Cosmology: giant black hole jets of energy may be explained (Introduction)

by David Turell , Friday, May 21, 2021, 01:11 (1072 days ago) @ David Turell

A recent research finding on one black hole:

https://www.quantamagazine.org/physicists-identify-the-engine-powering-black-hole-energ...

"Both images show the glowing plasma around the supermassive black hole at the center of the galaxy M87, whose giant jet rises outside the frame. Unlike in the first photo, the ring in the new image has stripes, indicating that the light is strongly polarized.

"Experts say the spiral pattern of the stripes results from a strong, orderly magnetic field around the M87 black hole, and that this represents the first significant empirical evidence in favor of a popular 44-year-old theory of jet launching, known as the Blandford-Znajek process.

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"...the new observations point to one of two rival versions of the Blandford-Znajek process that have been developed and explored in hundreds of computer simulations in recent decades, known as the MAD and SANE jet-launching scenarios. These competing ideas paint opposing pictures of a black hole’s milieu and, in particular, the origin and strength of its magnetic field.

"SANE models, which assume weaker fields, were long considered more plausible. But the strongly polarized light in the Event Horizon Telescope’s new photo points to strong magnetic fields, and therefore to the MAD version of events. The new image “seems to heavily favor MAD models,” said Alexander Chen, a theoretical astrophysicist at the University of Colorado who is not part of EHT.

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“'The black hole in M87 is about the size of our solar system,” Issaoun said, yet it produces a 5,000-light-year-long current of white-hot plasma. That’s like the Statue of Liberty popping out of a marble. Some 3 trillion trillion trillion joules of energy flow up the jet each second — 500 trillion times more energy than the entire human population burns in a decade. “How could something so tiny be so powerful?”

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"With Kerr’s equations in hand, Blandford and Znajek showed that when magnetic field lines from the accretion disk fall onto the spinning hole, the black hole’s rotation will wind the field lines into a helix oriented along the hole’s rotation axis. Magnetic fields in motion generate a voltage, so a current of electrons and positrons will start flowing through the helix away from the black hole in both directions. This is the jet.

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"But the Event Horizon Telescope’s new image of polarized light from around M87’s black hole points firmly in the MAD direction. Polarized light vibrates in a single plane, typically after reflecting off a surface or when emitted by charged particles whose paths are curving uniformly in a magnetic field. The spiral pattern in the photo conveys that the light’s plane of vibration rotates as you look at different places around the ring, exactly as expected if particles radiating the light are gyrating around magnetic field lines that themselves have a coherent spiral pattern.

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"Studying the particles may be necessary for working out the jets’ overall structure and their effect on the galaxies and intergalactic space they pierce through. Many jets are thin and bright all along their length. “How does it shine? How do we see it?” Chen wonders. In the case of M87’s jet, “we see it very clearly in the sky. Sometimes it breaks into knots, and sometimes it’s continuous, but it’s remarkably straight and thin. Understanding that will definitely help us understand how it interacts with the galactic and intergalactic medium — how it transfers energy to the galaxy, for example.'”

Comment: Our massive universe contains some massive fireworks. dhw has wondered in the past why God created all these events when all He wanted was humans. I don't know and I don't wonder. I assume God did this for His own reasons and they are a reasonable part of the process.