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Spinning black hole powers jet by magnetic flux

22 points by dnetesn 6y ago

DiabloD3 6y ago
This is a great paper. I just want to know how cosmologists are going to handwave away that this isn't generated by some unknown gravitational phenomenon, that gravity does not scale to the size required for this, and that the electromagnetic force is the driver of all phenomenon at the solar or galactic scale, including this.
- gbrown 6y ago
  I mean, that is what the article appears to say, no? Magnetic forces carried by the plasma surrounding the black hole interacting with frame-dragged spacetime.
  - DiabloD3 6y ago
    The actual paper doesn't say that, Phys.org coverage is a bit hit and miss sometimes, trying to dumb it down enough for the common reader (but not nearly as much as the news media does). The paper is mostly about the actual record of the observations. Based on the description of the authors, it seems they're witnessing a huge z-pinch being formed out of a (most likely multi-layered) toroidal plasma field. Conceptually, this phenomenon and experimental double layer Hail effect thrusters are pretty similar, and exploit the same area of plasma physics. The jet doesn't switch on until you pump enough energy into it, similar to how plasma goes from glow mode to arc mode relatively quickly, but forms a self-reinforcing helical beam perpendicular to the plasmoid donut. None of this necessarily requires gravity, even to stay cohesive at this immense scale.
- QuadmasterXLII 6y ago
  I've seen allusions to this theory a couple times on hacker news. I'd be interested in an exposition of the math behind it. For example, since electromagnetism drives all phenomena at solar scale, it should be possible to derive Kepler's laws from this theory. Could you link such a derivation?
- imglorp 6y ago
  Wait, I think the assertion is EM drives some _some_ phenomena at those scales. Are you suggesting it's the driver of _all_ phenomena?
mtreis86 6y ago
So its like a giant automotive coil, storing up magnetic energy until it can't be held then dumping it in a wide bandwidth electromagnetic emission?
peter_d_sherman 6y ago
>"Black holes are at the center of almost all galaxies that have been studied so far. They have an unimaginably large mass and therefore attract matter, gas and even light. But they can also emit matter in the form of plasma jets—a kind of plasma beam that is ejected from the center of the galaxy with tremendous energy. A plasma jet can extend several hundred thousand light years far into space." PDS: That's interesting... Intense gravity (and solid objects AKA "matter" that would be attracted by the gravity of the black hole) going one way -- and a plasma vortex, equal-and-oppositely, going the other way... If this article is true, then it makes me wonder if the reverse could be accomplished -- create a plasma vortex going one way, and get a corresponding black hole behind it...

22 points by dnetesn 6y ago

This is a great paper. I just want to know how cosmologists are going to handwave away that this isn't generated by some unknown gravitational phenomenon, that gravity does not scale to the size required for this, and that the electromagnetic force is the driver of all phenomenon at the solar or galactic scale, including this.

gbrown 6y ago
I mean, that is what the article appears to say, no? Magnetic forces carried by the plasma surrounding the black hole interacting with frame-dragged spacetime.
- DiabloD3 6y ago
  The actual paper doesn't say that, Phys.org coverage is a bit hit and miss sometimes, trying to dumb it down enough for the common reader (but not nearly as much as the news media does). The paper is mostly about the actual record of the observations. Based on the description of the authors, it seems they're witnessing a huge z-pinch being formed out of a (most likely multi-layered) toroidal plasma field. Conceptually, this phenomenon and experimental double layer Hail effect thrusters are pretty similar, and exploit the same area of plasma physics. The jet doesn't switch on until you pump enough energy into it, similar to how plasma goes from glow mode to arc mode relatively quickly, but forms a self-reinforcing helical beam perpendicular to the plasmoid donut. None of this necessarily requires gravity, even to stay cohesive at this immense scale.
QuadmasterXLII 6y ago
I've seen allusions to this theory a couple times on hacker news. I'd be interested in an exposition of the math behind it. For example, since electromagnetism drives all phenomena at solar scale, it should be possible to derive Kepler's laws from this theory. Could you link such a derivation?
imglorp 6y ago
Wait, I think the assertion is EM drives some _some_ phenomena at those scales. Are you suggesting it's the driver of _all_ phenomena?

mtreis86 6y ago

So its like a giant automotive coil, storing up magnetic energy until it can't be held then dumping it in a wide bandwidth electromagnetic emission?

peter_d_sherman 6y ago

>"Black holes are at the center of almost all galaxies that have been studied so far. They have an unimaginably large mass and therefore attract matter, gas and even light. But they can also emit matter in the form of plasma jets—a kind of plasma beam that is ejected from the center of the galaxy with tremendous energy. A plasma jet can extend several hundred thousand light years far into space." PDS: That's interesting... Intense gravity (and solid objects AKA "matter" that would be attracted by the gravity of the black hole) going one way -- and a plasma vortex, equal-and-oppositely, going the other way... If this article is true, then it makes me wonder if the reverse could be accomplished -- create a plasma vortex going one way, and get a corresponding black hole behind it...