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Black Holes: Viable Scientific Theory? Or Voo-Doo Science?

  1. May 12, 2003 #1
    [SOLVED] Black Holes: Viable Scientific Theory? Or Voo-Doo Science?

    The "Black Hole" theory has been around for quite a while now and it is amazing that people still talk about it. When it is regarded with even a cursory objectivity it does not satisfy any scientific criteria that would enable it to be regarded seriously. And yet, people, many of them, discuss it in thread after thread and in many media. Why?

    When you analyze the theory you are struck by the incongruity of it. When the "Black Hole" theory states that thousands, and in some cases millions, of star are condensed into a single dense mass that is so small that it is invisible, it is denying that matter has a fundamental size beyond which it cannot be compressed. If there is no fundamental size to matter, then there can be no construction.
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  3. May 12, 2003 #2
    It's no worse in that regard

    than the Dark Matter/Missing Mass hypothesis. First proposed in the 50's by an observational astronomer to explain galactic rotation, no one seems to have seriously questioned it's validity even though tens of millions of dollars and much telescope time has been spent looking for it without success. In the meantime we've learned much about the variety of particles and forces at work in the world, but apparently not enough for people to see the possibility of other explainations than Dark Matter. A very simple statistical analyses will show that it is a very unlikely candidate (one might say the odds are astronomical) for galactic motion.

    I would gladly nominate for the Nobel Prize the first person to write a paper refuting the Dark Matter Hypothesis. They would be doing Astrophysics a great service.
  4. May 12, 2003 #3


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    The possibility of black holes is a simple deduction from two facts:

    (a) Light has finite speed
    (b) Light is affected by gravity

    therefore one is naturally led to wonder if gravity can be sufficiently strong to keep light from getting away.

    Mathematically, general relativity does not deny this possibility; there are solutions to the gravitational field equations that permit sufficiently dense masses to create a region of space-time from which light cannot escape.

    They were regarded as a mathematical curiosity until evidence was discovered that they are real; for example, astronomers have found stars that have an orbit characteristic of a binary star system, but with no directly detectable companion star. Even better, such systems have been found where gas is being sucked away from the visible star to the spot where the companion should be, but no companion is detectable, and the swirling of the gas (and emitted x-ray jets) behave in a fashion consistent with that predicted of a black hole.

    That is only for so-called supermassive black holes, the kind thought to be in the centers of some galaxies. Some of these supermassive black holes are thought to have billions of solar masses. Behavior of the type seen at http://csep10.phys.utk.edu/astr162/lect/active/smblack.html that is exactly what one would expect from such a thing.

    However, many "observed" black holes are far more modest, such as the single-star black holes in the aforementioned binary systems.

    General Relativity does not predict that black holes even need stellar quantities of mass; it permits objects of any mass to form a black hole, if it can be packed densely enough.

    The truth of your assertion that matter does indeed have a fundamental size beyond which it cannot be compressed is very much in doubt, but that is merely a side issue because:

    "Black hole theory" does not deny your assertion. It only says that matter can be compressed a sufficient amount to prevent light from escaping. For stellar sized objects, the compression required for a black hole is well within the limits of general relativity's applicability.
    Last edited: May 12, 2003
  5. May 12, 2003 #4


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    Re: It's no worse in that regard

    Maybe you guys haven't been paying attention, but the Hubble has found a number of objects which can be nothing but black holes.

    I won't go into it now, but Hurkyl did a good job.
  6. May 13, 2003 #5
    Hurkly did a good job, but there is somehting that John is missunderstanding, the mass isn't compressed into a point so small that it can't be seen, infact naked singularities have been mathmaticlay proven, but not observed, the size of a singularity can be very very large. Another point is that Hawking radiation can be observed, and a black hole is the only way to creat Hawking radiation. I think were you went wrong John was looking to much at the language of ways that people attempted to explain black holes, objects such as these are hard to put into words, you need to look at the numbers to understand them.
  7. May 13, 2003 #6
    I agree with ALL the comments. Without being mean towards the author John, I find alot of instances here, and elsewhere, where people assert the validity/existance of something that has already been proven in many ways. Or better yet I should say they assume there's no evidence yet, when in fact there has been for some time.

    Normally I'd first ask "Is anyone up to date on the current evidence on -----?"

    One could blame the person for not doing research, which is what I usually do. However, There has yet to be properly funded attempts to truly unite the scientific community and keep them up to date on knowledge. It's sad but true.

    I recently heard of a web database project bringing alot of "journal members only" material to the general public, particularly to people like me, college students wanting to keep up. Does anyone know the URL and name of that? Thanks all
  8. May 13, 2003 #7


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  9. May 13, 2003 #8


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    If you're saying that essentially people simply don't understand what a black hole is, I agree. Most people have the idea that black holes "suck everything in" and allow nothing to escape (not even light), and are therefore completely undetectable.

    But I don't think you need any math to understand why they are detectable - Stephen Hawkings' description in "A Brief History of Time" makes good sense to me. Their gravitational attraction alone is enough to validate the theory.
  10. May 13, 2003 #9
    There have been many thread which deal with the fantasy aspects of "Black Holes", so many that simply stating you believe in "Black Holes" because someone else said they exist has become a common defense. There is no good reason to go over that endless succession of repetitive platitudes. To engage in a discussion for the further advancement of your understanding, it is necessary to do the critical thinking for yourself. You can take the approach of someone like my friend from Sciforums, "Q", and deride discussion that doesn't conform to personal belief (at least that's mostly what "Q" contributed to Sciforums and I'd wager a similar contribution is "Q's" input to this forum) or you can engage in a discussion in which there is potential for a clearer understanding of reality.

    My intent in starting this thread was not to partake in a joust, or to have to read inanities, nor to see some mensa weenie attempt to showcase their wit. The idea is to have an intelligent conversation that is both friendly and rewarding. To deviate from the logical progression that the discussion should take is, to me, a waste of time. So why bother?

    To get to the thread topic, I'll make the observation that nothing can be constructed out of nothing. This clearly means that whatever the smallest particle of matter is, it definately has mass. If it has mass, it must occupy space. If it occupies space, then there is a compression limit beyond which it cannot be reduced. That is a simple but fundamental observation that precludes the possibility of infinite density.

    No particle of matter can occupy two positions simultaneously. Therefore, if matter is condensed it must build on the heap of the matter that is at the bottom of the pile. If matter was to condense in such a fashion that it packed together so tightly that there were no spaces left between the particles of matter, then it could have no motion. Each individual particle would have to come to a complete stop because it would be completely encircled by other particles that would be just as tightly squeezed as all the other particles. If there is no motion, then there is no gravity. Gravity is not some force which has no source. It, the same as any other force, is dependant on the interaction between bodies.
  11. May 13, 2003 #10
    A very good point. Too many people on these boards forget they're trying to discuss something rather that prove they are correct.

    mmm hm.

    First, not all particles have mass. Photons, for example, have zero rest mass. That is beside the point, however, since black holes do have mass. However, you are incorrect in stating that something with mass need occupy space. That hasn't been proven, although string theory is pointing us in that direction. Still, a black hole is not said to be infinitely small or infinitely dense. That is the traditional view of the singularity, true, but not of the black hole itself. The traditional concept of the singularity, too, has little bearing on modern theory.

    Gravity is the curvature of spacetime, which does not require motion.
  12. May 13, 2003 #11


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    Ever heard of Quantum Mechanics ? :wink:
  13. May 13, 2003 #12


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    You can take the approach of someone like my friend from Sciforums, "Q", and deride discussion that doesn't conform to personal belief (at least that's mostly what "Q" contributed to Sciforums and I'd wager a similar contribution is "Q's" input to this forum)

    One only need read the thread I linked above to decide for themselves whose is a “personal belief,’” right John?

    or you can engage in a discussion in which there is potential for a clearer understanding of reality.

    I’m looking forward to once again hearing your version of reality. Have you dreamed up anymore fantasies since we last heard from you?
  14. May 13, 2003 #13


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    Who said black holes had infinite density? Black holes simply require a radius at which V^2/ r = force of gravity requires a v greater than c, and r being larger than the radius of the object, hence implying that any light at a certain distance cannot form a stable orbit and must fall inwards. If you do the maths, you would find that the density required for such an occurance is far from infinite. The existence of a singularity within the blackhole, where the mass has collapsed to one point, is as a concept distinct to that of the black hole itself.
  15. May 13, 2003 #14


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    Allow me to be frank; nearly every time I've heard someone suggest to me that I do some critical thinking, the person who suggested it meant only that I apply critical thinking to my own beliefs, but that I should accept his assertions.

    True critical thinking goes both ways; not only should you question your own beliefs, but you should also question what others would have you believe. (the latter is arguably far more important than the former)

    When I see assertions that contardict what I think to be true, I do two things: I try to estimate the validity of the assertions, and I try to see how those assertions relate to what I think. When I try to convince someone else of something, I apply the same criterion to my own statements.

    At the moment, your points fail to meet both of my criteria. You've made many assertions which I have no reason to believe, and you haven't even connected your assertions to black holes.

    Among the other problems with your assertions, consider this: in classical mechanics (ala Newton gravitation) as matter collects together, the amount of mass in the object grows cubically in relation to the radius of the object, but the strength of surface gravity only dies off quadratically with radius. Even if you fixed the density of the object to be a constant, you could still make its surface gravity as strong as you like by simply throwing more mass onto the object.
  16. May 13, 2003 #15


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    I would certainly agree that most people's understanding of black holes comes from fantasy and science fiction and thats why people get the science wrong - sorry to say, but YOU fall into that category. You really just need to read up on what black holes really are and how they work. And while you're at it, you seem to have trouble with gravity:
    Einstein's relativity states that an object does indeed have a gravitational affect on the universe itself - no other object is needed. And on massless things like light, it has an effect without exerting a force.

    Since the black hole prediction was derived from Relativity, you must first understand Relativity before you can understand black holes.

    I highly recommend "A Brief History of Time." Its an excellent starting point for learning about the structure of the universe and the rules that govern it.
    Last edited: May 13, 2003
  17. May 14, 2003 #16
    Writing a mathematical formula onto paper and then saying that formula is proof for a theory of "Black Holes" is not science. A mathematical formula can be written about anything and having a mathematical formula for the physical existence of a phenomena that is itself theoretical makes the mathematical formula theoretical. To claim the theoretical mathematical formula proves the theoretical "Black Hole" theory is without justification and is itself idle speculation that adds nothing to understanding.

    Claiming that gravity is the curvature of spacetime is another example of reiterating tired cliches. The purpose of this thread is to examine the reality of "Black Holes", or the more likely impossibility of their existence. Whatever your view of spacial construction, you must have a basic understanding of matter in order to appreciate system construction. A system can only be the sum of it's parts. Gravity, the same as any force, must be the product of physical interaction at some point. It is not a magical force that "just exists". Gravity is the product of bodies in motion. There is no evidence in physics which suggests that there are physical bodies at rest.

    All energy, whether it is percieved as having a physical form or whether it is perceived as a force, has mass. It must have mass for it to exist. Because we cannot differentiate between particle and force is no reason to suspect that force is anything other than the interaction of tiny particles at some level. Because the tiny particles of force behave in waves is a sure indication of their existence, since they have direct affect on other particles of their kind to ensure the extension of whatever field they are a part of. The sum total of our knowledge about force is from observance of effect. We know nothing of the construction of force if we are required to state it's physical construction. To state that we know what force is made of because we observe it's effects is a belief system and not a knowledge system.
  18. May 14, 2003 #17


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    A derivation is not a proof, you're right -- not all solutions to all equations are physical. On the other hand, should black holes actually exist, the mathematics can explain why.
    This claim is actually made by general relativity theory, a hugely successful theory both experimentally and theoretically. It makes a large number of very powerful predictions, most of which have now been verified very precisely.
    Gravity actually seems to be the "product" of mass. No motion need be involved.
    According to even Galiliean relativity, you can always choose a frame of reference so that any body you want is defined to be at rest.
    Energy and mass are equivalent, yes.
    Hmm... it certainly seems we can differentiate particles from forces.

    Crackpot. :)

    - Warren
  19. May 14, 2003 #18


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    Thats not a claim or idle speculation. Thats a PREDICTION - and it has been validated by later observation. No one here said that the mathematical proof is equivalent to physical proof. The physical proof is what validates the theory, not the other way around. There is ample physical proof to validate the theory.

    Again, John, the problem here is that you simply don't understand (and won't listen to explanations of) the existing theories.

    Its so hard to be sure. For now, I'll give him the benefit of the doubt assume he is unable to understand the theories and evidence we are presenting. He just needs to sit down and read up on it.
    Last edited: May 14, 2003
  20. May 14, 2003 #19


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    Its so hard to be sure. For now, I'll give him the benefit of the doubt assume he is unable to understand the theories and evidence we are presenting. He just needs to sit down and read up on it.

    He won’t understand it. Many of us have tried to get John to understand even the very basics of physics to no avail. John has his own brand of science where he makes up terms and theories not based on observation, evidence, or math but from his rather active imagination.

    Of course, I invite all to attempt to reason with John, but if you don’t want to waste a whole lot of time, don’t bother. You can’t get through to him.

    And if you really want to be sure that he is a bona fide crackpot, simply read some of his posts at Sciforums. Some of them are silly in the extreme.

    Ask him about his theory on "Megastars."
  21. May 14, 2003 #20
    Good point to bring up, Q. It's not exactly on topic, but it is interesting astronomy. I'll post a reference to that megastar in a moment, but first I would like to say something about calling people crackpot and other derogatory descriptions. Professional science on this planet is a relatively new endeavor. Lifeforms on this planet have been evolving for perhaps billions of year, yet our organized society has been practicing a recognizable science for a mere few thousand year, if you count the origins of written language as a beginning to perceptional science. If we expect human society to live on this planet for perhaps millions of more year, then the science we practice today will be regarded as an adolescent science by the people who live thousands of year from now. To argue vehemently for one position now, and to exclude varient thought, would be negligent and not scientific. We don't have anywhere near all the answers, which is why things like "Black Holes" and "String Theory" are not proven and remain highly speculative. If you lock yourself into parroting the speculative view, then you can't be thinking critically for yourself. And if you denigrade people who do dare to think critically, and who are unafraid of ridicule when they speak what they believe, then you merely reflect on your own intelligencce by your ill chosen public stance.

    Here's that link to a megastar which Q finds so improbable,


    When you look at this picture you see a bluish galaxy in the top right of the picture and you see a much larger object to the left of it. All, or most, of the other colored objects in the picture are galaxies. The large yellow object in the top left, which looks just like a sun, and is obviously much larger than the largest discernible galaxy, is not displaying any gravitational features that would indicate it was surrounded by orbital bodies. The bodies that appear to be orbiting the megastar are the surrounding galaxies themselves, exemplified by the bluish galaxy which is most recognizable.

    Going through the APOD calendar you can find a number of other examples of objects which appear similar to the megastar in this picture and in each instance they appear to be surrounded by conventional galaxies. Nasa even makes a statement to that effect regarding megastar placement, although they misdiagnose the phenomena as "elliptical galaxies", a non-defining term that is used as a classification for lack of any more clarifying insight.
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