Geodesic Equation: Lagrange Approximation Solution for Schwarzschild Metric

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SUMMARY

The discussion centers on the geodesic equation and its Lagrange approximation solution within the context of the Schwarzschild metric. The equation presented is d/ds(mgμνdxν/ds)=m∂gμν/∂xλdxμ/ds dxν/ds, which describes the motion of test particles in a gravitational field. The Schwarzschild metric is defined as ds²=(1-rs/r)dt²-(1-rs/r)⁻¹dr²-r²sin²θdφ². A key point of contention is the interpretation of the partial derivative ∂gμν/∂xλ, which is not zero due to the metric coefficients being functions of the radial coordinate r, contradicting the initial assertion that the sun has no gravitational effect on test particles.

PREREQUISITES
  • Understanding of geodesic equations in general relativity
  • Familiarity with the Schwarzschild metric
  • Knowledge of Lagrange mechanics
  • Basic concepts of differential geometry
NEXT STEPS
  • Study the derivation of the Schwarzschild metric in detail
  • Learn about geodesic equations in the context of curved spacetime
  • Explore Lagrangian mechanics and its applications in general relativity
  • Investigate the implications of metric coefficients on gravitational effects
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This discussion is beneficial for physicists, mathematicians, and students of general relativity who seek to deepen their understanding of gravitational effects in curved spacetime, particularly in relation to the Schwarzschild solution.

AleksanderPhy
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Hello so if we have geodesic equation lagrange
approximation solution:
d/ds(mgμνdxν/ds)=m∂gμν∂xλdxμ/ds dxν/ds. So if we have schwarzschild metric (which could be used to describe example sun) which is:ds2=(1-rs/r)dt2-(1-rs/r)-1dr2-r2[/SUP]-sin22. But that means that ∂gμν/∂xλ=0. So that means that first equation will equal to zero so that means that sun has no gravity effect to test particle. But according to my knowledge sun does pull things towards itself.
 
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AleksanderPhy said:
that means that ∂gμν/∂xλ=0.

No, it doesn't. The metric coefficients are functions of ##r##, which is one of the ##x^\lambda##.
 

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