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Does only light have quantized energy.

  1. Oct 5, 2011 #1
    I am reading physics for school and they are talkin about why we don't see the quants of energy in real life because they are too small. But they are realting quants of energy to everyday actions like lifting a stone, like the stone is not continually moving but it's moving in billions of quants. I always tought that only light behaved that way and had certain energy levels and not in between. Someone please help this is bugging me.

    And question two, About the wavelength and frequency of light, Can you add endless amount of energy to one photon so it endlessly increases it's frequency and decreases wavelength. Is there no limit for the frequency of light. I thought i new everything about physics, but now i am learning physics in school and i feel stupid, I had even been developing my own theories.....seems legit.. I don't even understand light.

    Need help.
  2. jcsd
  3. Oct 5, 2011 #2
    The first question is about 'time' or the 'arrow of time' as I see it. And there it depends on what you believe, not 'physics' per se. You can either choose a 'smooth arrow', then you will define what physics you learn and know after that, or you choose a 'quantized arrow', then you will define times arrow after that. In quantum mechanics the later proposition is the most popular, as it fits the way QM seems to 'work', all as I understands it :). Both QM and string theory operate on the assumption that there is discrete 'bits' that when 'puzzled together' creates us.

    For example, a 'wave' can be seen as a smooth phenomena, but a 'particle' might not. And now we will see :)

    As for how much energy a 'photon' can contain? I don't know. It seems to be a function of time, a virtual particle has no limit as I understands it? Then again, we don't measure virtual particles, we measure their secondary effects.

    When we come to 'photons' you have the same problem, some view them as 'discrete bits', other view them as 'wave packets'. Almost as some expression of a continuous wave, although 'chopped up' depending on the way you choose to measure it in time. Think of how a continuous barrage of 'photons' can build up a interference pattern, belonging to the way we would describe a wave to see that one.

    And only a fool would say that he knows it all.
  4. Oct 5, 2011 #3


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    Jarfi, the issue of whether or not spacetime is quantized is one that is still open. It is NOT, however, a matter of personal belief as yoron seems to think. It will be solved one way or the other. What's pretty certain is that in practical terms for everyday stuff, it's irrelevant because if it is quantized the quanta are so small as to be undetectable. It's sort of like that fact that Newton's "law" of gravity is completely wrong but in everyday practical terms for localized (non-relativistic) issues, it gives the right answer to quite a few decimal places.

    Intuitively, it seems to me that neither space nor time should be quantized but I've found that (1) intuition is a TERRIBLE thing to bring to the party when talking about things at the quantum level and (2) the universe doesn't really care what I think.
  5. Oct 5, 2011 #4
    Heh :)
  6. Oct 5, 2011 #5
    So what you are saying is that we don't know weathere everything is quantized or not. And probably never will know, although this is tought in school. And Are they not sure about weather light is quantized or not they just suppose it to make calculations and predictions?.

    BTW the book i am reading is called chemistry: the central sience It's pretty good actually. But they don't really go deep in the physics chapter just give you the basics and a few equations, never answer why the equations are.
  7. Oct 5, 2011 #6
    Jarfi, when you wonder about this you're on your way. Knowledge is like a flashlight, the more you know, the further you can see. Keep on learning, and look up the equations to see if you can find a answer to them. Here is a good place to ask.

    But when it comes to the way nature is in its smallest scale? Then you have to make a proposition, then test it, and as Phinds say. Someday we may have a final answer. To me it's all about what time is, but that's my view.

    Just don't give up on learning things because we can't give you a final answer, it will give you a platform to see better and create your own ideas.
  8. Oct 5, 2011 #7


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    If it is taught in your school that spacetime is quantized, that a bad thing.

    One of the problems with theories in phyics is that you never really prove anything, you just come to conclusions that do not seem to have any contraditions in reality and that give solid predictions and that can be falsified. BUT ... if one day a contradiction comes up ... POOF, there goes the theory; it's just been falsified.

    As to whether or not we'll ever know if spacetime is quantized, I'm pretty sure we'll never know that it is NOT quantized, because you can't prove a negative. All it would take to blow up that theory is a validated experiment that shows that it IS quantized.

    But as youron so rightly points out, none of that makes learning physics any less fun. In fact, it just ups the challenges.
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