I wonder what the final nail in the coffin will be for MOND. It seems like there’s new observations every few months supporting Lambda-CDM (even if it’s obviously not complete) over MOND. At some point, MOND is just a clever idea that was worth exploring and didn’t pan out.
I follow this stuff (as a non-physicist) so I understood it. It’s a pretty shallow article and mentions there there’s still evidence for the widely-accepted Lambda-CDM model. But like most coverage of MOND it declines to give good alternate explanations for specific key observations like the Bullet Cluster, gravitational lensing, and galactic outer rotational speeds.
So yeah a new observation that fits better with MOND than LCDM is certainly interesting, but it doesn’t flip the tables unless it does a better job explaining the prior phenomena too.
I understand the two theories and the difference between them, but when my brain tries to comprehend how gravity actually works I experience a comprehension failure.
Haha, well if it’s any consolation, nobody fully understands it. That’s why we’re still looking at various theories of quantum gravity or even random gravity.
oh boy, get ready people. it starts with a movie, then it’s a debut single, then you’re buying the fanzines, the hats, the shirts. this ends in commemorative plates.
Isn’t an event horizon just a question of being dense enough to bend light past the point of no escape?
A hollow planet supporting a detached core with enough density to have an event horizon seems kinda ridiculous… If even light can’t escape it, I don’t see some rocky ‘shell’ withstanding that much gravity. Any hollow section would have collapsed well before reaching the point of the planet’s densest point forming an event horizon.
What matters is the total mass of the black hole, not its density. If you replaced Earth’s core with a black hole of the same mass, the gravity you’d feel at the surface (or beneath the surface) would be the same. You’d only notice a difference if you were in the hollow region formed by removing the core.
The way I see it, the real problem with a planet like Earth is that because the inside is so hot, the inner parts are too soft to support their own weight, and the crust is probably too fragile to support its own weight. That’s not a problem, though, in an asteroid or a planet that’s solid all the way through.
Depending on the mass of the black hole, the “shell” doesn’t need to be a shell it could be effectively completely solid with an atom sized black hole at the centre.
PBH’s as discussed in this article have pretty wild mass ranges, so anything is possible. It’s entirely possible to have black holes so small they can’t easily absorb new matter as they’re smaller than protons. Tiny black holes only have large surface gravity, nothing noteworthy at a distance.
After more than a century of speculation, data seem to confirm that Betelgeuse (the brightest star in the Orion constellation, shown here) has a much smaller star as an orbital companion.
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Two independent studies found evidence of a star about the same mass as the sun, orbiting Betelgeuse about once every 2,100 days.
You got it wrong - the poster above is not trying to prove the astronomical phenomenon through a show, the poster is saying that the show itself (called Big Bang) is real. It’s simply a joke.
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