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Coordinate acceleration without a Force

  1. Feb 26, 2008 #1
    Coordinate acceleration without a Force !!!!!!!!

    Hi
    GR had presented two types of motion , the geodesic motion and the non-geodesic motion . We know that the geodesic motion equation is :

    [tex]\[
    \frac{{d^2 x^\alpha }}{{d\tau ^2 }} + \Gamma _{\beta \mu }^\alpha \frac{{dx^\beta }}{{d\tau }}\frac{{dx^\mu }}{{d\tau }} = 0
    \][/tex]
    and ( as I know ) the equation of the non-geodesic motion in the derivative of the four - momentum :
    [tex]\[
    F^\lambda = \frac{{dP^\lambda }}{{d\tau }} + \Gamma _{\mu \nu }^\lambda U^\mu P^\nu
    \][/tex]
    and from this equation we can calculate the equation of the coordinate acceleration :
    [tex]\[
    a^\lambda = \frac{1}{m}\left( {\frac{{d\tau }}{{dt}}} \right)^2 \left[ {F^\lambda - \left( {\frac{{u^\lambda }}{c}} \right)F^0 } \right] + \left( {\frac{{u^\lambda }}{c}} \right)\Gamma _{\mu \nu }^0 u^\mu u^\nu - \Gamma _{\mu \nu }^\lambda u^\mu u^\nu {\rm }........{\rm Eq(1) }
    \][/tex]
    but I saw and worked with a different equation for the coordinate acceleation :
    [tex]\[
    a^\lambda = \left( {\frac{{u^\lambda }}{c}} \right)\Gamma _{\mu \nu }^0 u^\mu u^\nu - \Gamma _{\mu \nu }^\lambda u^\mu u^\nu
    \][/tex]
    and I saw that this equation is Eq1 with zero four - force . without force the motion won't be non-geodesic any more .
    How ???
    thanks
     
  2. jcsd
  3. Mar 22, 2008 #2
    Hello !!!!!!!!!!!!!!!!!!
    It's been nearly a month since I put the theard and I didn't find any replies .
    Is there is anything wrong in it ?
     
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