3 ms·

Can you then explain what the author means when she says, "a voltage that draws energy up and out of the hole and along the helix. This, they claimed, is the je

by hcrisp 5y ago

Can you then explain what the author means when she says, "a voltage that draws energy up and out of the hole and along the helix. This, they claimed, is the jet — and a big asterisk on the naive notion that nothing escapes black holes"?

wumpus 5y ago
Black holes have spin, and this process is expected to slow the black hole spin, which takes energy out of it. It's not the only known way to slow black hole spin.
db48x 5y ago
The statement doesn’t mean anything because it was written by a reporter and reporters generally don’t understand what they are writing about, especially in the modern era, and especially in regards to scientific concepts. The magnetic fields can accelerate matter from the accretion disk and turn it into a jet headed away from the black hole, there’s nothing wrong with that. Maybe matter can be created by photon–photon interactions in the photon ring, and that matter can be accelerated into a jet by the magnetic field. Either way, no matter has exited the black hole; the jet is made of matter that avoided entering the event horizon. Black holes have only three macroscopic quantities which are observable from the outside: mass, rotational kinetic energy, and electric charge. Since it would be pretty hard to arrange for matter of only one electric charge to fall into a black hole, the charge of the average black hole is believed to be pretty much neutral at all times. The mass of the black hole is inaccessible, because it is concentrated at the singularity. Or possibly in the firewall, if black holes have firewalls. That leaves the rotational kinetic energy as the source of the energy that powers the jets. The jets would last until the rotation of the black hole slows enough that the magnetic fields aren’t twisted enough to maintain them.

3 ms·

Can you then explain what the author means when she says, "a voltage that draws energy up and out of the hole and along the helix. This, they claimed, is the je

by hcrisp 5y ago

wumpus 5y ago
Black holes have spin, and this process is expected to slow the black hole spin, which takes energy out of it. It's not the only known way to slow black hole spin.
db48x 5y ago
The statement doesn’t mean anything because it was written by a reporter and reporters generally don’t understand what they are writing about, especially in the modern era, and especially in regards to scientific concepts. The magnetic fields can accelerate matter from the accretion disk and turn it into a jet headed away from the black hole, there’s nothing wrong with that. Maybe matter can be created by photon–photon interactions in the photon ring, and that matter can be accelerated into a jet by the magnetic field. Either way, no matter has exited the black hole; the jet is made of matter that avoided entering the event horizon. Black holes have only three macroscopic quantities which are observable from the outside: mass, rotational kinetic energy, and electric charge. Since it would be pretty hard to arrange for matter of only one electric charge to fall into a black hole, the charge of the average black hole is believed to be pretty much neutral at all times. The mass of the black hole is inaccessible, because it is concentrated at the singularity. Or possibly in the firewall, if black holes have firewalls. That leaves the rotational kinetic energy as the source of the energy that powers the jets. The jets would last until the rotation of the black hole slows enough that the magnetic fields aren’t twisted enough to maintain them.