
Spinning black hole powers jet by magnetic flux - dnetesn
https://phys.org/news/2020-08-black-hole-powers-jet-magnetic.html
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peter_d_sherman
>"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...

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mtreis86
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?

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DiabloD3
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.

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gbrown
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.

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DiabloD3
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.

