And while this is fascinating news,
it is not the new concrete evidence I spoke of in another thread here -
"Nothing, not even light, escapes a black hole. Let's make one in Switzerland."
Xrays escape black holes.
There are also 2 event horizons, not 1.
I'm no expert, so thank you.
What is it about X-rays that makes them immune to the forces of a black hole?
The X-rays come from hot gas orbiting around the black hole in an accretion disk. As the gas orbits, magnetic stresses cause it to lose energy and angular momentum, thus spiralling slowly in towards the black hole. The orbital energy is transformed into thermal energy, heating up the gas to millions of degrees, so it then emits blackbody radiation in the X-ray band.
Once the gas gets closer than a few times the horizon radius, it plunges into the black hole, so while some X-rays can still escape just before the horizon, most are emitted a fair bit outside.
X-rays are generated by BH-star binary systems from a thermalized accretion disk. This process produces soft (low energy) X-ray radiation. In some systems, the high energy emission is much harder than that of a thermal disk and dominated by synchrotron X-rays emitted from shocked gas in the jet.
I did understand some of that and Googled the rest. Fascinating stuff.
Now, why are there two event horizons?
No one has put forth a theory yet as to why there are 2.
The answer will require some adjustments to Einstein's theories and calculations because he only predicted 1.
Current (needing adjustment) theories on black holes:
...Some black holes spin around an axis, and their situation is more complicated. The surrounding space is then dragged around, creating a cosmic whirlpool.
The singularity is an infinitely thin ring instead of a point.
The event horizon is composed of two, instead of one, imaginary spheres.
And there is a region called the ergosphere, bounded by the static limit, where you are forced to rotate in the same sense as the black hole although you can still escape....
In a spinning black hole, a central ring singularity is surrounded by two event horizons, the ergosphere and the static limit.
German physicist Karl Schwarzschild (1873-1916) first discovered the solutions of the equations of general relativity that describe non-rotating black holes.
http://hubblesite.org/explore_astronomy/black_holes/encyc_mod3_q3.htmlCross Section of a charged black hole
Photon sphere
You know, this photon sphere is pretty much like the photon sphere of a static black hole. Briefly, the photon sphere has a radius of 3/2 Rs. It is where light rays can hold unstable orbits around the black hole.
It is also the last possible orbital radius, since orbiting at any smaller radius would involve going faster than light. Hypothetically speaking, if you leveled your eye there, you would see the back of your head. Ah, the photon sphere summed up in four sentences!
Event horizons
Whoa ... horizons plural??
And just how does this happen when Schwarzschild's geometry predicted only one horizon?
Simple: when considering a black hole with charge, Schwarzschild's solution is no longer valid. We need something else!
We need...the Reissner-Nordstrøm solution! The two scientists with that namesake solution discovered that, if a small charge is added to a black hole, the event horizon shrinks and a second, inner horizon forms just above the singularity!
(Gunnar Nordström (1881 – 1923) was a Finnish theoretical physicist best remembered for his theory of gravitation, which was an early competitor of general relativity. Nordström is often designated by modern writers as The Einstein of Finland due to his novel work in similar fields with similar methods to Einstein
I've heard the inner horizon called the Cauchy horizon, and I've also heard that electrons tend to "hover" around this horizon; but I can't actually recall where I heard these things! What does this mean? Well, the event horizon is where, according to a distant observer, time seems to stop. A charged black hole just has two radii where time seems to stop.
The more charge the black hole acquires, the smaller the outer event horizon and the larger the inner event horizon gets.
If the black hole acquires a charge whose magnitude is as great as its mass (an insanely large number in the order of magnitude of 1030 coulombs), the outer and inner event horizons merge.
Should the black hole acquire a charge with a magnitude greater than its own mass, both horizons vanish and leave a naked (eek!) singularity.
This is great. This is neat. We can get rid of both event horizons! That means we can weave and bob around the charged black hole's singularity all we please without worry about needing to go faster than the speed of light.
Practicality intrudes with a catch
There's always a catch, though (you knew this was coming). The two event horizons only disappear when the magnitude of the charge of the black hole is greater than its mass.
Black holes come in 3 solar masses or more. One solar mass is roughly 1.989 x 1030 kilograms. That's huge!! You would be truly hard-pressed to amass a charge of that magnitude.
Let's just say, for hypothetical purposes, that you managed to charge up a black hole enough to disperse the two horizons. Great.
Now you have to carefully monitor everything that goes into and comes out of it and must keep a great store of charge on hand.
Something with that much charge would tend to rip apart the atoms around it, pulling the oppositely charged parts into itself.
It's almost as if the black hole is actively trying to neutralize its charge like a person would try to warm up by drinking a cup of hot liquid (mmm, hot tea!). People give electrons personalities and desires, so I see nothing wrong with doing the same for charged black holes.
http://www.gothosenterprises.com/black_holes/charged_black_hole.htmlGood overview of Wormholes and Black Holes and even White Holes(!) for those of you curious about such things -
There is now speculation that a Black Hole (or even a White Hole) may have triggered the event currently called The Big Bang.
Goodbye Big Bang, hello Black Hole Bang
A new theory claims that the Black Hole might have started Universe. As cosmologists have speculated, the Big Bang theory may be a myth and that the Universe was created by a Black Hole, from a collapsing star...
https://wordlesstech.com/goodbye-big-bang-hello-black-hole-bang/ ...And so what is new in all of this?
Thanks to new space telescopes we now have concrete evidence that
the two event horizon theory is the correct one.
From what I understand this information is due to be released this year.
Here is a graphic that very closely resembles the actual evidence found -
The regions marked 'repulsion' refer to repulsive gravity theorized to exist in Black Holes.