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Black holes

  • 18-07-2010 1:58pm
    #1
    Closed Accounts Posts: 135 ✭✭


    What is your theory of black holes? I do not believe they are holes at all. They are gravitational balls, like huge gas planets. All the black matter the scientist say is out there, is gravity, and a black hole is simply a huge mass of this. Gravity is heavier than light and attracts itself slowly. Gravity balls also trap any lighter particle which happens to go too near to it, and the lighter particle cannot escape, (light), giving us a view of a hole. Eventually the gravity ball will have trapped so much light that it will no longer have the mass to contain it, and then a clataclismic explosion will happen. We on Earth will probably never see this event happen...and would probably not want to.

    Perhaps this was the cause of the big bang.


Comments

  • Closed Accounts Posts: 33,733 ✭✭✭✭Myrddin


    I dont think its a hole in a conventional sense, it's a three dimensional sphere after all. Almost infinite mass bends space time so much that space itself is warped in on itself.


  • Registered Users, Registered Users 2 Posts: 1,576 ✭✭✭Improbable


    Most of my knowledge of black holes come from popular science rather than hard physics. The way I understand it, the mass of the singularity determines the radius of the event horizon, the point at which the warping of spacetime or space (i'm not sure which) is great enough to prevent anything from escaping. However the creation of something like paired particles and anti-particles at the edge of the event horizon annihilate and result in the release of hawking radiation which could possibly cause the evaporation of black holes over time.


  • Registered Users, Registered Users 2 Posts: 2,214 ✭✭✭wylo


    Improbable wrote: »
    However the creation of something like paired particles and anti-particles at the edge of the event horizon annihilate and result in the release of hawking radiation which could possibly cause the evaporation of black holes over time.
    Could you elaborate more here, im not too sure what you mean, just learning about this stuff myself.


  • Registered Users, Registered Users 2 Posts: 1,576 ✭✭✭Improbable


    wylo wrote: »
    Could you elaborate more here, im not too sure what you mean, just learning about this stuff myself.

    Ok, that was slightly wrong. What I think happens is that for some reason that i'm not too sure about, particle, anti-particle pairs are produced at the event horizon. Before they can annihilate, one particle falls beyond the event horizon and one escapes it. The one that escapes is theorized to have positive energy and the one that falls in has negative energy, thus decreasing the energy (i.e. mass) of the black hole.


  • Registered Users, Registered Users 2 Posts: 8,551 ✭✭✭Rubecula


    When matter falls into a black hole. (Or energy for that matter as I believe they are just two forms of the same thing) Where does it go? Is it destroyed as most suggest, or does it go into a white hole and emerge elsewhere.

    Was the big bang a White hole formed by a black hole in another universe?

    If so are Black holes the source of new universes outside our ken?

    Another point is, a black hole can only "swallow" so much at once, too much and it produces vast "beams" of highly energetic energy and matter.

    A bit like lighthouse beams.


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  • Registered Users, Registered Users 2 Posts: 1,576 ✭✭✭Improbable


    Rubecula wrote: »
    Another point is, a black hole can only "swallow" so much at once, too much and it produces vast "beams" of highly energetic energy and matter.

    A bit like lighthouse beams.

    Say what now?


  • Registered Users, Registered Users 2 Posts: 2,214 ✭✭✭wylo


    I think their talking about quasars but i dont think thats the cause of them tbh.


  • Registered Users, Registered Users 2 Posts: 144 ✭✭gentillabdulla


    wylo wrote: »
    I think their talking about quasars but i dont think thats the cause of them tbh.

    Quasars, if I am not mistaken, are caused by super massive black holes making the area near the center of a galaxy, I think it was called the galactic nucleus, very dense and shooting matter out of it through there jets.

    Making everything really really bright.


  • Registered Users, Registered Users 2 Posts: 144 ✭✭gentillabdulla


    Rubecula wrote: »
    When matter falls into a black hole. (Or energy for that matter as I believe they are just two forms of the same thing) Where does it go? Is it destroyed as most suggest, or does it go into a white hole and emerge elsewhere.

    Was the big bang a White hole formed by a black hole in another universe?

    If so are Black holes the source of new universes outside our ken?

    Another point is, a black hole can only "swallow" so much at once, too much and it produces vast "beams" of highly energetic energy and matter.

    A bit like lighthouse beams.
    It goes straight towards the singularity after it passes the event horizon, which is the horizon that if you pass you cannot get out, and becomes compressed infinitely.


    Well the black holes can be thought of as a bucket.

    While there is no limiting factor to how much it can take over a year there is a limiting factor to how much it can all at once.

    Then the matter it doesn't take in is spewed out in massive jets. The speed of these jets is due to the gravitational assist that occurs when the matter moves away from the black hole.

    But all this happens outside the event horizon.


  • Registered Users, Registered Users 2 Posts: 144 ✭✭gentillabdulla


    furerer wrote: »
    What is your theory of black holes? I do not believe they are holes at all. They are gravitational balls, like huge gas planets. All the black matter the scientist say is out there, is gravity, and a black hole is simply a huge mass of this. Gravity is heavier than light and attracts itself slowly. Gravity balls also trap any lighter particle which happens to go too near to it, and the lighter particle cannot escape, (light), giving us a view of a hole. Eventually the gravity ball will have trapped so much light that it will no longer have the mass to contain it, and then a clataclismic explosion will happen. We on Earth will probably never see this event happen...and would probably not want to.

    Perhaps this was the cause of the big bang.

    Black holes can be thought of as spheres that have so much gravity that they tear the spacetime fabric.

    Dark matter is actually just matter that can only be seen through its gravitational effects.

    Gravity itself is just mass and energy bending space and time, it doesn't weigh anything because weight is just the downward pull that mass has in a gravitational field.

    There is a theory that the big bang was just a black hole that exploded due to not having any more spacetime to warp.

    It is because spacetime is what causes the infinite energy density in a black hole so when the black hole suck that up all the way it explodes.(Again due to not having gravity because gravity is a depression in spacetime.)


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  • Registered Users, Registered Users 2 Posts: 144 ✭✭gentillabdulla


    wylo wrote: »
    Could you elaborate more here, im not too sure what you mean, just learning about this stuff myself.


    Its just black body radiation applied to the event horizon of a black hole.

    Then Hawking found that a black hole cannot have a temperature of absolute zero so that means it must radiate.

    Its radiation is proportional to the size of the event horizon because the event horizon determines how much gravity it has.(And mass)

    And gravity is the thing that causes the temperature to be so low in the first place.


  • Registered Users, Registered Users 2 Posts: 1,976 ✭✭✭Brendog


    Black holes aren't holes at all....This is just the name given to them because they look like a bottomless hole. This is because the gravitational pull is so strong that not even light can escape it.


    In reality if we were to see a black hole from a side view, it would appear as a cone.

    the theory is that this cone shape has an opposite cone parallel to it. Something like you see below....

    wormhole-diagram.jpg


    This referes back to Newtons laws of motions, and his famous quote...

    "Every action has an equal and opposite reaction"


  • Registered Users, Registered Users 2 Posts: 144 ✭✭gentillabdulla


    Brendog wrote: »
    Black holes aren't holes at all....This is just the name given to them because they look like a bottomless hole. This is because the gravitational pull is so strong that not even light can escape it.


    In reality if we were to see a black hole from a side view, it would appear as a cone.

    the theory is that this cone shape has an opposite cone parallel to it. Something like you see below....


    This referes back to Newtons laws of motions, and his famous quote...

    "Every action has an equal and opposite reaction"

    A cone ending in singularity.(Where the tip is the singularity.)

    Yes where a black hole could be a wormhole leading to a parallel universe. Only if there was another black hole in that exact spot in the other universe.

    But anything that tries to pass through one of these wouldn't be able to as it would require a speed faster than light.

    Meaning that the wormhole would close before you could go through it.


  • Registered Users, Registered Users 2 Posts: 1,576 ✭✭✭Improbable


    Brendog wrote: »
    Black holes aren't holes at all....This is just the name given to them because they look like a bottomless hole. This is because the gravitational pull is so strong that not even light can escape it.


    In reality if we were to see a black hole from a side view, it would appear as a cone.

    the theory is that this cone shape has an opposite cone parallel to it. Something like you see below....

    wormhole-diagram.jpg


    This referes back to Newtons laws of motions, and his famous quote...

    "Every action has an equal and opposite reaction"

    Er, there's a difference between a theory of wormholes and a theory of black holes...

    And if the gravity is so strong that light cannot escape it, why does your diagram show that it does just that?


  • Registered Users, Registered Users 2 Posts: 1,576 ✭✭✭Improbable


    Black holes can be thought of as spheres that have so much gravity that they tear the spacetime fabric.

    Dark matter is actually just matter that can only be seen through its gravitational effects.
    First time I've ever heard of that... is there any proof or evidence of that?
    There is a theory that the big bang was just a black hole that exploded due to not having any more spacetime to warp.

    It is because spacetime is what causes the infinite energy density in a black hole so when the black hole suck that up all the way it explodes.(Again due to not having gravity because gravity is a depression in spacetime.)
    Er, even if there was enough mass in the universe to create a large enough black hole to cause an infinite curvature of spacetime, which I don't believe there is, black holes do not "suck up" spacetime.

    A cone ending in singularity.(Where the tip is the singularity.)

    Yes where a black hole could be a wormhole leading to a parallel universe. Only if there was another black hole in that exact spot in the other universe.

    But anything that tries to pass through one of these wouldn't be able to as it would require a speed faster than light.

    Meaning that the wormhole would close before you could go through it.
    What?


  • Registered Users, Registered Users 2 Posts: 144 ✭✭gentillabdulla


    Improbable wrote: »
    First time I've ever heard of that... is there any proof or evidence of that?


    Er, even if there was enough mass in the universe to create a large enough black hole to cause an infinite curvature of spacetime, which I don't believe there is, black holes do not "suck up" spacetime.



    What?
    Yeah there is just look up dark matter it can only be shown by its effects on light.

    Because Dark matter has gravity if it had any electrical properties then it would have been observed by now.

    Actually a black hole does "suck up" spacetime.

    It is plainly seen in how matter and energy bend spacetime.
    The more matter is compact then the more spacetime is warped outside the object.

    With enough warp the fabric rips but spacetime continues to be warped into the object due to matter and energy bending space and time.

    Most people believe that the big bang was really just a singularity with all the mass of the universe. That exploded due to there not being anymore spacetime.

    I meant that a black hole could be a wormhole to another universe as long as another black hole is stationed at the exact same spot.

    Now there are some drawbacks as I mentioned.

    You, or anything else, cannot move through the wormhole because any information exchanged between the universe would make the wormhole collapse.

    This means you would have to go through wormhole at faster than light speeds.


  • Registered Users, Registered Users 2 Posts: 1,576 ✭✭✭Improbable


    Yeah there is just look up dark matter it can only be shown by its effects on light.

    Because Dark matter has gravity if it had any electrical properties then it would have been observed by now.

    Actually a black hole does "suck up" spacetime.

    It is plainly seen in how matter and energy bend spacetime.
    The more matter is compact then the more spacetime is warped outside the object.

    With enough warp the fabric rips but spacetime continues to be warped into the object due to matter and energy bending space and time.

    Most people believe that the big bang was really just a singularity with all the mass of the universe. That exploded due to there not being anymore spacetime.

    Again, you're offering no proof or evidence of that. How much mass would be required to create a singularity that could cause an infinite curvature of all spacetime?


  • Registered Users, Registered Users 2 Posts: 144 ✭✭gentillabdulla


    Improbable wrote: »
    Again, you're offering no proof or evidence of that. How much mass would be required to create a singularity that could cause an infinite curvature of all spacetime?

    You are assuming that the black hole didn't collect the mass in the first place.

    It could have been a merger with other black holes that finally turned into one ultra massive black hole.

    http://physicsworld.com/cws/article/news/23838
    This mysterious form of matter does not emit or absorb electromagnetic radiation -- hence the name "dark" -- and can only be detected by its gravitational influence on ordinary matter. According to the standard model of cosmology, the universe is thought to contain about 5% ordinary matter, 25% dark matter and 70% dark energy -- the nature of which is unknown.


  • Registered Users, Registered Users 2 Posts: 1,576 ✭✭✭Improbable


    Yeah there is just look up dark matter it can only be shown by its effects on light.

    And now you just contradicted that...


  • Registered Users, Registered Users 2 Posts: 144 ✭✭gentillabdulla


    Improbable wrote: »
    And now you just contradicted that...
    How so?


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  • Registered Users, Registered Users 2 Posts: 1,576 ✭✭✭Improbable


    This mysterious form of matter does not emit or absorb electromagnetic radiation -- hence the name "dark" -- and can only be detected by its gravitational influence on ordinary matter.


  • Registered Users, Registered Users 2 Posts: 144 ✭✭gentillabdulla


    Improbable wrote: »
    This mysterious form of matter does not emit or absorb electromagnetic radiation -- hence the name "dark" -- and can only be detected by its gravitational influence on ordinary matter.

    Yeah it doesn't emit or absorb electromagnetic radiation it just has gravity.

    It can only be shown by the bend it brings about on electromagnetic radiation.

    Not absorbing or emitting just bending through gravity.


  • Registered Users, Registered Users 2 Posts: 1,576 ✭✭✭Improbable


    If they have that amount of gravity in those quantities, could they not be observed through their gravitational effects on ordinary matter rather than just on light? I think its a bit misleading to say they can only be observed through its effects on light.

    And what does this have to do with a theory about black holes?

    And you still haven't stated how much mass would be required to cause an infinite curvature of all spacetime.


  • Registered Users, Registered Users 2 Posts: 144 ✭✭gentillabdulla


    Improbable wrote: »
    If they have that amount of gravity in those quantities, could they not be observed through their gravitational effects on ordinary matter rather than just on light? I think its a bit misleading to say they can only be observed through its effects on light.

    And what does this have to do with a theory about black holes?

    And you still haven't stated how much mass would be required to cause an infinite curvature of all spacetime.

    Light is ordinary matter.

    I don't know why they wouldn't use light.


    It was mentioned in the original post or op if you will.

    When you say infinite curvature what do you really mean?

    Is it infinite curvature in the accretion disk, outside the event horizon, or near the cauchy horizon, or even the singularity?(Which always has infinite curvature because it is the center of a black hole.)


  • Registered Users, Registered Users 2 Posts: 1,576 ✭✭✭Improbable


    Light is ordinary matter.

    I don't know why they wouldn't use light.
    What I'm saying is that since it has gravitational properties, it can be observed through its effects on matter other than light, whereas you stated:
    Yeah there is just look up dark matter it can only be shown by its effects on light.

    When you say infinite curvature what do you really mean?

    Is it infinite curvature in the accretion disk, outside the event horizon, or near the cauchy horizon, or even the singularity?(Which always has infinite curvature because it is the center of a black hole.)

    You were the one that said after there was no spacetime left that we would get another "big bang". So you tell me...


  • Registered Users, Registered Users 2 Posts: 144 ✭✭gentillabdulla


    Improbable wrote: »
    What I'm saying is that since it has gravitational properties, it can be observed through its effects on matter other than light, whereas you stated:

    You were the one that said after there was no spacetime left that we would get another "big bang". So you tell me...

    Do all objects emit light? Yes if they didn't then they would be Blackbodies.

    Can dark matter be shown by its effects on visible matter, other than light? I wouldn't think so it would need a significant amount of dark matter to do so.

    (Astronomy is not really my subject of expertise so I still may be wrong.)

    Well I will insert all the mass in the universe, theoretical included, into the schwarzschild equation.

    That mass, compressed to the diameter shown, would create an infinite curvature inside as well as outside the event horizon of said black hole.


  • Registered Users, Registered Users 2 Posts: 1,576 ✭✭✭Improbable


    Proof, evidence, reasoning. All you're doing is saying stuff. You're giving no reason why any of it is true.


  • Registered Users, Registered Users 2 Posts: 144 ✭✭gentillabdulla


    Improbable wrote: »
    Proof, evidence, reasoning. All you're doing is saying stuff. You're giving no reason why any of it is true.
    Schwarzschild equation is the equation to find out the schwarzschild radius.(Radius at which any object that goes past its own Schwarzschild radius will form into a black hole.)

    Proof http://scienceworld.wolfram.com/physics/SchwarzschildRadius.html
    The Schwarzschild radius gives the radius at which the Schwarzschild metric becomes singular, and is therefore the "size" of a black hole. It can naively (although incorrectly) be derived by letting the escape velocity of a black hole equal to the speed of light
    simg93.gif

    where G is the gravitational constant, M is the mass of the black hole, and c is the speed of light, giving
    simg97.gif

    Perfect Blackbodies do not emit any electromagnetic radiation

    Proof http://scienceworld.wolfram.com/physics/Blackbody.html
    A hypothetic body that completely absorbs all wavelengths of thermal radiation incident on it. Such bodies do not reflect light, and therefore appear black if their temperatures are low enough so as not to be self-luminous.


  • Registered Users, Registered Users 2 Posts: 1,576 ✭✭✭Improbable


    I know about the Schwarzschild radius and what a blackbody is...

    What is the mass of the universe? would it be enough to do what you say?

    You seem to jump very rapidly from one topic to another without really discussing it.


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  • Moderators, Society & Culture Moderators Posts: 12,853 Mod ✭✭✭✭riffmongous


    Can dark matter be shown by its effects on visible matter, other than light? I wouldn't think so it would need a significant amount of dark matter to do so.
    Dark matter is used as the explanation for why the observed 'rotational curve' (imagine if you divided the galaxy into a series of rings of increasing size, then the curve tells you what speed each ring is moving at) of a galaxy is different to the predicted curve, basically there needs to be more mass there than we can see

    I always thought a blackhole was where the laws of physics broke down, so any theories were purely speculative, fun but with no evidence


  • Closed Accounts Posts: 3,006 ✭✭✭_Tombstone_




  • Registered Users, Registered Users 2 Posts: 8,551 ✭✭✭Rubecula



    Ha ha ha, I love it. :pac:


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