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Death Spiral First Evidence Of Black Hole
And Tackhead sends in this related information: "The folks at the Chandra X-Ray Observatory appear to have detected event horizons by comparing the X-ray luminosity of the accretion discs surrounding black-hole-based X-ray novae versus neutron-star-based X-ray novae during their phases of dormancy. X-ray novae are caused by ignition of fusion in the accretion discs of hot gas drawn from companion stars near black holes or neutron stars. While the novae were dormant, the discs surrounding black hole companions were observed and found to be 100 to 1000 times fainter than those surrounding neutron star companions. The conclusion: 'something' must be consuming the energy that would otherwise be expected from the disc; the most likely candidate being an event horizon."
I'm not entirely sure this isn't a troll,but... it's either this or finish an essay on Bertrand Russell.
What is your criterion for direct evidence? Part of the idea of a black hole is that I can't really see it in front of me, since it's black. Any good view of evidence would treat visual perceptions as different in degree, rather than kind, from evidence of the sort that these telescopes have turned up. I see tables in front of me all the time, but the way by which I should argue for the existence of tables and the way by which I should argue for the existence of black holes is precisely the same.
What you say about laws applying everywhere is absolutely meaningless. I can create a list of laws for *any* universe that I can describe, no matter how chaotic it may appear -- there may be a whole lot of non-computable functions in those laws, and the list might not be finite, but that doesn't mean that universe is any less bound by laws.
What's unusual about the laws in this universe is that there seem to be relatively few of them, and they're relatively simple -- at least compared to what they might be. There's no reason, though, why they *must* be so simple, or must be equally simple everywhere; the fact that we expect them to be is merely more evidence of the simplicity.
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Fusion is not an important factor in X-ray novae. Hydrogen-to-Helium fusion yields about 0.7% of the rest mass (E = mc2). Dropping something to a neutron star yields about 20% of rest mass, or about 280 times more energy than fusion. For black holes the yield is about 10%, as there is no solid surface to slam against.
X-ray novae are ignited when the accretion disk gets ionised. This makes the gas more viscous, leading to a faster lose of angular momentum and thus a faster infall. Eventually, most of the disk falls on the neutron star, producing an X-ray nova outburst.
"By definition, no astronomical object other than a black hole can possess an event horizon. The discovery comes from a detailed statistical analysis of a 1992 observation of one of the first black holes ever discovered, Cygnus XR-1, which lies 6,000 light-years from Earth..."
Also "by definition": statistical analysis of data from a black hole will give evidence of a black hole.
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Vision is the process of your brain interpreting impulses from your retina, which are created by photons reflected off the object you are seeing.
In the case of a black hole, the very definition of a black hole is an object with so high density, that the gravity well is strong enough that even light that gets inside a certain area (the even horizon) will be sucked in, and unable to escape.
Thus, any photon that comes in contact with the black hole itself will never be reflected.
You can see effects of a black hole. You can observe mass entering the event horizon. But you can never see the black hole itself.
Also, your other points are inexact. Black holes does not indicate infinite density. They indicate a density high enough that photons can't escape.
In addition, your argumentation is full of conjecture. For instance you don't give any argument for why it would be a problem if the topology of the universe is punctured with points of inifinite density, except by claiming this in some weird way violates "the very laws that the Lord decreed".
Can you point me to any works that specify "the Lord"'s views on physics, with an emphasis on astrophysics, relativity and quantum mechanics? Thought so.
The point is, our scientific theories are just that: Theories. Models that give a coherent view of the data we observe. If the models doesn't fit the data, then the models and theories have to be revised, not the data.
In the same way, could you please point me to any religious texts that explain this "well-formed universe" of yours? If you have such fait in "the Lord", surely you should have faith that whatever we observe in the universe is by his device and design, and to his liking?
But yes, they do. Our failure to understand the nature of those laws does not mean they don't exist. They violate *our* laws, the ones based on observation, experimentation and speculation, but that is not the same thing. You have to be smarter than the phenomenon you're trying to explain. We aren't yet.
Naeser's Law:
Astronomers never cease to amaze me. This guy found an event that happened for 0.2 seconds, approximately 35,194,176,000,000,000 miles away, that happened 6000 years ago. And could actually recognize the significance of the event.
From our perspective outside a black hole, matter never quite passes through a black hole's event horizon. That is because time slows down near the event horizon and it takes an infinite amount of our time for the matter to pass through the event horizon. From the perspective of the matter falling through the event horizon, the passage is uneventful; the matter experiences no sudden changes as it passes through that surface of no return. Instead, the matter continues to accelerate toward the singularity at the center of the black hole to a point of infinite density and infinitely small size. Its approach to the singularity completely destroys the matter's structure. The gravitational tidal forces caused by the differences in gravity at different locations in space tear the matter apart so that it contributes only mass, charge, momentum, and angular momentum to the singularity. The black hole is usual identified with the event horizon rather than the singularity contained inside it. Passage through that event horizon erases any memory of the structure of the matter, leaving only its mass, charge, momentum, and angular momentum observable in the properties of the black hole.
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I'd just like to point out to those who want to engage in the "do black holes exist?" debate, that there are two questions.
1.) Do massive objects exist that collapse beyond their own Schwartzchild radii, thus forming an event horizon?
The answer to this one is very probably yes. Neutron stars maintain hydrostatic equilibrium by the counterbalance of the gravitational inward pressure and the outward pressure of neutron degeneracy. After a certain (debatable, but between 2 and 10 solar masses) point, gravtity overcomes the neutron degeneracy and the star collapses under it's Schwartzchild radius. At this point, it can be called a "black hole" because the escape velocity at the surface of the object, whatever it is, is greater than the speed of light. Unless some process prevents neutron stars from growing by matter accretion past a certain point (and Type Ia supernovae seem to contradict this) or another source of outward pressure than neutron degeneracy exists, this process can and probably has happened.
2.) Once collapsed, do such objects become mathematical singularities within the event horizon?
This is where all of the scary stuff happens, with the math predicting a space coordinate rotating into time, infinite density, etc. The answer to this question is, WE DON'T KNOW, and furthermore, IT DOESN'T MATTER. A black hole will look exactly the same if it is a singularity or just REALLY DENSE.
We talk about black holes as singularities because we don't know of any outward force that can overcome the neutron degeneracy pressure at any point, but once under the event horizon, it doesn't matter if there is a new hydrostatic equilibrium, because it does not effect the rest of the universe.
As for the "evidence" issue, astronomers have observed a handful of massive X-ray sources in tight binary systems (the mass is found by the period of the system) which are really probably black holes. From earth, that is probably the best we can do.
And in case you wonder what my credentials are, I just finished an in-depth course in astrophysics.
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