Register to reply

Black holes and poles...

by RickBman
Tags: black, holes, poles
Share this thread:
RickBman
#1
Jul4-13, 04:10 PM
P: 12
Im a little confused...If a black hole has a true point of singularity how does it have magnetic poles, and how does it have jets of charged particles shooting out from its poles,how does this escape the event horizon if light cant? are black holes real?????
Phys.Org News Partner Astronomy news on Phys.org
Magnetar discovered close to supernova remnant Kesteven 79
Image: Hubble looks at light and dark in the universe
Mixing in star-forming clouds explains why sibling stars look alike
Naty1
#2
Jul4-13, 04:44 PM
P: 5,632
Check out the discussion here.....

http://www.physicsforums.com/showthr...accretion+disk

it's one of many, so try a search..


If a black hole has a true point of singularity....

yes..and no..... depends what you think 'singulariy means.....it's most likely a place where our equations of GR and QM are no longer applicable..indicating divergences....not infinite anything...more below.....

how does it have magnetic poles, and how does it have jets of charged particles shooting out from its poles,how does this escape the event horizon if light cant?

all that is stuff exterior to the BH, from interactions between the surrounding accretion disk and gravitational effects of the black hole itself...As matter and radiation in space falls towards the BH it usually rotates[ like water going down a drain does] because the black holes are usually rotating and 'frame dragging' space time along nearby outside.....jets emerge from the centers of rotation:

BH accretion disk theory
http://arxiv.org/pdf/1104.5499v3.pdf

The radiation we receive from quasars and microquasars comes not from the black holes themselves, but instead originates in the accretion disks which surround them
(see Figure 1). In these accretion disks, angular momentum is gradually removed by some presumably (although not necessarily [48]) dissipative process, causing matter to spiral down into the black hole, converting its gravitational energy into heat, and then, by various processes, radiating this energy.7 The radiation subsequently leaks through the disk, escapes from its surface, and travels along trajectories curved (in space) by the strong gravity of the black hole, eventually reaching our telescopes.....However, the theoretical
understanding of disks and jets has largely proceeded separately and the physical link between the two still remains uncertain......
...


Space-like singularities are a feature of non-rotating uncharged black-holes, while time-like singularities are those that occur in charged or rotating black hole exact solutions. Both of them have the following property:
geodesic incompleteness: Some light-paths or particle-paths cannot be extended beyond a certain proper-time or affine-parameter (affine parameter is the null analog of proper time).
It is still an open question whether time-like singularities ever occur in the interior of real charged or rotating black holes, or whether they are artifacts of high symmetry and turn into spacelike singularities when realistic perturbations are added.
Rotating black holes are described by the Kerr metric.....The event horizon is rotating as though it were a solid body, so can be characterized by an angular velocity or rotation rate in RPM. For a 10 solar mass black hole rotating at the maximal rate, it is rotating at about 10^4 radians/second or about 10^5 RPM. Larger black holes will rotate at lower RPM rates, but at the maximal rotation rate, a point on the equator of the event horizon is always rotating at 1/2 the speed of light.



are black holes real?????

There is reasonable observational evidence to indicate they do exist.


Register to reply

Related Discussions
Those Jets from the poles of black holes Astronomy & Astrophysics 9
How are black holes linked to worm holes, or are they the same thing, Cosmology 6
Black holes, white holes and expansion of Universe Cosmology 7
Re: White Holes are time-reversed black holes? General Physics 0