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I have to correct my answer written here before. The Reissner-Nordström metric has the shape (see https://de.wikipedia.org/wiki/Reissner-Nordstr%C3%B6m-Metrik): \begin{equation} \mathrm{d}s^2 = -\left(1-\frac{2GM}{c^2 r} + \frac{Q^{2} K G}{ c^4 r^2}\right)c^2 \mathrm{d}t^2 +\left(1-\frac{2GM}{c^2 r} + \frac{Q^{2} K G}{ c^4 r^2}\right)^{-1} \mathrm{d}r^2 + r^...


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Too long for a comment, I refer you back to @JamesK's answer for the answer. In Space Exploration SE See: Calculating the planets and moons based on Newtons's gravitational force How to calculate the planets and moons beyond Newtons's gravitational force? Use a reasonable ODE solver; at least RK4 (the classic Runge-Kutta method) or better. Do not use just ...


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If I follow the code, you are using Kepler's formulae to calculate the distance and speed of the planet, and then increasing the planet's position using speed × time. That is essentially a form of Euler's method for solving numerical differential equations, and as such it may be sensitive to initial conditions and rounding. You've chosen a small step size ...


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This is an answer that I am writing up based on comments by ProfRob and Mike G. The meaning of 'beta' in these plots is the slope of the line. The figure itself is from Radio spectral properties of star-forming galaxies in the MIGHTEE-COSMOS field and their impact on the far-infrared-radio correlation (arXiv link). From the caption of the figure in the ...


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The Roche lobe is a gravitational potential well of a two-body configuration. Technically, it is the potential energy per unit test mass which is orbiting the center-of-mass of a binary-star system at the same rate as the two stars. It is often depicted with equipotential surfaces and the 5 Lagrange points. The Roche lobe includes gravitational and ...


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