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What are the uses of GR?

  1. Feb 14, 2009 #1
    As someone who has never gone through a formal study of GR and SR and whose knowledge of these subjects is at the most basic level I am glad to have found this site because by reading through the threads I am able to pick up interesting snippets of information.What I would like to ask is are there any practical applications of GR and indeed SR beyond just that of nuclear energy?
  2. jcsd
  3. Feb 14, 2009 #2
    GPS satellites and airplane navigation systems take into account GR & SR corrections, although we would not need the theory of relativity to make these corrections i.e. the tendency of clocks to drift aboard a supersonic jet could be corrected using empirical formulae.

    Mostly GR is used to understand astronomy and cosmology, which is not of any practical use.

    The combination of SR and quantum mechanics (in the form of relativistic QM or as Quantum Field Theory) is used to understrand properties of matter throughout modern chemistry, materials science, electronics, etc. It has been said that if it were not for the relativistic corrections to QM, then gold would not shine (of course this is not a technology, but is meant to convey how essential it is to understand relativistic QM to understand matter).
  4. Feb 14, 2009 #3
    Thank you confinement.I suspected that about SR but who knows what the future holds re practical uses?
  5. Feb 15, 2009 #4
    Airplane navigation systems? Apart from GPS, I've never heard of any other airplane navigation systems that take GR or SR into account. The inherent inaccuracy of IRS systems is way higher than any relativistic effects, and other sensors just use simple direct azimuth and distance readings from emitters on the ground, using high school math without any fancy corrections.

    And at the speed of even supersonic aircraft, relativistic effects are really tiny anyway.
  6. Feb 15, 2009 #5
    I imagine it's probably used quite a bit for spacecraft, like the Mars probes etc... Then again. maybe even there it's probably easier to just make small ad hoc corrections instead of really using GR...
  7. Feb 15, 2009 #6


    Staff: Mentor

    It got kind of hidden in confinement's post, but SR is essential to understanding the quantum nature of materials. This means that modern semi-conductor based electronics are a result of SR.

    For GR I also can only think of cosmology and GPS.
  8. Feb 15, 2009 #7
    Perhaps the most revolutionary application: how new ays of thinking about largely existing information can lead to incredible break throughs.
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