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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)."

3 of 302 comments (clear)

  1. Re:"Intelligent" gravity force by Anonymous Coward · · Score: 5, Informative

    It's called Intelligent falling.

  2. There is other evidence. by pavon · · 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.

  3. Re:what's going on in italy lately? by Anonymous Coward · · 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