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Proper movement, reference frames and gravitational waves

  1. Feb 17, 2016 #1
    So apparently electrons don't orbit the nucleus of atoms so I'm assuming the lack of movement means that no energy from the atom is radiated away from an atom due to minuscule gravitational waves, over the life of the universe.
    But gravitational waves have got me thinking about reference frames, can anything ever be stationary to the reference of space-time? I learnt in HS physics class that there is no such thing as an objective reference frame, but wouldn't space-time itself be an objective reference frame?
    Because it's my understanding that movement of large celestial bodies creates gravitational waves, but can anything in the universe ever not move? And thus not create gravitational wave?
    Or is it only radial movement (orbits) that radiate gravitational energy?
    So otherwise can an atom exist in the universe not radiate energy in the form of minuscule orders of magnitude gravitational waves, and what happens to an atom trillions and trillions of years from now after it's radiated all it's 'energy' away?
  2. jcsd
  3. Feb 18, 2016 #2
    no, yes. see electron ORBITALS....the most accurate model is one where electrons are standing probability waves not billiard ball type objects in simple orbits. In other words, quantum mechanics not classical physics is the best model. At subatomic scales, things interact is discrete steps, usually multiples of Planck's constant,h, not continuous energies.

    yes, no. I think you mean INERTIAL frame and, yes, one is as good as another. Yours is different from mine right now, but so slow it hardly matters. Near light speed however, there are major differences described by special relativity, length contraction and time dilation.

    What is 'objective', that is invariant in the language of relativity, is the space time interval. Space contracts and time dilates and despite our everyday experience are NOT constant. Only the speed of light is constant. Thiese behaviors what Einstein encoded in his theory of Special Relativity.

    The first few sections here are verbal not mathematical decriptions: https://en.wikipedia.org/wiki/Special_relativity

    In general, orbital motion, say circular or elliptical, will radiate gravitational waves. [PS: 'radial movement' is perpendicular to circular orbital movement.] Circular orbits are a special case of acceleration in which direction, but not velocity, changes. The BOHR model has 'rules' for which electron orbits don't radiate, but I'm pretty sure there is no good rationale. When electrons jump from one orbital to another, they do radiate. Quantum mechanics likely provides detailed insights about orbitals and radiating but I don't know about the details. See https://en.wikipedia.org/wiki/Bohr_model for some 'rules and regulations' regarding electrons bound to nuclei; these Bohr rulesare based on observations, measurements, not first princples.
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