New Theory Challenges Need For Dark Matter 302
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)."
Re:"Intelligent" gravity force (Score:5, Informative)
It's called Intelligent falling. [wikipedia.org]
There is other evidence. (Score:5, Informative)
I don't understand why this theory is "implausible" and why the article is so dismissive of it. Dark Matter was created for the sole purpose of explaining the orbital momentum of stars. There is NO other evidence for it.
There is lot of other evidence for non-baryonic Dark Matter:
* Lack of MACHO gravitational lensing
* Existence of unexpected gravitational lensing in Bullet Cluster.
* CMBR measurements
* and more.
It isn't hard to modify equations to match the galaxy rotation curves, and if that was the only evidence for dark matter it wouldn't be so strongly favored.
Re:what's going on in italy lately? (Score:5, Informative)
Just in case anyone isn't aware, the parent post is a rant about the "electric universe" "theory". Basically, it's pseudoscientific quackery. Not because of scientific snobbery, or some sort of conspiracy against the theory, but because most of it is quite obviously bunk. It's basically just a form of monomania.
Re:"Intelligent" gravity force (Score:4, Informative)
You jest, but
http://en.wikipedia.org/wiki/Naval_Battle_of_Guadalcanal#First_Naval_Battle_of_Guadalcanal.2C_November_13 [wikipedia.org]
Re:what's going on in italy lately? (Score:0, Informative)
Remind me how the Electric Universe theory explains nucleosynthesis? If stars are actually just big balls of iron and nuclear fusion isn't powering them, where did the iron, and all of the other elements come from? Traditional cosmology explains it pretty well, and decades of observations of stars at all stages of development supports those explanations very well. How does the Electric Universe fit with all the existing evidence?
Eh what? Did you ever actually study this theory before deciding to comment on it? Of course not.
Two places to start: Holoscience [holoscience.com] and Thunderbolts. [thunderbolts.info]
Hint: they never claim stars are balls of iron. You deserve to feel like a moron for criticising something you do not understand. I doubt you have the objectivity and humility to admit fault here, though. You will probably take the coward's way out and assume I must be insulting you for no reason. Moving on...
They claim they are balls of ionized plasma (i.e. gas-like, not solid-like). Also, sufficiently powerful arc discharges can transmute elements. Also, EU theory doesn't say no fusion happens on a star. It says the star isn't powered by fusion. It would be more like the way we do fusion here on earth, by supplying energy (via laser beams typically) that causes the material to fuse. Just like here on earth, it isn't self-sustaining. It is powered by the energy of the sustained electric discharge.
This seems to be all that the EU haters bring to the table: demagoguery, misrepresentation, and straw men. Pathetic, even if unintended. It suggests you just heard something repeated a few times and ran with it and made no effort to validate what you believe. It's called drinking the kool-aid when people do this in the political arena.
If the above sounds harsh it's because I get tired of how misinformed and thick-headed many of you are. You are armchair critics who make no active effort to learn about something before deciding it must be total bullshit. Anyway, if you want to see the actual EU position on the Sun, please read this [holoscience.com].
Re:The Bullet Cluster (Score:5, Informative)
You have to distinguish between a theory, and a model based on a theory. "Dark matter" is a hypothesis/theory... this paper on the other hand isn't proposing anything new, it's just a different way of modelling galaxies that accounts for "far-field" interactions. The theory here is just general relativity, and the author claims that when you account for the relativistic effects of distant matter in your calculations, the unexplainable rotation curves that originally justified the hunt for 'dark matter' are now explainable.
Now this doesn't prima facie explain things like the Bullet Cluster; you'd have to redo the bullet cluster calculations accounting for these long distance effects. And of course, if it were simply the case that 'we did the math wrong and assumed something was insignificant when it isn't,' then it would be an enormous amount of egg-on-face for a lot of physicists and research groups. But personally I find it likely that the math was wrong AND there are still-not-understood dark matter/quantum gravity effects at work.
Re:No (Score:4, Informative)
His model is less accurate than that which is predicted by dark matter. The fact that it does align with several known observations makes it at least worth consideration, but realistically, there are a dozen or more theories about this, most of which are a little crackpot.
To entertain alternatives because the consensus theory is still in doubt is healthy, but the consensus still represents to most scientists, the most plausible and will continue to drive current research efforts until a new model is proven fairly conclusively, to be more accurate.
This is how science works and it is not broken. I can clearly tell you are not a scientist and you also have issues with other science that may or may not have plausible alternative models, which may or may not match current observations and experimental results with more or less success, but which still haven't caught on because of gaps in their explanations of various observed phenomena.
The scientific method isn't perfect, but it serves us well in general and it is worthwhile to stick with it in order to attempt to explain our surroundings. Are you implying otherwise?
Re:what's going on in italy lately? (Score:5, Informative)
They'll do anything, absolutely anything, invent any figment, totally divorce the mathematics from natural philosophy, propose strange exotic forms of matter never observed, and claim their existence is "proven" because they have a favorite explanation among multiple explanations not requiring strange exotic forms of matter.
The mysterious "Them"! A shadowy organization, nefarious and wicked.
They will do all of this, and more, to avoid admitting that "million degree gas" is conductive plasma and there is electricity in space and its attractive force is linear instead of following an inverse-square law, totally eliminating the need for any dark matter.
So Coulomb's Law is completely wrong just because PLASMA and ELECTRICITY IN SPAAAAAAAAAAACE!!! ? Why does nobody ever observe a linear attractive force for electric charge in the lab, under any conditions (including evacuated chambers and plasmas)?
And how does an incoherent shambling mess of a crackpot theory (the entire family of Electric/Plasma Universe wingnuttery) believed only by ignoramuses like yourself who don't even understand that like charges repel and opposite charges attract, a theory which has been disproven a thousand times over by real scientists doing real science, a theory which never gained any traction at all because it doesn't match how the universe observably works, solve anything at all?
Both require some kind of leap of faith. 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, and is proposed to exist merely to fix a broken theory that never predicted its existence but can't get the expected results without it (Karl Popper spins in his grave...).
Nobody requires that you take a leap of faith and "believe" in dark matter. It's just the best explanation we've got right now, and last I checked, scientists are actively searching for both confirmation and disconfirmation of dark matter. If it were a faith industry, nobody would be doing either and that would be that.
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
Trying to use the electric force to explain the observations which led to the proposal of dark matter is flatly stupid. Remember what I said just above about you not understanding that the electric force is only attractive for opposite charge? If you don't accept that, you are going against every observation of the electric force, ever. If you do accept that, then you've just disproven the electric universe theory, because the observed discrepancies from Newton's Law at cosmological scales are evidence of a consistently attractive force, like gravitation. If stars and planets and clusters and so forth were actually far enough from electrically neutral for the electric force to be a significant factor in their interactions with one another, you could never find a set of 3 objects which all attracted one another. Such objects are routinely found, therefore the electric universe theory is bunk.
So yeah, the EU theory requires a leap of faith: the kind of leap which requires you to ignore solid evidence which absolutely disconfirms the theory.
and is the only logical explanation for light-years-long jets of matter (Birkeland currents),
Calling LY-long jets of matter Birkeland currents is a perfect example of how EU true believers try to claim random phenomena as their own without rigorously linking them to EU theories. Birkeland's predictions related to the aurorae on Earth, not cosmological objects.
can be observed in any laboratory with modest equipment and is known to scale both up and down, and
Re:"Solves" one issue of dark matter only (Score:4, Informative)
Supersymmetry is problematic as the simplest forms are now falsified by the LHC. You have to assume a more complex form - which is valid, but I have seen no evidence that the CDM theory has been re-examined to see what the impact of the LHC observations is.
The Bullet cluster obviously needs explaining, but I saw nothing on the Wikipedia page that indicated why Dark Matter was needed as a part of that explanation. There is clearly a drag effect of some sort, but there are plenty of potential causes of drag. Which ones are viable depend on the precise angle of each galaxy at the time of collision and the probability based on known classes of stellar object of various types of high-pressure event occurring. I would imagine that such work has been done but Wikipedia showed none that I could see.
CMB is a problem because certain fluctuations could potentially be the result of specific multiverse theories being correct. Due to the lack of ability to see multiverses, CMB alone is not a valuable indicator because you cannot test the different hypotheses. There's no means of distinguishing a valid model from an invalid one. I am not saying CMB isn't a demonstration of dark matter, merely that it is only suggestive of being a demonstration of dark matter. Until such time that enough observations have dark matter as the only common suggested solution to all of them, the best you can say is that CMB allows for the possibility of dark matter.
Re:No (Score:3, Informative)
"His model is less accurate than that which is predicted by dark matter."
Dark matter doesn't predict anything. Dark matter is a thing hypothesized to exist that might explain our observations.
Re:"Intelligent" gravity force (Score:3, Informative)
I'm going to nitpick your nitpicking, because there's some really objectionable stuff in it.
Oh, come come -- this is a story about how many of us scientists don't just believe in invisible tea-sets in space (Russell's accusation of religion), we believe there's more invisible tea-sets (dark matter) than visible matter!
That's ridiculous. Russell's tea-set analogy was to illustrate how a person who believes in religion does so without any positive evidence or reasoning. The hypothetical believer in space teapots believes in them in spite of the fact that not only have none been found wandering about the solar system, there's no reason to expect them to be present in the first place.
Dark matter does not fit that criticism in any way. It's an attempt to explain an interesting conundrum:
1. We think we know a lot of physics. Relativity and quantum theory aren't unified, but they each work very well in their respective domains.
2. We've been finding that there isn't enough visible mass (where by visible I mean "in the electromagnetic spectrum", not just the human range of visibility) to account for the observed gravitational interactions between many cosmological objects.
Dark matter is one possible answer for this problem. There might be matter which is hard or impossible to observe via EM spectrum emissions, so the only way we can notice it at cosmological distances is its gravitational influence on other matter. This is in no way analogous to Russell's teapot, because it is a hypothetical explanation for an observed fact, not a context-free irrational belief in a ridiculous notion.
And bet millions of dollars of research funding on that belief. While the chap who's saying "maybe there's no dark matter" is fighting an uphill battle.
This is nonsense, because the "maybe there's no dark matter" side has in fact been able to get funding. So far the "there's probably dark matter" side seems to be winning. That doesn't mean there's a religious belief in DM, just that it seems to fit the observable facts reasonably well, while the alternate theories proposed to date (modifications of existing physics, such as MOND) have generally failed to pass basic smell tests (such as whether they can reproduce well known experimentally verifiable phenomena).
Re:what's going on in italy lately? (Score:4, Informative)
That's only ONE of the problems dark matter addresses. The others are conveniently not mentioned by dark matter alternatives, because the alternatives do not address them well.
Re:The "dark" in "dark matter" isn't just "dim." (Score:4, Informative)
"It is also what you would see if the majority of the dark matter is MACHOs"
No, it's not. In the bullet cluster all the regular, baryonic matter we can see (which is not just stars but also gas and dust) shows a drag effect. By looking at gravitational lensing we know that the majority of the matter actually does NOT show this drag effect. The majority of the matter in the cluster is behaving as if it doesn't interact with anything, except through gravity.
MACHOs definitely do interact through forces other than gravity, and behave just like baryonic matter (because they ARE baryonic matter). You're sitting on one, after all.
No to the "No" (Score:4, Informative)
Hopefully this helps you understand where the idea of 'dark matter' came from. (Hint: arses don't seem to be an element.)