Logo Research Diary

22 - Wednesday

I've been sick for the last week or so, but tonight I updated my code to produce plots that are analogous to those Josh created for mapping to Kruskal-like coordinates.

There is some ambiguity about what Josh is referring to as out vs in going. He has added an ad-hoc sign change to the equations of motion.  At first glance this seems fairly valid, the Schwarzschild metric causes the direction of null trajectories to flip when crossing the horizon. I'll need to ask about this, it's not really part of the ODE, but there's definitely some sort of justification.

At this point, I've pretty much covered everything Josh had done. Now I can start investigating some of the points raised in my meeting with Tim and Josh: 16 - Thursday

On the left are Josh's plots, and mine on the right.

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Article ImageYou can see in these plots in particular, the effect of Josh's sign flip when crossing the horizon
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Article ImageIt's also noticeable here, but it's a little more subtle.