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Black Hole Factory

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Found this article: Despite Rumors, Black Hole Factory Will Not Destroy Earth

Sounds like someone's trying to find evidence supporting string theory. If string theory is groundless, as Stephen says, then these efforts will be doomed to failure, no? Also, since the article implies that black holes will form only if the "extra dimensions" exist, no black holes should be observed anyway. In addition, since black holes appear to violate the law of identity, even fewer than no :blink: black holes should be observed. Right?

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Found this article: Despite Rumors, Black Hole Factory Will Not Destroy Earth

Sounds like someone's trying to find evidence supporting string theory. If string theory is groundless, as Stephen says, then these efforts will be doomed to failure, no?

The theory is doomed, but the efforts are not. The experimental facility mentioned in the article, the Large Hadron Collider (LHC) at CERN, will operate at an unprecedented energy scale, providing a wealth of evidence for particle physics when completed.

Also, since the article implies that black holes will form only if the "extra dimensions" exist, no black holes should be observed anyway.

Black holes cannnot exist, as currently defined, but there is lots of "observational" evidence taken for their existence now. So, don't be too surprised if "evidence" for extra dimensions is likewise found. When it comes to these esoteric theories, it is not the factual evidence that I dispute, but the interpretation of that evidence. The article claims that if the LHC creates these tiny black holes, it will "prove that extra dimensions of the universe exist." So here we have (among other problems) a double interpretation problem, where evidence for black holes is then itself taken as evidence for extra dimensions. It boggles the mind, but the actual experimental data from LHC might be of enormous value, at least to a proper theory.

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The theory is doomed, but the efforts are not. The experimental facility mentioned in the article, the Large Hadron Collider (LHC) at CERN, will operate at an unprecedented energy scale, providing a wealth of evidence for particle physics when completed.
Absolutely. I didn't mean to make light of the project, just some of the implications of the article. :blink:

I am, however, looking forward to any advances resulting from new discoveries made with the LHC, for those "destroy the earth" possibilities. "Become an Evil Overlord" is on my to-do list, you see.

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Just as a random comment to point out, if black holes did/do exist, and this factory could make them:

A big misconception people have is that a black-hole would be some devestating force in the Universe, sucking up everything around it like a giant cosmic Hoover-vacuum.

But actually, from a distance, a black-hole's gravitational pull is going to be identical to that of the original body that collapsed to form it, because a black-hole is only going to have as much mass as the object it came from.

So if, by some bizarre method found only in science-fiction, a mad-scientist turned Jupiter into a Black-Hole, our solar-system wouldn't spiral into oblivion like water down a drain. Things would probably continue as normal, just Jupiter wouldn't be quite as exciting to look at anymore.

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So if, by some bizarre method found only in science-fiction, a mad-scientist turned Jupiter into a Black-Hole, our solar-system wouldn't spiral into oblivion like water down a drain. Things would probably continue as normal, just Jupiter wouldn't be quite as exciting to look at anymore.

That depends on what you mean by "normal." The tidal forces of a black hole with the mass of Jupiter (assuming your "mad-scientist" found such a method) would be much stronger at the event horizon than the tidal forces near the surface of Jupiter. Note that Jupiter's tidal forces broke up comet Shoemaker-Levy 9 into many parts as it approached the planet, and the tidal forces of the black hole would have been much more substantial as the comet approached the event horizon.

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That depends on what you mean by "normal." The tidal forces of a black hole with the mass of Jupiter (assuming your "mad-scientist" found such a method) would be much stronger at the event horizon than the tidal forces near the surface of Jupiter. Note that Jupiter's tidal forces broke up comet Shoemaker-Levy 9 into many parts as it approached the planet, and the tidal forces of the black hole would have been much more substantial as the comet approached the event horizon.

That is why I said "from a distance" in the beginning of the post.

But yes, needless to say, anything near the surface of Jupiter when this happened would have a particularly bad day!

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"The theory is doomed, but the efforts are not. The experimental facility mentioned in the article, the Large Hadron Collider (LHC) at CERN, will operate at an unprecedented energy scale, providing a wealth of evidence for particle physics when completed."

Doesn't that assume that we really understand fundamental particles and that the model we are using for them is correct? If we don't, if our basic premises are wrong, will we not then draw completely invalid conclusions?

I don't think we, qua establishment, have it right. I think our understanding of the effect of 'gravity' is wrong, our understanding of atomic structure is wrong and our understanding of time as well as the concept of 'Now' is wrong too.

We cannot explain where the energy comes from that keeps planets in orbit (if indeed energy is being expended), how a fridge magnet stays in place without running out of energy, or even how freezing water breaks pipes when it 'loses' energy although a great deal of energy is required to break the pipe. In short, I think we've got something fundamental very much wrong.

Cheers

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The theory is doomed, but the efforts are not. The experimental facility mentioned in the article, the Large Hadron Collider (LHC) at CERN, will operate at an unprecedented energy scale, providing a wealth of evidence for particle physics when completed.

Doesn't that assume that we really understand fundamental particles and that the model we are using for them is correct?

No. What I said does not assume that the standard model is correct.

If we don't, if our basic premises are wrong, will we not then draw completely invalid conclusions?

Yes, of course.

I don't think we, qua establishment, have it right. I think our understanding of the effect of 'gravity' is wrong ...

In what way is "our understanding of the effect of 'gravity' ... wrong?" Apples usually fall dowards to Earth, rather than upwards to the sky. Do I understand that wrongly?

... our understanding of atomic structure is wrong and our understanding of time as well as the concept of 'Now' is wrong too.

If you have studied relativity, in what way do you think its understanding of time and the concept of "now" is wrong?

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------

or even how freezing water breaks pipes when it 'loses' energy although a great deal of energy is required to break the pipe. -------

Cheers

It is not the energy loss from the freezing water in the pipe that causes the pipe to burst.

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It is not the energy loss from the freezing water in the pipe that causes the pipe to burst.

Correct, it would be work done by the crystallization of the water as it cooled, which would probably be the electron-structure's fault.

This is the part of an undergraduate classical-Physics course where the Professor sticks both arms in the air, waves his hands and says "...for purely Quantum-Mechanical reasons!".

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I'd like to hear more about Black Holes. Can someone describe what ever they know about them that does not violate the law of identity?

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I'd like to hear more about Black Holes. Can someone describe what ever they know about them that does not violate the law of identity?

Every planet/star/etc has an escape velocity. If you cram the object so it gets smaller in volume and more dense in mass per volume, the escape velocity goes up. If you go far enough the escape velocity will exceed the speed of light in vacuum, and you will have a black hole. There's nothing wrong with this with respect to the law of identity.

What's inside the black hole, or what happens when you pass through one? Some of the hypothesized details certainly do violate metaphysics (singularities, going back in time, going to a different universe, etc.)

Regardless, the basic idea of an object with such strong gravity that light can't escape is a valid one.

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I'd like to hear more about Black Holes. Can someone describe what ever they know about them that does not violate the law of identity?

Every planet/star/etc has an escape velocity. If you cram the object so it gets smaller in volume and more dense in mass per volume, the escape velocity goes up. If you go far enough the escape velocity will exceed the speed of light in vacuum, and you will have a black hole. There's nothing wrong with this with respect to the law of identity.

What's inside the black hole, or what happens when you pass through one? Some of the hypothesized details certainly do violate metaphysics (singularities, going back in time, going to a different universe, etc.)

Regardless, the basic idea of an object with such strong gravity that light can't escape is a valid one.

From the Wiki article on black holes:

"Objects whose gravity field is too strong for light to escape were first considered in the 18th century by John Michell and Pierre-Simon Laplace."

and.

"In 1796, mathematician Pierre-Simon Laplace promoted the same idea in the first and second editions of his book Exposition du système du Monde (it was removed from later editions).[5][6] Such "dark stars" were largely ignored in the nineteenth century, since it was not understood how a massless wave such as light could be influenced by gravity.[7] "

So even within Newtonian gravitation theory, black holes can exist in the mathematical sense.

There is no contradiction with any logical principle and the NASA reference provides -empirical- evidence for black holes. If you have to choose between experimental evidence and (so-called) a priori philosophical principles which are so general as to have no scientific application go with the experimental evidence. When fact and theory collide, fact wins.

ruveyn

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I'd like to hear more about Black Holes. Can someone describe what ever they know about them that does not violate the law of identity?

Every planet/star/etc has an escape velocity. If you cram the object so it gets smaller in volume and more dense in mass per volume, the escape velocity goes up. If you go far enough the escape velocity will exceed the speed of light in vacuum, and you will have a black hole. There's nothing wrong with this with respect to the law of identity.

What's inside the black hole, or what happens when you pass through one? Some of the hypothesized details certainly do violate metaphysics (singularities, going back in time, going to a different universe, etc.)

Regardless, the basic idea of an object with such strong gravity that light can't escape is a valid one.

That's really interesting and exactly what I was looking for. Thank you Carlos.

Is there any known information as to how long a black hole exists?

Does it just accumulate stuff that comes into its gravitational pull until it has enough stuff to form a planet or star?

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Is there any known information as to how long a black hole exists?

I don't think anybody knows. It's a subject many theoretical physicists have explored, but I don't have the expertise to discern the legitimate scientific inquiry from the rationalist fluff. It is very interesting though. I think Hawking once thought that a black hole could evaporate and explode over time...

Black holes are probably at the center of many galaxies, and their strong gravity probably influences many important processes on the galaxy scale, so understanding them is important.

Does it just accumulate stuff that comes into its gravitational pull until it has enough stuff to form a planet or star?

Presumably it began as a star, and once the star exhausted its fuel it no longer could generate sufficient outwards pressure against the colossal inwards gravitational pressure. At that point the star leaves the main sequence and forms a dense, white dwarf. If the star were heavier from the start it could collapse further to form a black hole.

To understand why it collapses you have to understand that by volume the majority of matter is empty space, and the apparent solidness we experience when we touch objects like a wooden chair comes from the underlying fields which produce a balance of attraction and repulsion between the subatomic particles making up that chair. Two neighboring atoms in that chair are attracted by electrostatic forces to form a molecular bond, but if you were to squeeze those two atoms together in a vice eventually there would be a great repulsion between the two atoms, coming from the electrostatic repulsion of the positively charged nuclei. Squeeze hard enough and you can overcome this barrier and short-range attractive nuclear forces will bind the nuclei together, causing a nuclear reaction and releasing a lot of energy. Stars do this with gravity. They start with mostly hydrogen and helium, and go through processes of fusing those nuclei to make heavier nuclei. Through several life cycles they "burn" through the periodic table, making heavier and heavier elements. (this is probably, btw, the source of the heavier elements in our universe). After 57-Fe (an isotope of iron) this process no longer releases energy, because 57-Fe has the highest binding energy per nucleon. At this point the energy released from nuclear reactions cannot sustain the star against the inwards gravitational pressure.

Besides electrostatic repulsion, another important kind of repulsive "force" is degeneracy pressure coming from the exclusion principle. Quantum Mechanics says that no two fermions (electrons are fermions, for example) may occupy the same quantum state. As a star is dying and being collapsed and squeezed tighter and tighter, it is theorized you reach a point where it is supported purely by degeneracy pressure. If the gravity overcomes this, it is theorized that the electrons and protons can combine to form neutrons, and a neutron star is formed. As neutrons are fermions, the star is now supported by neutron degeneracy pressure. If the gravity overcomes this, further collapse can happen and you'll probably get a black hole.

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Regardless, the basic idea of an object with such strong gravity that light can't escape is a valid one.

Gravity faster than light?

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Regardless, the basic idea of an object with such strong gravity that light can't escape is a valid one.

Gravity faster than light?

From the Wiki article on the speed of gravity:

"In September 2002, Sergei Kopeikin and Edward Fomalont announced that they had made an indirect measurement of the speed of gravity, using their data from VLBI measurement of the retarded position of Jupiter on its orbit during Jupiter's transit across the line-of-sight of the bright radio source quasar QSO J0842+1835. Kopeikin and Fomalont concluded that the speed of gravity is between 0.8 and 1.2 times the speed of light, which would be fully consistent with the theoretical prediction of general relativity that the speed of gravity is exactly the same as the speed of light.[18"

The entire article is at: http://en.wikipedia.org/wiki/Speed_of_gravity

ruveyn

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