Is My Derivation of the Dominant Non-Linear Terms in MTW Exercise 19.3 Correct?

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SUMMARY

The discussion focuses on the derivation of dominant non-linear terms in the context of MTW Exercise 19.3, specifically addressing the proportionality of these terms to the square of (M/r)². The participant derives the metric perturbation h00 and explores the implications of the quadrupole moment Qij in the new coordinate frame, ultimately leading to the metric g00 = -1 + A0/2r - 6Qii/A0r². The participant questions the absence of M² in their derivation and references T'hooft's GR lectures to support their findings.

PREREQUISITES
  • Understanding of general relativity concepts, particularly metric perturbations.
  • Familiarity with the MTW textbook, specifically Exercises and Chapters 18 and 19.
  • Knowledge of quadrupole moments and their role in gravitational theories.
  • Ability to perform tensor calculus and coordinate transformations in general relativity.
NEXT STEPS
  • Review the derivation of metric perturbations in general relativity from MTW, focusing on Exercise 19.3.
  • Study T'hooft's General Relativity lectures, particularly Equation 7.4, for insights on non-linear terms.
  • Examine Landau and Lifgarbagez's treatment of gravitational fields and metric perturbations.
  • Explore the implications of quadrupole moments in gravitational wave physics and their mathematical representation.
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Students and researchers in theoretical physics, particularly those studying general relativity and gravitational perturbation theory, will benefit from this discussion.

zn5252
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hello
In part 8) of this Ex, MTW mentions that the dominant non linear terms must be proportional to the square (M/r)2. The problem is that since I got the value :
h00 = A0/r + 6Qijninj/r3 (Qij is the quadrupole moment) and following the translation of coordinates suggested by MTW which is found in linearized theory , eq 4a of MTW chapter 18-Box18.2 , xjnew= xjold - Bj/A0 where the Bj = 6Qijni/r which leads to the new metric perturbation in the new coordinate frame : h00new = h00old - εj,j - εj,j
where the εj = - Bj / A0
now I need to derive the εj with respect to j which leads to εj,j = 6Qii/A0r2 - 12 Qijxixj/A0r4 (I discard this last term)
And the metric would then be :
g00 = -1 + A0/2r - 6Qii/A0r2

I'm I right up to this point ? Did I miss anything perhaps ?
the poblem is that I would not see where the M2 would come out here ? I have the r2 and also the first linear term but the second term is proportional to the quadrupole moment divided by r2A0 which means no M squared ? and the A0 is linear in M
 
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Full solution could be found in Landau and Lifgarbagez page 359 for those interested...
 

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