back to article Thought black holes were donut-shaped? It turns out they're more like deadly fountains

Black holes aren’t shaped like donuts after all, and actually look like water fountains instead, according to new research. “Previous theoretical models set a priori assumptions of rigid donuts,” said Keiichi Wada, a theoretical physics professor at Kagoshima University, Japan. Scientists believed that as surrounding matter is …

  1. Martin Gregorie Silver badge

    Nice work by Atacama and Kagoshima

    Sounds like an excellent bit of science. Well done to both observers and theoreticians. That deserves a few cold ones.

  2. oldtaku

    Well, the accretion disk anyhow

    To be clear, the black hole itself is still extremely spherical. This is the gas around it - the accretion disk mentioned, which now may look like a disk with party sparklers. Hey, it's the only part you can see, anyhow.

    1. Anonymous Coward
      Anonymous Coward

      Re: Well, the accretion disk anyhow

      > "Hey, it's the only part you can see, anyhow."

      You CAN see a black hole, but you gotta get reeeal close...

      1. Version 1.0 Silver badge

        Re: Well, the accretion disk anyhow

        And you know what happens when you try to take a selfie that close ...

    2. Kevin McMurtrie Silver badge

      Re: Well, the accretion disk anyhow

      Probably not very spherical if everything hits it with a spin.

    3. Cuddles Silver badge

      Re: Well, the accretion disk anyhow

      "To be clear, the black hole itself is still extremely spherical."

      No it isn't. The only kind of black hole that can be spherical is a perfectly isolated one with zero charge and zero angular momentum, and it's impossible for that to exist in the real world. It's been known that neither the singularity or event horizon in real black holes are actually spherical for quite a while.

      It's also worth noting that this article is completely wrong. From the paper:

      "which would explain the longstanding mystery of the physical origin of the AGN torus."

      Note that "torus" is the technical term for "donut-shaped". The paper doesn't say anything about the accretion disk being fountain-shaped instead of donut-shaped, the fountain is the explanation for how the disk becomes donut-shaped. Without that, it wasn't understood why it would be a thick donut instead of the expected thin disk.

    4. Anonymous Coward
      Anonymous Coward

      Re: Well, the accretion disk anyhow

      "the black hole itself is still extremely spherical"

      can a singularity be correctly described as having a shape at all? surely its a point in spacetime and has no measurable physical charactoristics in any of the 4 dimensions we understand.

      1. Brewster's Angle Grinder Silver badge

        Re: Well, the accretion disk anyhow

        "...can a singularity be correctly described..."

        No, I'm not sure singularities can be described. That's the point: they're placeholders for a physical process yet to be uncovered.

      2. richardcox13

        Re: Well, the accretion disk anyhow

        > can a singularity be correctly described as having a shape at all?

        Correct, it can't.

        But what is usually meant is the event horizon around the singularity. And that certainly can have a well defined shape (as noted above in the zero charge, zero angular momentum case it would be a sphere).

  3. m0rt Silver badge

    "A big killer fountain"

    So not like a big killer plughole then?


    Damned science.

    1. Anonymous Coward
      Anonymous Coward

      Next they'll be saying it isn't even a proper hole!

  4. Pascal Monett Silver badge

    Interesting detail

    Incoming gas is labelled "molecular", outgoing fountain gas is labelled "atomic".

    I can readily imagine that the maelstrom around a black hole is the absolute worst place to be, but are gas molecules already torn into atoms at that stage ? Or is that just another way of saying "plasma" ?

    1. Anonymous Coward
      Anonymous Coward

      Re: Interesting detail

      They've pretty much described current flow in a toroidal plasma pinch.

      1. mikeymac

        Re: Interesting detail

        Fellow traveler!

    2. Trev 2

      Re: Interesting detail

      These science bods need to change the way they describe things like "cold molecules" - can't imagine anything getting dragged into a blackhole is remotely cold!

      Not sure about the other bit, but wouldn't be surprised if they are split into their component parts way beyond atoms? Really can't imagine many gas molecules surviving getting too close and still intact.

  5. lglethal Silver badge

    Wait until they find "The Keep Off The Lawn" signs...

    Ahhh the scientists finally saw the "Please Dont Play In The Fountain" signs, did they?

  6. Destroy All Monsters Silver badge

    "greedy black holes gobbling matter"

    So you are saying there interesting computational processes happening on the event horizon?


    For an idea similar to gravastars implying actually torus-shaped black holes, see here:

    Are Black Holes Actually Dark Energy Stars? and of course Jimbo's Noisy Infobunker.

    Sat 1 Dec 12:07:30 CET 2018

    1. Pascal Monett Silver badge

      All of those theories appear to be an attempt to do away with the singularity using dark energy as an excuse in order to remove the destruction of information that was supposed to happen in the singularity and is not compatible with the quantum rules of the Universe.

      But that destruction has been recognized as wrong by Hawking himself, so these theories have no more object.

      Plus, the Event Horizon Telescope has not led to new, Earth-shattering revelations about the Milky Way's central black hole, so it looks like it is indeed just a black hole.

      Opinion to be revised if scientific news warrants.

  7. 89724102172714182892114I7551670349743096734346773478647892349863592355648544996312855148587659264921

    Fountains gushing out of black holes is worrying, but an Interstellar remake would be deadly

  8. Matthew Taylor

    It turns out that...

    This will sound like a silly nitpick, but I dislike the phrase "It turns out that..." - especially when used in science articles. A few years ago it "turned out that" black holes were doughnut shaped, now it "turns out" they're like a fountain. Both times, the phrase implies that now we've finally got it right, and the job is done. It's not done, science is never done, and it's extra definitely not done when studying something like black holes.

    (Not to take anything away from the actual research discussed here, which is excellent and fascinating).

  9. Frumious Bandersnatch Silver badge

    I dunno about this report

    Seems a bit thin in places.

  10. aj69

    Who picks up the coins that people throw in the black hole wishing well?

  11. Anonymous Coward
    Anonymous Coward

    As anyone knows

    Its dimensions all the way down.

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