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Which is it?

  1. Jun 25, 2003 #1
    This question may sound stupid, but I really don't know what to think. You see, it has been my understanding that energy is just an expression of the movement of physical things (this is simplifying, but it suffices). However, I had also believed that matter was just congealed energy. I hadn't though of these two concepts as conflicting until recently.

    So, which is it?

    Any help is appreciated.
  2. jcsd
  3. Jun 25, 2003 #2
    Energy and time are related,

    and that is why energy is so important. The classical quantity energy is proportional to the rate of quantum mechanical phase change with time, i.e. the QM frequency. The Hamiltonian Equation and its solutions, of which Schrodinger's Equation is a version, tell how a system changes with time.

    If we want to make a stable system undergo change with time we must put energy into it.

    Many states (particles) have "rest energy" which is a way of saying that their phase changes with time even if we don't put any more energy into them. This energy (QM frequency) is generaly unavailable to do work. If the energy depends upon position it's called potential energy, upon motion (usually expressed as momentum) it is kinetic energy. If it is inherent it is rest energy.

    When you learn more about it you will see that there is no conflict among the different forms of energy.
  4. Jun 26, 2003 #3
    Re: Energy and time are related,

    Your explanation makes sense. Let's see if I understand it correctly: Energy is what causes phase changes over time, but that is Kinetic or Potential Energy. "Rest energy" would be what is supposedly "congealed" into a particle, according to layman explanations. Is that close to right?
  5. Jun 26, 2003 #4
    Energy is the STUFF of the Universe. It is the sum total of everything. It takes on many guises - there is kinetic energy (energy of movement), field energy, matter energy, radiation energy (as in emr), and I also believe there is dark energy otherwise known as quintessence or ether energy. That's about it. It is the energy that gives the universe its form. I believe that the word space is used incorrectly as if it was a substance in its own right. To me space is not a form of energy but merely the mathematical container which we use mentally to hold the energy of the universe.
  6. Jun 29, 2003 #5
    Re: Re: Energy and time are related,

    When I'm talking about phase change, I mean the phase of a quantum mechanical amplititude, commonly known as a wave function. Any type of wave has a phase and modulus, and can be described by how they vary in space and time.

    I can't describe it any better with out getting quite a bit more mathematical.
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