Who come first

Discussion in 'Physics' started by aliashar86, Nov 23, 2006.

  1. aliashar86

    Thread Starter Active Member

    Nov 23, 2006
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    Can any one tell that does light comes first or heat.

    plz giv some detail.
     
  2. beenthere

    Retired Moderator

    Apr 20, 2004
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    Hi,

    You will have to be a great deal more specific about the conditions in your question. There are many cases where light exists without heat, and heat without light.
     
  3. Papabravo

    Expert

    Feb 24, 2006
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    I've never seen any evidence to suggest that laws of Physics have some sort of serial applicability. There are time epochs in the big band theory that suggest different variations of a whole system of laws existed during those epochs. The two present day pieces of evidence for what happened are: cosmic microwave background radiation, and the value of the fine structure constant. The cosmic microwave background radiation which is uniform in every direction suggests that the universe was a much hotter place a long time ago. Changes in the value of the fine structure "constant" over time have many implications for the past behavior of matter, energy, and the four forces.
     
  4. mrmeval

    Distinguished Member

    Jun 30, 2006
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    According to Genesis god came first but that's under dispute. :p
     
  5. aliashar86

    Thread Starter Active Member

    Nov 23, 2006
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    so mr papabravo i will thn consider tht ur view from big bang theory is that heat comes first.
    am i right?
     
  6. aliashar86

    Thread Starter Active Member

    Nov 23, 2006
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    Mr. beenthere plz mention those few cases where light exists without heat and vice versa
     
  7. Papabravo

    Expert

    Feb 24, 2006
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    No I don't think I said that. What I said was, there were different epochs and different things happened during those epochs. As I understand things, the laws of Physics in each epoch came into effect simultaneously. Both heat and light are different parts of the electromagnetic spectrum which differ only in frequency and wavelength. As soon as Maxwell's equations are valid for one they must be valid for the other.
     
  8. thingmaker3

    Retired Moderator

    May 16, 2005
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    You indeed didn't say that, Papabravo... Beenthere said that!:)

    I'm not Beenthere either, but here are a couple of examples:

    Flourescent minerals will glow under UV light, but will produce negligable heat.

    Iron heated to a little under 500C will not be glowing yet, but definately will radiate heat into room temperature air. With metals, heat does indeed come before light.

    Cookies fresh from the oven will radiate heat into room temperature air as well - but they don't glow. At least mine don't.
     
  9. Papabravo

    Expert

    Feb 24, 2006
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    Yup. The op posted twice in a row and I grabbed the wrong one. Eh bien! C'est la vie. Honi soit qui mal y pense.
     
  10. Gadget

    Distinguished Member

    Jan 10, 2006
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    What about infrared..??
     
  11. Papabravo

    Expert

    Feb 24, 2006
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    First or Second?
     
  12. EEMajor

    Well-Known Member

    Aug 9, 2006
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    All objects above absolute zero emit infrared light....but again, anything above absolute zero has heat, and all objects we know of are above absolute zero, so....Maybe you can't have one without the other?? Was it the chicken or the egg??
     
  13. Dave

    Retired Moderator

    Nov 17, 2003
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    Absolute zero is a theoretical extreme with complications in the bizarre world of quantum mechanics, therefore it is unlikely ever to (read as never) be achievable in practice. Even the Bose-Einstein Condensate is factionally above absolute zero.

    Oh, and the Chicken came first!

    Dave
     
  14. Papabravo

    Expert

    Feb 24, 2006
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    Actually I think it is the wrong question to ask because it presupposes an answer that either heat or light came first. I'd like to suggest a third possibility that they arrived on the scene at precisely the same instant of time.
     
  15. Dave

    Retired Moderator

    Nov 17, 2003
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    Well if we assume the Big Bang theory to be correct, then surely light only has any meaning one Planck time after the Big Bang, however the Big Bang is assumed to have been a singularity at time 0, of extreme/infinite density and heat. Therefore I propose that heat came before light.

    Dave
     
  16. LINDSROTH@yahoo.com

    New Member

    Nov 13, 2006
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    Dave...Had you given any thought to the definition of light as that which eminates from the atom from the moving of an electron from one level to a higher level and/or the same electron falling back. The movement of the electron is the result of energy being added or taken away and I'm not sure whether the amount of energy would be enough to necessarily create any heat. If what I stated is true and the electron movement can be without heat...then we have light without heat...???LINDSROTH@yahoo.com
     
  17. EEMajor

    Well-Known Member

    Aug 9, 2006
    67
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    You are correct, Dave. I wasn't trying to hint that absolute zero was an achievable temperature, rather that nothing was at absolute zero, therefore everything has both heat and light.

    Thanks for the clarification!:)
     
  18. Dave

    Retired Moderator

    Nov 17, 2003
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    Well a photon doesn't intrinsically have heat, but energy which can be transfered to produce heat. As an example, think of your porridge in your microwave oven, the microwave has energy which is transfered into lossy materials heating the food volumetrically.

    Its ok, I wasn't challenging your original statement regarding absolute zero, more-so adding some further information.

    As for "everything" having both heat and light, I would certainly agree that that is the case for matter - what about EM waves though?

    Dave
     
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