Solution help for the Geodesic Equation

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SUMMARY

The discussion focuses on solving the geodesic equation for an asteroid entering Earth's atmosphere, utilizing initial conditions defined by a 4-velocity vector and a starting point in Riemann Space with Torsion = 0. The Schwarzschild metric is employed, with the Christoffel Symbol representing affinity and a null Ricci tensor indicating non-zero curvature. The user seeks a method to formulate the path "s" in the second-order geodesic differential equation, specifically through the integration of the geodesic equation while considering initial conditions.

PREREQUISITES
  • Understanding of Riemann Geometry and its application in physics
  • Familiarity with the Schwarzschild metric and its implications in general relativity
  • Knowledge of Christoffel Symbols and their role in geodesic equations
  • Proficiency in differential equations and integration techniques
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  • Study the derivation and application of the geodesic equation in general relativity
  • Learn about the Schwarzschild metric and its significance in astrophysics
  • Explore the role of the Ricci tensor in curvature and its implications for geodesics
  • Investigate numerical methods for solving differential equations in curved spacetime
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Physicists, mathematicians, and students specializing in general relativity, as well as anyone interested in the mathematical modeling of trajectories in curved spacetime.

Jack3145
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Let’s say an asteroid is about to enter earth’s atmosphere(it will burn up of course). The initially sitting is at:

[tex]point = [x_{0},y_{0},z_{0},t_{0}] = [r_{0},\\theta_{0},\\phi_{0},t_{0}][/tex]

With a 4-velocity:

[tex]V = [v_{1},v_{2},v_{3},v_{4}][/tex]

The momentum at 0+

[tex]p_{0+} = mass*V = mass*[v_{1},v_{2},v_{3},v_{4}][/tex]

The Riemann Geometry is Riemann Space with Torsion = 0. The metric is the Schwarzschild metric. Affinity is the Christoffel Symbol. Curvature is non-zero. And, the Ricci tensor is null.

My question is how do you formulate [tex]x^{i}[/tex] to attempt solve for the path, "s" in the second-order geodesic differential equation from the given initial 4-velocity vector and starting point?
 
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I am looking for how to solve the geodesic path, I. Something like this except taking into account initial conditions:

[tex]I = \int[(1-2m/r)^{-1} + r^{2}(d\theta/dr)^{2} + r^{2}(sin\theta)^{2}(d\phi/dr)^{2} - (1-2m/r)(dt/dr)^{2}]^{1/2} dr[/tex]
 
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The geodesic is a graph of many curves. You have to go piece-meal or one part at a time. Use the Geodesic equation to lesson the amount of unknowns:
 
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