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New Theory Challenges Need For Dark Matter

Soulskill posted more than 2 years ago | from the propagating-through-the-ether dept.

Space 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)."

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302 comments

Happy Holidays from the Golden Girls! (-1)

Anonymous Coward | more than 2 years ago | (#38271450)

Thank you for being a friend
Traveled down the road and back again
Your heart is true, you're a pal and a cosmonaut.

And if you threw a party
Invited everyone you ever knew
You would see the biggest gift would be from me
And the card attached would say, thank you for being a friend.

No (5, Funny)

Anonymous Coward | more than 2 years ago | (#38271484)

I'm sorry, but "gravitational effects" won't sell popsci books. For the sake of our royalties, let's stick to dark matter.

Re:No (4, Funny)

vandon (233276) | more than 2 years ago | (#38271510)

Yes, I agree. Dark gravity deniers should be kicked out of their profession. Once a consensus is reached, it is recognized as FACT!

Re:No (1)

Anonymous Coward | more than 2 years ago | (#38272560)

Consensual reality? What the fuck bro?

Re:No (1)

Anonymous Coward | more than 2 years ago | (#38272628)

WHAT SENATURS DID U BY?!?!?! wer owned by teh croprorashuns!!

Oh... were we not doing one of those? My apologies. Do carry on.

what's going on in italy lately? (4, Interesting)

Sebastopol (189276) | more than 2 years ago | (#38271486)

faster than light neutrino measurements?

revolutionary-yet-pseudo-sciency sources of energy?

and now dark matter challenges?

coincidence or what?

Also (5, Funny)

MrEricSir (398214) | more than 2 years ago | (#38271542)

Also there was that Galileo guy too.

(Must be all the espresso they're always drinking.)

Re:Also (2, Funny)

Anonymous Coward | more than 2 years ago | (#38271704)

(Must be all the espresso they're always drinking.)

Hmmm... your espresso theory might explain some of the software made in the Seattle area in more recent years.

recent years? (0)

Anonymous Coward | more than 2 years ago | (#38271984)

When has the Seattle area actually produced good software?

(Yes there are some very good engineers there, but they're just the extreme of the bell curve and somehow manage to find work.)

Re:recent years? (0)

Anonymous Coward | more than 2 years ago | (#38272164)

Are you implying that Seattle espresso is not as good as Italian espresso??

Re:recent years? (2, Insightful)

Anonymous Coward | more than 2 years ago | (#38272690)

Yes. ANY Coffee in America is overroasted dog shit

Re:recent years? (0, Offtopic)

Anonymous Coward | more than 2 years ago | (#38272772)

coffee makes me poop alot

Re:what's going on in italy lately? (4, Funny)

marcello_dl (667940) | more than 2 years ago | (#38271680)

Maybe, with chronically insufficient funding, researchers work better. It'll be known as the Paradox Berlusconii.

Re:what's going on in italy lately? (2, Interesting)

Anonymous Coward | more than 2 years ago | (#38271690)

faster than light neutrino measurements?

revolutionary-yet-pseudo-sciency sources of energy?

and now dark matter challenges?

coincidence or what?

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. 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.

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...). 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.

Or they can keep getting surprised, shocked, and amazed when they keep discovering celestial objects not predicted by their theories.

I wonder how long it will be before science is forced to throw out dark matter and embrace electrical effects. Ten years? Twenty? It definitely won't be the first time an idea was long ridiculed before the consensus collapsed under its own weight and was later found to be valid and embraced. They call it a paradigm shift. It only happens this way because of a lot of stubborn bastards who chase pet theories and grant money and don't teach new students about alternative theories. Halton Arp's compilation of galaxies with highly redshifted quasars _in front of them_ and _physically connected to them_ alone should have made them reconsider, but instead he is ignored because he doesn't fit the orthodoxy. I thought science was supposed to be different from religions with their orthodoxies and heretics and apostates?

Re:what's going on in italy lately? (3, Funny)

gstrickler (920733) | more than 2 years ago | (#38271846)

A religious rant, condemning other theories as inadequate, antiquated, and conforming to orthodoxy. On the internet too. Wow, who would have anticipated that?

Re:what's going on in italy lately? (2, Interesting)

Anonymous Coward | more than 2 years ago | (#38272106)

A religious rant, condemning other theories as inadequate, antiquated, and conforming to orthodoxy. On the internet too. Wow, who would have anticipated that?

... a rant that explains why the writer believes one theory to be better than the prevailing one by reviewing the merits of both.

I know it's trendy to just look down your nose and condemn something without actually explaining what's wrong with it and why you disagree, and certainly it's trendy to avoid setting a better example by taking a position yourself that doesn't have the qualities you're complaining about... but don't you feel like a bitch when you do things this way? No insult intended, I mean "bitch" as in "bitching" as in completely non-constructive whining that doesn't fix or challenge or change anything.

If you think the Electric Universe theory is invalid, or that the conventional theories with their ad-hoc explanations and retroactive revisements to deal with failed predictions are better, or that the scientific censorship encountered by Arp and others who were denied telescope time and denied publishment in peer-reviewed journals (that certainly could find any flaws in their theories consistent with the entire purpose of peer review) is the right way to handle dissent in a supposedly scientific establishment ... feel free to explain why. Take your own position. Show why the previous one is lacking.

Be at least slightly respectable by bringing something to the table. Try it on for size.

Re:what's going on in italy lately? (2)

tragedy (27079) | more than 2 years ago | (#38272728)

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?

Re:what's going on in italy lately? (0, Informative)

Anonymous Coward | more than 2 years ago | (#38272934)

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:what's going on in italy lately? (1)

Anonymous Coward | more than 2 years ago | (#38272736)

The Electric Universe theory has been debunked over and over and over. It's as real as orgone energy or homeopathic medicine or Scientology -- meaning completely quackery with no foundation in science or reality.

All crackpot theories have the same defense: that all of academia is making a group effort to discredit the theory because accepting it goes against too many well-established norms. And you said it yourself, everybody is teaching the "wrong" theories and ignoring the Electric Universe concept.

Also I'm pretty sure you are trolling, but can't say for sure.

Re:what's going on in italy lately? (5, Insightful)

rainmouse (1784278) | more than 2 years ago | (#38272620)

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.

Re:what's going on in italy lately? (1)

DM9290 (797337) | more than 2 years ago | (#38272700)

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.

So reasonable in fact, it's a wonder no one has done it before, or maybe they have and they are keeping it a secret! .... it must be a government conspiracy!

Re:what's going on in italy lately? (2)

gstrickler (920733) | more than 2 years ago | (#38272894)

You mean Mathematical models like the theory of gravity? Yup, sounds pretty reasonable.

Re:what's going on in italy lately? (5, Insightful)

bucky0 (229117) | more than 2 years ago | (#38272190)

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.

Re:what's going on in italy lately? (4, Interesting)

HiThere (15173) | more than 2 years ago | (#38272784)

Somehow this argument sounds like the argument for continental drift before plate tectonics.

OTOH, I note that the another comment denies that the mathematical fit is all that good. This isn't really convincing, as I heard similar denials of continental drift before a plausible mechanism was discovered.

Still, if that it so you can expect it to continue to be rejected in a way that seems to you unreasonable UNTIL you come up with a plausible mechanism (for charge separation?). Personally I'd look at friction of intestellar gasses around the ejection plumes from black holes. Friction is well known for causing charge separation between, e.g., fur and glass. Now you've got to come up with your analogs to fur and glass...or come up with some other mechanism. But until you provide a plausible mechanism, this theory will be rejected without reasonable examination. Expect it.

Show us the math (4, Interesting)

Fujisawa Sensei (207127) | more than 2 years ago | (#38272462)

Just show the math and how it correctly models modern astronomical data.

I'll give you a hint, it doesn't even come close.

Re:what's going on in italy lately? (4, Informative)

tragedy (27079) | more than 2 years ago | (#38272596)

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:what's going on in italy lately? (3, Funny)

bill_mcgonigle (4333) | more than 2 years ago | (#38272734)

coincidence or what?

Don't forget - they also have geologists on trial for failing to predict the earthquake a few years ago. The Universe is merely seeking equilibrium.

"Intelligent" gravity force (1, Funny)

gapagos (1264716) | more than 2 years ago | (#38271504)

I can't wait for some religious nutbar to claim that an "intelligent" gravity theory should be joined to any other existing theory in scientific discussion.

Re:"Intelligent" gravity force (5, Funny)

canajin56 (660655) | more than 2 years ago | (#38271594)

The name "gravity" is prejudicial as it presupposes a connection between the alleged force and weight! "Intelligent Falling" is the preferred term.

Re:"Intelligent" gravity force (5, Funny)

Warwick Allison (209388) | more than 2 years ago | (#38272438)

Indeed, stupid scientists made a big complicated theory about forces proportional to masses and then after doing experiments and finding that things fall the same regardless of mass, they cover up their error by adding even more factors!

Occam's Razor requires us to believe that stuff all falls at the same rate because God decided that was the best rate.

Why this rate? When God created the world, He made the rate of fall exactly enough that we could walk on two legs, while all Lower creatures cannot because the Falling Speed is not tuned for them. If Falling was even slightly slower or faster, your feet would hit the ground out-of-step and would not be able to walk - co-incidence? No, proof that God made the world for Man.

Re:"Intelligent" gravity force (4, Funny)

MiniMike (234881) | more than 2 years ago | (#38272950)

When God created the world, He made the rate of fall exactly enough that we could walk on two legs, while all Lower creatures cannot because the Falling Speed is not tuned for them. If Falling was even slightly slower or faster, your feet would hit the ground out-of-step and would not be able to walk - co-incidence? No, proof that God made the world for Man.

Finally the long awaited proof that Ostriches are the work of the devil!

Re:"Intelligent" gravity force (0)

Anonymous Coward | more than 2 years ago | (#38271622)

I don't hold that against you in any way - intelligent gravity pulled your keys down to make you write the objection to it.

Re:"Intelligent" gravity force (5, Informative)

Anonymous Coward | more than 2 years ago | (#38271644)

It's called Intelligent falling. [wikipedia.org]

Re:"Intelligent" gravity force (1)

gapagos (1264716) | more than 2 years ago | (#38271960)

You, sir, beat me to it. I applaud you.
^ Please mod parent up +1 informative. :-)

Re:"Intelligent" gravity force (0)

Anonymous Coward | more than 2 years ago | (#38272590)

Yeah, no one has ever heard that one before.

Re:"Intelligent" gravity force (4, Funny)

almitydave (2452422) | more than 2 years ago | (#38271720)

Well, THIS religious nutbar subscribes to the theory that gravity is really just the love felt between particles: just as absence makes the heart grow fonder, distance increases this attractive force, resulting in increased orbital velocities of stars.

Love makes the galaxy go 'round.

Re:"Intelligent" gravity force (0)

msauve (701917) | more than 2 years ago | (#38271748)

"I can't wait for some religious nutbar to claim that an "intelligent" gravity theory should be joined to any other existing theory in scientific discussion."

"Intelligent gravity" would be an oxymoron, since it's really comedy.

Re:"Intelligent" gravity force (1)

ShavedOrangutan (1930630) | more than 2 years ago | (#38271788)

Your troll is about as insightful and useful as a First Post! or a Goatse.

Re:"Intelligent" gravity force (0, Troll)

mcgrew (92797) | more than 2 years ago | (#38272198)

Odd how the fanatical, radical athiests get away with trolling so easily, and sometimes get modded up. Athiesm takes as much of a leap of faith as belief in a diety or dieties. More if you've actually experienced a diety. It's sad how so many athiests think religion is anti-science, and how they somehow think that you can have science or religion but not both, when over half of scientists are in fact religious.

I wish everyone would stop the damned trolling. It annoys me and detracts from slashdot. This thread is no place for a religious discussion. And if they don't believe in a diety why do they even mention one?

Re:"Intelligent" gravity force (0)

ShavedOrangutan (1930630) | more than 2 years ago | (#38272474)

If someone told me they pray to the tooth fairy, I'd smile and hope that it brings them peace and happiness. There are a lot of atheists here that could use a deity to teach them not to be an asshole.

Re:"Intelligent" gravity force (0)

Anonymous Coward | more than 2 years ago | (#38271814)

I can't wait for some anti-religious nutbar to claim that religious nutbars are going to claim that an "intelligent" gravity theory should be joined to any other existing theory in scientific discussion.
 
Oh, Wait!
 
Seriously, is that the most you can add to the conversation is a cheap shot at religion? I will agree that if such a claim is made it should be picked apart but can we just hold off the hostilities until it happens? For once?

Re:"Intelligent" gravity force (4, Interesting)

Daniel Dvorkin (106857) | more than 2 years ago | (#38272032)

Seriously, is that the most you can add to the conversation is a cheap shot at religion?

It wasn't a shot at religion, it was a shot at religious fanaticism. There's a difference, and pretending otherwise is disingenuous at best.

I will agree that if such a claim is made it should be picked apart but can we just hold off the hostilities until it happens? For once?

Hostilities were opened a long time ago. Your objection makes as much sense as saying to the captain of a US Navy ship, "I agree that if that Japanese ship over there shoots at us, we should blow them out of the water, but can we just hold off the hostilities until in happens?" in 1943.

Re:"Intelligent" gravity force (4, Insightful)

jensend (71114) | more than 2 years ago | (#38272246)

Translation: "I'm not bright enough to think about orbital dynamics, so I'll just try to start an offtopic religion-bashing troll thread instead."

Re:"Intelligent" gravity force (0)

Mikkeles (698461) | more than 2 years ago | (#38272786)

I can't wait for some religious nutbar to claim that an "intelligent" gravity theory should be joined to any other existing theory in scientific discussion.

Well, how else could the singularity have known that it was 'time' to become the Big Bang other than by self-awareness?

turkey breasts feel good! (-1)

Anonymous Coward | more than 2 years ago | (#38271514)

ever feel up a turkey? gotta love those breasts!

GOBBLE GOBBLE!

Wow. (3, Funny)

Frosty Piss (770223) | more than 2 years ago | (#38271540)

I'm envious of anyone who actually understands anything the summary is talking about.

Re:Wow. (2)

somersault (912633) | more than 2 years ago | (#38271626)

It's pretty much high school physics. Spin yourself on an office chair and observe what happens as you move your arms or legs closer and further away from the center of your rotation. Admittedly the summary did phrase things such that I realised better why spreading out your mass changes your rotational velocity..

Re:Wow. (1)

bonch (38532) | more than 2 years ago | (#38271898)

Don't worry, I'm sure another "Google is great" or "Copyright sucks" article is in the queue.

The Bullet Cluster (5, Insightful)

Anonymous Coward | more than 2 years ago | (#38271586)

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 [discovermagazine.com]

We have a useful phrase to describe new fields whose energy warps spacetime: “dark matter."

Re:The Bullet Cluster (4, Informative)

jpmorgan (517966) | more than 2 years ago | (#38273054)

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.

Yet another MOND (1)

Cyberax (705495) | more than 2 years ago | (#38271642)

Yet another MOND which doesn't explain the Bullet Cluster and gravitational lensing curves.

Re:Yet another MOND (1)

MightyMartian (840721) | more than 2 years ago | (#38271698)

Yup. Theories trying to handwave dark matter seem to pop up about once a month these days, and each and every time they seem to be in some sort of timewarp from before recent observations.

Come on, you lazy ass cosmologist-wannabes, read the flippin' literature before you try to declare "I've got rid of dark matter!"

Re:Yet another MOND (3, Funny)

msauve (701917) | more than 2 years ago | (#38271850)

"I've got rid of dark matter!"

Yeah. That's implausible. After carving up the turkey recently, the last thing left was the dark matter. Everyone seems to like the white matter better.

Re:Yet another MOND (0)

Anonymous Coward | more than 2 years ago | (#38272344)

I've got rid of dark matter!

Hey, me too! And then there was this fluhing water sound.

Re:Yet another MOND (3, Insightful)

Spykk (823586) | more than 2 years ago | (#38272730)

Theories trying to handwave dark matter seem to pop up about once a month these days

Can you blame them? We found a bunch of stuff that doesn't fit our model for how the universe works so instead of invalidating our model we just assume that there is something invisible influencing our numbers. I won't pretend like I know what is really going on but blaming some undetectable third-party when your model fails feels like grasping at straws to me.

Re:Yet another MOND (0)

Anonymous Coward | more than 2 years ago | (#38271710)

I wouldn't be so quick to say that. While this certainly relies on magic constants backed into observational data, it deserves more thought than went into your knee jerk pair of posts. I think it'll fail on further analysis, but that's not a foregone conclusion, and not a threat to your meager funding.

Re:Yet another MOND (4, Insightful)

Cyberax (705495) | more than 2 years ago | (#38271780)

Nope. A theory which explains away the dark matter MUST explain the observable effects of: http://en.wikipedia.org/wiki/Bullet_Cluster [wikipedia.org] Then it should explain discrepancy between small and large galaxies.

Only after it passes these two tests it could be discussed seriously. Yet another "I can haz explain rotation curves!!!" theory is definitely not interesting.

Gravity and the Casimir effect (1)

Anonymous Coward | more than 2 years ago | (#38271942)

I remember reading some time ago that gravity isn't a pull, but a pushing effect. Essentially, gravity is a macro version of the Casimir effect.

"Solves" one issue of dark matter only (5, Interesting)

thegreatemu (1457577) | more than 2 years ago | (#38271792)

Disclaimer: I do experimental searches for dark matter for a living, so I may be biased in my judgement of these types of papers that crop up so often. There was a similar paper a few weeks ago from someone claiming that quantum vacuum polarization could account for dark matter PhysOrg link [physorg.com].

The issue with both of these explanations, is that they only address galactic rotation curves. Those are among the first and easiest to explain indications of the need for something like dark matter, but are not the strongest by a long shot. For instance, this guy's explanation can't explain things like the famous Bullet cluster [wikipedia.org], nor can they explain the evolution of structure formation or the spectrum of fluctuations in the cosmic microwave background [nasa.gov] which, in the field, are considered much stronger constraints.

The Cold Dark Matter (CDM) theory of cosmology fits all of the astrophysical measurements reasonably well, and has a nice tie-in to supersymmetric particle physics, which is one of the current leading theories. No one in the field will take any new theory seriously until it can reproduce ALL the phenomena at least as well as the current model (which of course is exactly how the scientific process is supposed to work!)

Re:"Solves" one issue of dark matter only (3, Insightful)

globaljustin (574257) | more than 2 years ago | (#38272134)

hey thanks for your contribution...seems like you know what you're talking about

I want to respond to this:

"this guy's explanation can't explain things like X, nor can they explain Y which, **in the field**, are considered much stronger constraints."

I dont want to squabble about X & Y...but ask you if X & Y were re-examined in a context that was absent a need for Dark Matter of any kind, is it possible that the researchers of X & Y would find another way to explain the observations?

Of course, yes, we could find that observations of the Bullet Cluster can fit a model sans-dark matter once we apply a comprehensive understanding of black holes...or not.

My point is, Dark Matter is as Dark Matter does...if its not an option, those PhD dissertations on galaxy collision physics are going to get written anyhow, and whatever explanation we can find will be the best until we find something better...

sure the CDM Theory of Cosmology fits observations...we can reverse engineer ANY result we want with the data analysis tools available...the point of my post is simply to ask, "What is more important to you, volume of published research on a topic or mathematic/scientific fitness?"

Your answer to my question is also the answer to your own questions of the External Validity of Carati's equations.

Re:"Solves" one issue of dark matter only (2)

Tomato42 (2416694) | more than 2 years ago | (#38272234)

From wikipedia Bullet cluster:

At a statistical significance of 8, it was found that the spatial offset of the center of the total mass from the center of the baryonic mass peaks cannot be explained with an alteration of the gravitational force law.

In other words, the theory the guy is proposing is akin to Newtonian laws when we have Special Relativity. Non story.

Re:"Solves" one issue of dark matter only (0)

Anonymous Coward | more than 2 years ago | (#38272358)

I won't give up my electric universe theory until you pry it out of my cold dark matter.

Re:"Solves" one issue of dark matter only (1)

phatsonic (2499966) | more than 2 years ago | (#38272448)

But doen't the scientific process also mean, that we have to think about a theory and its possibilities before dismissing it?

Re:"Solves" one issue of dark matter only (1)

Paracelcus (151056) | more than 2 years ago | (#38272512)

I have been (and am) quite leery of DM and I have my reasons for being leery, not the least of which is the complete lack of directly observable evidence (it's dark) just doesn't cut it, tenuous clouds of heavy molecules, blah, blah what ever. When the main reason for a theory is the (follow the leader) effect and not so much a gravetic signature of ambiguous origin, I'll call all the current theories not much more than mental-masturbation.

Re:"Solves" one issue of dark matter only (1, Interesting)

Bigby (659157) | more than 2 years ago | (#38272838)

I've never believed in dark matter or dark energy. Physicists made it up to explain something that could not be explained by our current theories. The fact that they needed to be made up shows that our current model of the universe is wrong. It is patchwork science. It may work for now, but the more patches you add, the further you will get from the real truth.

Why So Implausible? (0)

A. B3ttik (1344591) | more than 2 years ago | (#38271794)

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. So an entire new classification of matter that no one has ever (or can ever) seen, felt, or observed was created to satisfy this one anomaly. And yet, this is the industry standard, that 90% of all matter must be Dark Matter just because someone screwed up when calculating orbital momentum.

What's more implausible, that 90% of matter is something that we'll never observe except, conveniently, through the orbital momentum of stars, or that galaxies have a noticeable gravitational pull on objects in nearby galaxies over billions of years?

There is other evidence. (5, Informative)

pavon (30274) | more than 2 years ago | (#38271974)

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:There is other evidence. (4, Interesting)

khipu (2511498) | more than 2 years ago | (#38272874)

* Lack of MACHO gravitational lensing

The MACHO-based argument is that there can't be enough of those objects around in order to explain galactic rotation. But this paper, in effect, says that you don't need them. So that observation seems consistent with this paper.

* Existence of unexpected gravitational lensing in Bullet Cluster.

The Bullet Cluster result shows that some form of unobservable matter exists. But we already know that: brown dwarfs, rogue planets, etc.: that kind of "dark matter" has been observed, just not in the amounts to explain galactic rotation.

It is not surprising that somewhere in the universe, you might get very large clusters of such objects. The bullet cluster might just be composed of such objects. And at those distances, you couldn't observe baryonic dark matter. In fact, if you rip out most of the hydrogen from a cluster, it is perhaps not surprising that you end up with a lot of cold, dark lumps of baryonic matter.

* CMBR measurements * and more.

You have to separate explaining observations from testing hypotheses. CMBR measurements can be explained within the framework of non-baryonic dark matter. But that does not necessarily imply that they provide evidence for non-baryonic dark matter, since there are many other possible explanations.

I'm not saying that this paper is true or not. But if you want to argue against it, you need to sharpen your arguments.

Re:Why So Implausible? (1)

Statecraftsman (718862) | more than 2 years ago | (#38272078)

This. I think the author of the article is actually using dismissiveness as a device to disarm people. If he downplays it people perhaps won't feel as threatened. "It's crazy" but maybe it's true.

I would like some confirmation though that there really is NO other evidence of dark matter.

Perhaps even if this theory doesn't stand the test of time, it will highlight the actual reasons dark matter has grown to become so accepted in our understanding of galactic mechanics.

Re:Why So Implausible? (1)

Anonymous Coward | more than 2 years ago | (#38272450)

We are all agreed that your theory is crazy. The question that divides us is whether it is crazy enough to have a chance of being correct.
-Niels Bohr

Re:Why So Implausible? (1)

Daniel Dvorkin (106857) | more than 2 years ago | (#38272122)

Dark Matter was created for the sole purpose of explaining the orbital momentum of stars. There is NO other evidence for it.

As it happens, the post immediately above yours [slashdot.org] indicates otherwise; there's a lot of other evidence for it, or at least, there are a lot of other observations which fit nicely with the theory. Be careful about saying "there's no evidence" or "there's no other evidence" about pretty much anything in science, really -- there is so much new data coming in all the time that there's a good chance you're wrong.

Re:Why So Implausible? (2)

bucky0 (229117) | more than 2 years ago | (#38272252)

There is NO other evidence for it. So an entire new classification of matter that no one has ever (or can ever) seen, felt, or observed was created to satisfy this one anomaly. And yet, this is the industry standard, that 90% of all matter must be Dark Matter just because someone screwed up when calculating orbital momentum.

What's more implausible, that 90% of matter is something that we'll never observe except, conveniently, through the orbital momentum of stars, or that galaxies have a noticeable gravitational pull on objects in nearby galaxies over billions of years?

Which one is it? Also, the guy below beat me to the observations.

Re:Why So Implausible? (4, Insightful)

radtea (464814) | more than 2 years ago | (#38272516)

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.

False. So completely and entirely false that I really can't see you being anything other than a troll, but on the theory that sufficiently advanced ignorance is indistinguishable from malice, I'll point out what several others have already done above: the Bullet Cluster, various details of the CMB, and at various aspects of large-scale structure in galaxy clusters, up to and including the closure of the universe itself, are all evidence for Dark Matter of various kinds.

So all you've done here is declare, "I am completely ignorant of almost all of observational cosmology and THIS is my opinion on Dark Matter..."

After reading the first half of that sentence no one who knows anything about Dark Matter is going to be the least bit interested in what you have to say in the second half.

Here's my theory (0)

Anonymous Coward | more than 2 years ago | (#38271848)

The Big Bang produced a shock wave comprised of dust and stuff (or a gravity wave?) that has lots of mass (oh, the missing mass you say?) that is expanding away from the center of the big bang explosion faster than the speed of light (so we can't see it). This globe-shaped expanding shock wave is massive enough to have a gravitational effect on the galaxies that are being pulled towards it with the galaxies farther away from us accelerating faster and the galaxies closer to us more slowly in accordance to the inverse square law of gravity. I predict that as the farthest galaxies get close to the shock wave they will exceed the speed of light and DISAPPEAR FROM VIEW.

That's my theory.

Remember, you heard it first here on /.

If this is already a known theory then I agree with it.

Re:Here's my theory (0)

Anonymous Coward | more than 2 years ago | (#38272184)

Don't bogart that joint, man!

Re:Here's my theory (1)

Rockoon (1252108) | more than 2 years ago | (#38272222)

that is expanding away from the center of the big bang explosion

There is no such thing as the center of the big bang. Until you at least understand that, perhaps you shouldn't waste your time coming up with cosmology theories.

Anybody want's to wager? (2, Interesting)

quax (19371) | more than 2 years ago | (#38271868)

This is based on Einstein's field equation using perturbation theory to construct a solution for the examined case.

My bet is on general relativity once again delivering the goods. Quite a strike against the case for dark matter.

Re:Anybody want's to wager? (0)

Anonymous Coward | more than 2 years ago | (#38272070)

My bet is on general relativity once again delivering the goods. Quite a strike against the case for dark matter.

But the only citation for the methods used is the author's own previous work. IOW, the previous work is either too new and untested or too incorrect to have even made it into a review article.

Re:Anybody want's to wager? (-1)

Anonymous Coward | more than 2 years ago | (#38272098)

no speaky english!

So called scientists (0)

Anonymous Coward | more than 2 years ago | (#38271890)

These so called scientists, all these long words and complex equations and they still have yet to make a working hyperdrive!

Re:So called scientists (1)

gapagos (1264716) | more than 2 years ago | (#38272048)

The problem is not that we can't make a hyperdrive, the problem is that we need to build a flux capacitor first.

Don't know anything about Physics (2)

Oswald McWeany (2428506) | more than 2 years ago | (#38272338)

Granted, I don't know anything about physics so my comment is probably unwanted and useless; however.

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."

OK, it's more than just that- and from people way more knowledgable than me; however, I've always wondered if it was just a stop-gap explanation that would one day be disproven. (which it hasn't been yet).

I'm grabbing my pop-corn, turning on physics Pay Per View and cheering on the anti-dark matter brigade in this fight. I'm hoping dark-matter turns out to be false. Not that I'm matterracist.

Good (1)

Layth (1090489) | more than 2 years ago | (#38272616)

I am in the same boat as you.

Dark matter always sounded too far fetched for me.
The same is true for superstring theory.. it's not something I can get behind.

Maybe I have just contemplated the presence of a void for too long.

Re:Don't know anything about Physics (5, Insightful)

cje (33931) | more than 2 years ago | (#38272752)

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.

Re:Don't know anything about Physics (2)

Carnildo (712617) | more than 2 years ago | (#38273018)

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."

It was discovered in 1933 that if we add up the mass of all the stars in a galaxy and run it through either Einsteinian or Newtonian gravity, there isn't enough of it to explain the paths of those stars. "Dark matter" simply means any form of matter that doesn't emit light (the Earth, for example, is a lump of baryonic dark matter), and originally it was expected that there were enough cold gas clouds, failed stars, stray planets, and the like (collectively known as "baryonic dark matter") to explain things.

The problem with dark matter is that astronomers have since gotten a fairly good idea of how much baryonic dark matter there is, and there's nowhere near enough. Thus, the various suggestions of non-baryonic dark matter and modified gravitational theories.

consensus??? (1)

khipu (2511498) | more than 2 years ago | (#38272634)

Science is not made by consensus, it is made by logic, mathematics, experiment, and observable facts. If you cannot provide clear, correct, and reproducible experiments and math, you aren't doing science.

There is no "consensus on dark matter", since nobody knows what causes galactic rotation to be the way it is. Any ideas of what dark matter might be at this point is just guesswork. You are entitled to your preferences, but just because a lot of people have certain preferences doesn't make those preferences "science".

This wrong-headed notion of a "consensus" in science has increasingly polluted science. I think it started with soft sciences like sociology and climatology, both of which lack simple, reproducible experiments, well-defined theories, and mathematical theories. Instead of providing those, "scientists" with political agendas then just ended up saying to politicians "we can't really prove it, but we are the experts; believe us". From there, this has spread to other sciences, including, sadly, physics.

My pet theory posted sci.physics 6-11-2011 (0)

Anonymous Coward | more than 2 years ago | (#38272640)

Eliminate singularities, inflation, dark matter, dark energy and dark flow -
posted sci.physics 6-11-2011
****

1. Singularities in black holes don't exist because at the center of the
black hole is near zero gravity and this would cause the material
to pull back leaving a bubble.

That gets rid of the ONLY known singularity in the present universe.

2. In the past, the expansion of the universe could be reversed to a single
point causing a singularity. This can be got rid of if two massive black
holes collided at high speed creating the universe.
Each black hole did not have within it a singularity.
So no singularity even at the beginning of the universe existed.

That gets rid of the ONLY known singularity at the birth of the universe.

3. The two original giant universe creating black holes had a head on
collision at many times the speed of light such that the entire
material universe from each black hole had to go through each other
creating uniformity and a debris field that for a short time expanded
at a speed greater than c. This was no inflation as such but has the same
outcome and eminently suitable for simulations.

4. The bulk of this material that exploded is still in the periphery
like in all explosions as invisible droplets of black hole material.
They are probably the average size of current black holes
because we know the galaxies formed around black holes
and not the other way around and they existed way back
at the birth of the universe for the galaxies to form around them.
If they existed a few hundred thousand years earlier, then nearly
all of them would be at the periphery of the universe.
These numerous giant black hole droplets of material is now pulling
all the material at the center giving the impression
of an accelerating universe full of dark energy.

So dark energy comes from the pull of the outside shell of 'droplets'
of black hole material that got ejected at the first stages
of the big bang event.

5. If there is vast amounts of material at the periphery,
then there is a gravitational pull from the periphery which is yanking
at all objects such that local gravity is added to an all pervasive
and existing uniform gravitational field that comes from the periphery.
We could be mistaking this field for dark matter.

6. Dark flow implies the two black holes that crashed into each other
to make our universe were of unequal mass. This implies that we are
not at the center of mass of the entire system and so we are being
pulled towards the center of mass; and this can happen without
there being a need for a second universe out there.

So thats just 6 paragraphs to explain away singularities, inflation,
dark matter, dark energy and dark flow.

Remember this Slashdot story? (2)

Guppy (12314) | more than 2 years ago | (#38272814)

Remember this story on Slashdot from 2005?
http://science.slashdot.org/story/05/10/10/1052224/good-bye-dark-matter-hello-general-relativity [slashdot.org]

"The CERN newsletter reports that a new paper by scientists at the University of Victoria has demonstrated that one of the prime observational justifications for the existence of dark matter can be explained without any dark matter at all, by a proper use of general relativity! What does this imply for cosmology and particle physics, both of which have been worrying about other aspects of dark matter?"

Impressive sounding claims that raised a big hoo-ha on Slashdot (and are echoed in similar replies to this story), until it was pointed out that the equations contained a mistake, such that the galaxy they modeled behaved as if it had a disk-shaped singularity embedded in it. A mistake that accounted for the observed effects in the model.

This sort of physics paper is exactly the type of preliminary result that needs to be mulled over before it front-page attention. It's pretty close to being flame-bait (and thus just ends up making everyone look stupid, except for the handful of physics experts who knew what they were talking about).

Lets look at some possibilities (1)

PhilHibbs (4537) | more than 2 years ago | (#38272964)

The factors in an orbit : the current velocity body, and the force acting on it (and how that velocity and force change over time). If the velocity is perpendicular to the centre of mass, and if force is just right, the body will orbit in a circle. If it is too strong, it will fall in on an elliptical orbit, and if it is too weak or the object is moving too fast then it will fall outwards on an elliptical orbit or hyperbolic escape arc.

So, presumably we know the velocity of the stars at a particular distance out, but our calculations say that at that speed they should not be in a stable orbit at that radius.

Firstly, who says that they *are* in a stable, near-circular orbit? If they are already in elliptical orbits, then they will mostly be going faster than they would if they were in a circular orbit at that position.

What do we know about the velocity of the stars? Do we just know their speed? Do stars weave about as they go around the galaxy, caught in a complex dance with all the neighbouring stars? Could this account for faster apparent motion than a simple orbit around the galaxy?

What about relativity? Half the mass of the galaxy is 30,000 light years away, does that mean that its gravitational influence has to take into account this 30,000 year time delay in the gravitational influence reaching us? If you figure out the gravitational effect of the galactic core based on where we were 30,000 years ago, does that change the force vector? Or, am I just being simple-minded in thinking of gravity travelling like that?

Galaxies' speed equals light? (0)

Anonymous Coward | more than 2 years ago | (#38273050)

I'm genuinely interested, how is it established that galaxies speed equals that of light?

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