones time for this, but no scientific is going to come to /. searching for theories, so it is mostly harmless entertainment that brings a smile to my face :-)
The funny thing is that those nutjobs always leer in the same direction, opposing the "unnatural" posibilities. Are they afraid that the world is becoming too complicated? I feel there are too many camouflaged ludites out there.
And, finally, my goodbye present.
Why can't
As a physicist: You are Idiot and uneducated in the history of physics. Lets take some instances of when people invented something "to make the math work" (uhm yes, thats what physicists are trying to do in the end.....)
a) Ether Wind. They made is up "to make the math work" as an alternative to "change the underlying euquations".... And the winner was "change the underlying equations". Without specific predictions from the Ether WInd Hyphothesis one could not have constructed the Michelson-Moreley Experiement
b) Neutrinos. Long predicted, because some momentum was missing. At that moment the neutrino was "dark matter". As we all know, Neutrinos exist. Is everybody would have believe that Neutrinos are utter bullshit because they "just ake the math work" nobody would have developed a theory for detecting them.