Comments by "Anony Mousse" (@anon_y_mousse) on "How NANOGrav Uses Dead Stars to Detect Spacetime Ripples" video.

They're going to need significantly more points to prove anything, not just pulsars, but observations of them. Maybe landing multiple probes on the surface of multiple planets in the solar system would be a good start, but we also need some observations from at least the next system over.
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@charlesbrightman4237 A lot of our math is based on inventing language to describe what's observed. Yes, I'm calling math a language, and it's incomplete like my answer. There are certain assumptions inherent in the math which might wipe out everything we think we know if they're ever proven incorrect, but for now things mostly work. Time and space are kind of unknown and I've yet to see an experiment which validly explains them, though I've seen experiments which people think explain them. I think the majority of your questions are either answered by one answer or won't be adequately answered until long after we're all dead. Although, to circle back around to the photon, it's not the expanding of space that causes the red shift but rather the travel of the photon through space. Whether that means anything regarding propulsion I couldn't say, but presumably every particle decays and regardless of whether a photon is considered a particle or not, it will decay too.
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@charlesbrightman4237 With regards to the energy in a red shift, it dissipates in all directions. For all the rest, good questions.
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