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Quasar Energy

  1. Jun 28, 2005 #1
    Quasars are known to be the highly luminous neclei at the centre of the galaxy at large red shifts and they emit energy trillions times more than that of sun in form of gamma rays and other radiations.

    May I know what are the other radiations?....What are the various ways in which celestial bodies can emit energy?

    It is believed that the black holes accumulate all the 'dust.gases etc.' around it and this results in enormous amount of energy being emitted because of the high potential energy around the black hole.

    Is it that when the matter like gas, dust etc is being ACCREDITED towards the black hole , due to the large mass of the matter , the potential energy around black hole is changed and this change in potential energy is emitted as gamma rays etc. ? or is it some other mechanism??
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  3. Jun 28, 2005 #2
    well nobody "KNOWS" forsure
    but I think a single unmoving BH is not the answer
    we think most galicys have a massive BH in the center
    maybe the quasar is a result of the formation of this BH
    not by simple matter infall as that is too slow and unlikely to produce the hi-power levels seen in a quazar
    but by several BH all in orbit of each other
    wipping around at high speeds inside the accredited matteral
    each draging a ball or disk of stuff in to the event horizen of the others
    once the massive BH forms the show is over
  4. Jun 28, 2005 #3
    So you mean that Quasars only remain for the time a Black Hole is forming itself?

    Black Hole is not formed by accreting matter like gas, dust from neighbouring parts but it is a result of collapse of star under its own gravity , after which it attracts bits of gas, dust outside it which would hinder the mammoth potential energy of a Black Hole and would result in great energy seen as a Quasar.

  5. Jun 28, 2005 #4


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    A quasar 'exists' as long as the BH is actively accreting mass.

    The evidence supporting the accretion disc concept is the fact the flux from the quasar in different wavelengths varies in time scale according to that wavelength, the shorter the wavelength the shorter the time scale of variation. This is consistent with the idea that at the outer edge of the accretion disc the temperature is lowest and in the inner edge it is highest.

    The light-time diameter of the object determines the time scale that it can be observed to vary.

  6. Jun 29, 2005 #5
    i think maybe quasar is the "balance object" to the BH. it's a harmonic concept of our universe, just like the Ying Yang in Taoism philosophy. tat's because quasar can emit very high energy and in the opposite the BH is absorbing i with an infinte gravitational force. btw, is the quasar also has infinte "emitting force"?
  7. Jun 29, 2005 #6
    i may like to explain a bit further about the Yin Yang philosophy. its basic concept is very simple: everything in the universe must exist in harmonic by having an "balancing object" which has the opposite characters. for example, man & woman, black & white, good & bad, born & death....
  8. Jun 29, 2005 #7
    Ying Yang in Taoism Philosophy?... Black Hole is absorbing the energy with infinite gravitational force?.... never heard gravitational force could 'absorb' energy...

  9. Jun 29, 2005 #8


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    Like 'Action and Reaction being equal and opposite?"

  10. Jun 29, 2005 #9


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    This may be a nice, even very attractive, philosophy.

    However, we are discussing quasars, which we perceive as gamma/X-ray/UV/optical/IR/microwave/radio objects 'on the sky'. Within mainstream astrophysics, these objects are 'explained' as black holes (of mass X) surrounded by accretion disks. The behaviour of the accretion disks is modeled (in mainstream astrophysics) using techniques such as MHD.

    Does this philosophy incorporate the concept of MHD?
  11. Jun 29, 2005 #10
    yes I never said the BHs FORM out of infalling stuff
    only that SUPER MASSIVE BHs form from many smaller ones [that form the normal way [ ie supernovi ]
    + the stuff they get by moving in orbit around other BHs feeding each other on the disks they each have
    the super massive BHs that form the center of most galixcys
    started as smaller stellar BHs and need to grow to super massive size
    during this growth phase we see quasars
    and as far as I know
    no galixcys have been seen with a old galixcy + and old quasar
    all are young and at some point the quasars STOPS
    no galixcy has been seen with multi BHs in the center
    or multi quasars in one galixcy
    if the super massive BH is coexistant with the quasar then how did it get to that size
    and why does it turn off
    and why does only one BH grow to super massive size in each galixcy
    my idea explains that
    poke at it all you want
    just donot try to point out errors that are not part of the basic IDEA
  12. Jun 30, 2005 #11
    That means the Quasars remain during the period the black holes are accreting the matter around them and further increasing their strength, and during this , the massive Gravitational Potential Energy near a black hole is changing drastically , leading to advent of prodigous amounts of energy seen as a 'Quasar'.

    That would mean that Quasar does not have a 'material-presence' but rather is seen as 'radiation being emitted due to acretion taking place due to the black hole behind it
    , it is more of a 'form of energy' as a result of activities of black hole.right?

  13. Jan 10, 2008 #12
    I've scanned some literature and journal, but could not find a description of quasar component and how the energy produce from it's core. Can someone please explain or point me to an accessible paper? Thanks before.
  14. Jan 11, 2008 #13


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    Infinite gravity is an interesting concept. I think it would require infinite mass. It does not require much mass to create a bright light at the e=mc^2 exchange rate. It is also possible inordinately bright quasars are favorably tilted in our direction.
  15. Jan 11, 2008 #14
    So if the piece of candy you were eating suddenly turned into a quasar, would the people in China know? :tongue2:
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