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Seeking the unknown in the known (part 1, energy)

  1. Sep 2, 2003 #1
    A few years ago it came to my attention that everything somehow always related to energy. But the more I thought about it, the more I realized that I don't understand what energy actually is . There isn't a very good explanation of energy in my physics textbooks, only the basic stuff about energy. And my physics teacher sounds like she has never heard of the subject physics .

    I'm hoping for some good explanations on energy (I say explanations and not explanation, because I think that there are more perspectives on this subject than just one).
     
  2. jcsd
  3. Sep 3, 2003 #2
    The concept of energy is classical, but when we convert it to a quantum mechanical concept we find that it is just the change of the phase of a quantum mechanical amplitude with time.That is what makes energy so important, it is related directly to how systems change with time. The quantum mechanical equation that describes the energy of a system is called the Hamiltonian, and it tells us how a system changes with time. If we want to make a system change with time we have to put some energy into it, which is why we heat a mixture of chemicals to make them react faster, etc..

    That should give you some perspective on the true nature of energy.
     
  4. Sep 4, 2003 #3
    Thanks tyger, finally I'm learning some of the good stuff

    Could you please recommend a book on this subject? I'd really appreciate it.

    I thank you in advance,

    Astrophysics
     
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