I know next to nothing about dark matter (and, come to that, gravity), but reading about the topic still fascinates me. In this article, I was particularly struck by one paragraph:
> Mond’s main postulate is that when gravity becomes very weak, as occurs at the edge of galaxies, it starts behaving differently from Newtonian physics. In this way, it is possible to explain why stars, planets and gas in the outskirts of over 150 galaxies rotate faster than expected based on just their visible mass. But Mond doesn’t merely explain such rotation curves, in many cases, it predicts them.
Reliable prediction by a theory is pretty persuasive, surely?
AFAIK, a lot of effort/resource has been put in to finding dark matter. (Most recent article I read was, er, today [1].) But so far, no smoking gun. Exploring alternative theories can't hurt.
I hope that this item gets re-upped by HN's powers that be. I am keen to see this discussed by commenters with the chops to wade in with informed, authoritative views.
Seems likely to me that "dark matter" is just the latest catch-all for theorical numbers not matching reality. There is a rich history of science postulating a McGuffin until a stronger theory comes along and I see no reason that some untrackable "dark matter/energy" actually exists.
Not so long ago light used to travel through the "aether". Before we knew of germs, we blamed the "miasma". Something that has form but no detail needs a name but it is key to not rely on vaguely formed concepts as a legitimate answer.
> Mond’s main postulate is that when gravity becomes very weak, as occurs at the edge of galaxies, it starts behaving differently from Newtonian physics. In this way, it is possible to explain why stars, planets and gas in the outskirts of over 150 galaxies rotate faster than expected based on just their visible mass. But Mond doesn’t merely explain such rotation curves, in many cases, it predicts them.
Reliable prediction by a theory is pretty persuasive, surely?
AFAIK, a lot of effort/resource has been put in to finding dark matter. (Most recent article I read was, er, today [1].) But so far, no smoking gun. Exploring alternative theories can't hurt.
I hope that this item gets re-upped by HN's powers that be. I am keen to see this discussed by commenters with the chops to wade in with informed, authoritative views.
[1] https://www.theguardian.com/science/2022/jul/07/dark-matter-...