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Einstein and Lorentz

  1. Jan 5, 2015 #1
    I am hoping someone can help me with something. I want to go into the field of temporal physics and I was wondering if someone could help me understand why Einstein's E=mc2 isn't combined with Lorentz's factor ϒ=1/√1-(v2/c2) to further prove the light-speed barrier?
  2. jcsd
  3. Jan 5, 2015 #2


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    Staff: Mentor

    Both of these relationships are derived from the same underlying assumptions (the two postulates of special relativity - Google for "On the electrodynamics of moving bodies" to find Einstein's 1905 paper on SR) as the light-speed limit. Thus, using them to "further prove" the lightspeed limit doesn't tell us anything new; it just shows that the assumptions that lead to the light-speed limit lead to the light-speed limit.
  4. Jan 6, 2015 #3


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    Also the relation [itex]E=mc^2[/itex] is already given at a certain Reference fram (the rest frame of the object of mass [itex]m[/itex] ). So how would you put a gamma factor?
  5. Jan 6, 2015 #4
    Thank you for the reference, Nugatory. Also, could you recomend any books or sights that are credited and discus the possibility of Tachyons?
  6. Jan 6, 2015 #5


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    Science Advisor

    Jorlack, you are right. One way of writing the energy equation is
    ##E=\gamma m c^2##
    The common equation ##E=mc^2## is only valid for particles at rest, when ##\gamma = 1##.
  7. Jan 7, 2015 #6
    ##\gamma = 1## when the velocity of the said object or particle is 0. Therefore the Lorentz factor would equal ##1/1## or simply, 1.
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