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Energy:The real thing

  1. Jan 4, 2007 #1
    What exactly makes forms of energy different from each other?

    Can we say that mass is a dense concentration of energy?o:)
     
  2. jcsd
  3. Jan 4, 2007 #2
    Hey pls sum1 answer this
     
  4. Jan 4, 2007 #3

    disregardthat

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    Energy is in some way the same as mass yes. I believe it 'connects' the elementary point(0-dimensional) particles to eachother, making particles like protons, and neutrons. And it also connects them to eachother making atoms, and molecules.

    It has the effect of increasing the mass of the object. Well, I don't know if this is 100% correct, but no one else is answering...
     
  5. Jan 4, 2007 #4

    cristo

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    Energy can be defined as the abilty for a force to do work. So, the different forms of energy arise due to the variety of different forces.
     
  6. Jan 4, 2007 #5
    Hey ppl i greaatly appreciate ur views.So i gues we CAN say mass is concentration of energy.So now i hav another doubt,Why are forms of energy different?
     
  7. Jan 4, 2007 #6
    Different forces?Forces all of em hav the same effects!
     
  8. Jan 4, 2007 #7

    ZapperZ

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    For those of you who think that mass can be defined as nothing more than "concentrated energy", consider the following:

    Take an example of "pure" energy such as photons. Now clump them all very tightly to form as mass per the scenerio of the OP. Now explain to me the following:

    1. photons have no charge, yet, electron, quarks, etc... all do. Where do these charges come from?

    2. Photons have spin of 1. elementary fermions have spins of 1/2. How do you get the basic projection of the "units" of 1 to get spin of 1/2?

    3. Photons do not interact via the weak interaction (they don't, at this point, participate in strong interactions either, but in some postulated theory, they might in higher order interactions). Yet, we know many particles that do. Where did that come from?

    Zz.
     
  9. Jan 4, 2007 #8

    russ_watters

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  10. Jan 4, 2007 #9
    Hi ZapperZ,

    see first of all u cannot clump energy in motion(photons CANNNNOT exist at rest).And hence the energy together wont hav spin.So this situation is INVALID SIR!!
     
  11. Jan 4, 2007 #10
    and ZapperZ,When mass is "converted" to energy on nuclear reactions(say light energy therefore photons),how does spin change suddenly?????
     
  12. Jan 4, 2007 #11
    Also ZZapperZ,light shud create gravity if focussed to such an extent that it may hav a very strong gravitational field.This is as energy has the same effects of mass!
     
  13. Jan 4, 2007 #12

    ZapperZ

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    But isn't that what YOU are claiming or asking in your original question? A "photon" is what most would consider as a "pure energy". So? I was merely demonstrating what you are asking for and then I turn around and applied it to see what kind of results one would get.

    So it appears that you have answered your own question.

    This is because the mass just doesn't appear out of nowhere. When a photon is converted into mass via pair production, you have several things that goes on (i) the net charge is conserved because of the production of the particle and its antiparticle partner (ii) the spin is conserved because of the same reason, and (iii) momentum is conserved because such a process can only occur in the vacinity of a more massive particle to take up the missing momentum. The same in a nuclear reaction. There are other particles involved in the process. You just don't see a particle spontaneously dissolve into just pure energy all by itself with nothing else going on.

    It isn't as simple as "mass is just a concentration of energy".

    Zz.
     
  14. Jan 4, 2007 #13

    ZapperZ

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    Show me where this has occured and been observed.

    Zz.
     
  15. Jan 4, 2007 #14
    and the light q sry
    it SHUD occur thats wat im saying.U cannot feel it
     
  16. Jan 4, 2007 #15
    cant the nuclear reaction example be due to change of density of energy!IN GR dense energy curves spactime more than energy spread out
     
  17. Jan 4, 2007 #16
    Here in the nuclear reaction case,mass is CONVERTED to energy.Im sry as i wrote energy>>mass
     
    Last edited: Jan 4, 2007
  18. Jan 4, 2007 #17

    ZapperZ

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    It doesn't matter. There is STILL a bunch of particles involved. In the matter-antimatter anhilation, you STILL need two particles to maintain the conservation. You just don't have a particle spontaneously disappear into energy with nothing else involved.

    Zz.
     
  19. Jan 4, 2007 #18
    Hey Zapper ok so HOW exactly does mass get converted into energy.From scratch pls explain
     
  20. Jan 4, 2007 #19

    ZapperZ

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    Hell if I know. I'm not the one who wants to make any speculation. Someone else might.

    However, all I care about is to make sure someone point out the inconsistency with your original question. When I see a series of responses of people agreeing with that concept, then I see that something hasn't been thought through carefully.

    Zz.
     
  21. Jan 4, 2007 #20
    PLsss im not trying to contradict u ,but only trying to learn.Please enlighten me.I shall chek in 2morow.Good nght
     
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