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I was under the impression that it was not fully rigorously accounted for because its not exactly a simple calculation. So galaxies were still being modeled wi

I was under the impression that it was not fully rigorously accounted for because its not exactly a simple calculation. So galaxies were still being modeled with newtonian physics in at least part of the calculations which neglects field self-interactions.

pfdietz 4y ago
Ordinary matter in the galaxies cannot explain the rotation curves. Something dark (that doesn't interact with electromagnetic radiation) is needed. Also, the mass in the universe cannot be all baryonic, since that would make primordial nucleosynthesis inconsistent with observed abundances of various light isotopes.
- peteradio 4y ago
  You are repeating the same dominant theory and don't address that at least some of the excess can be accounted for by more rigorous computation...
  - pfdietz 4y ago
    I should be clear: ordinary matter cannot explain the rotation curves with conventional gravity. One can come up with ad hoc modified theories of gravity, but none appears to be consistent with all the evidence.
    - Maursault 4y ago
      See my comment above. Watch the whole video. Once you understand it, which you will, you will never talk about galaxy rotation curves again. Dark Matter may still be necessary, as a lot of unexplained has been dumped into the theory, but it is no longer necessary to explain galaxy rotation curves as a much simpler explanation exists, namely, gravitational tidal forces created by other galaxies in a cluster, which is very well understood and entirely explains curves of galaxy rotation and solves the winding problem.
      - pfdietz 4y ago
        Is there a paper on that? The talk was ten years ago, so I assume the idea would have appeared in print by now, if the idea actually worked. I looked under his name on arxiv and didn't find anything on this topic.
        bdhcuidbebe 4y ago
        Bro just trust youtube kkek
        Maursault 4y ago
        Will a paper be more convincing? I think there's a book. Write the author and ask him.[1] But the simple and unambiguous explanation of galaxy cluster tidal forces is devastating to Dark Matter Theory in regards to galaxy rotation curves. Why anyone is still talking about Dark Matter as a viable explanation for galaxy rotation curves likely has to do with the paradigmatic nature of science which resists any change, plus that there are myriads that have wasted entire academic and scientific careers on Dark Matter. [1] alex@SensibleUniverse.net
        pfdietz 4y ago
        A paper would tell one the thing passed peer review, and also let us look for papers publishing rebuttals. If it sank without a trace in the refereed literature, that's a screaming red flag. I am very dubious the idea is correct. If objects at large distances from the galaxy center have these large relative velocities induced by external objects they wouldn't be bound to the galaxy.
        Maursault 4y ago
        > If objects at large distances from the galaxy center have these large relative velocities induced by external objects they wouldn't be bound to the galaxy. Right. Tides must be caused by something other than the Moon because it's just too far away. No, wait, large masses have do have an effect across large distances. There are no isolated reference frames without gravity. Galaxy clusters do orbit around their center of gravity. Would you like to know how many theories in theoretical physics been proven? Precisely none of them, including Dark Matter Theory. This dubiousness is specious and, fwiw, a bandwagon argument.
    - peteradio 4y ago
      You still haven't engaged on the idea that we haven't been doing full fidelity calculations based on vanilla general relativity and doing so yields non-negligible impacts on the lensing apparently. If you are using models which were meant to have their numbers crunched on an 80s pc then its possible it got too dumbed down. The assertion is that the theoretical error bars were improperly computed and should have been much larger.
- Maursault 4y ago
  > Ordinary matter in the galaxies cannot explain the rotation curves. The observations of Fritz Zwicky and Jan Oort were of spiral galaxies in isolation, which led to the need for Dark Matter to explain the rotation curives. Once the entire galaxy cluster is considered, it becomes evident that a spiral galaxy is not an isolated reference frame and that Dark Matter is no longer necessary to explain galaxy rotation curves.[1] [1] https://www.youtube.com/watch?v=PL0ewiwqoTw https://www.youtube.com/watch?v=PL0ewiwqoTw
  - AnIdiotOnTheNet 4y ago
    Hey I recognize that name. He's the guy who wrote a book about some new cosmology he came up with from making a small modification to relativity that he claimed, among other things and IIRC, explained the Ganymede Mass Anomaly, that black holes were time-reversed white-holes from the other (time reversed from us) side of a hyperspherical universe, that the expansion of the universe is an illusion created by the curvature of said hpyersphere, and probably some other stuff I don't remember. His work is attractive to laymen like myself, but any rational person has to wonder why, if his claims have any validity, he has been ignored completely by the wider physics community (which is to say, people who actually know shit, unlike most of us). Your call to "watch the video and you'll never talk about galaxy rotation curves again" sounds a whole lot like similar statements made about such nonsense as "There are no forests on Earth", so if you honestly believe this guy should be taken seriously for some reason I would suggest a change in approach.
    - Maursault 4y ago
      Near as I can tell, Alexander Franklin Mayer is an MIT educated physicist that was associated with Stanford's Department of Physics, where he lectured.[1] He published a book titled On the Geometry of Time in Physics and Cosmology and the Fall of the Canonical Cosmological Model[2] I can find no evidence or even remote hints of his connection to anything you have listed. But even as generous as your comment is, fundamentally you are making an ad hominem argument, effectively saying, "this guy is a crackpot, why should we listen to him?" It doesn't matter who he is. One must examine the assertions and findings detailed in his lecture, and only if flaws can be found there can his tidal theory explaining galaxy rotation curves be defeated. As such, between you and dubious commenter pfdietz, Mayer's lecture, assertions, findings and conclusions stand entirely unopposed by HN commenters. There seems to be a strong sense of bandwagon among HN members, that because Dark Matter Theory is now paradigmatic, Dark Matter has to be proven not to exist for it to be defeated. But proving things don't exist is not the realm of science while finding simpler explanations for physical phenomena often is. Mayer's explanation for galaxy rotation curves is simple, elegant, and compelling, and it is interesting that no one at HN wants to take it head on but instead will employ the all too common hand wave and other fallacious arguments. Look at it. Figure out why it is wrong or don't. But the argument that if it was true we would all know about it and Mayer would be famous is not in the slightest way persuasive. [1] https://web.archive.org/web/20060207030527/http://www.stanford.edu/~afmayer/ https://web.archive.org/web/20060207030527/http://www.stanfo... [2] https://www.sensibleuniverse.net/pages/book.html https://www.sensibleuniverse.net/pages/book.html

pfdietz 4y ago

Ordinary matter in the galaxies cannot explain the rotation curves. Something dark (that doesn't interact with electromagnetic radiation) is needed. Also, the mass in the universe cannot be all baryonic, since that would make primordial nucleosynthesis inconsistent with observed abundances of various light isotopes.

peteradio 4y ago
You are repeating the same dominant theory and don't address that at least some of the excess can be accounted for by more rigorous computation...
- pfdietz 4y ago
  I should be clear: ordinary matter cannot explain the rotation curves with conventional gravity. One can come up with ad hoc modified theories of gravity, but none appears to be consistent with all the evidence.
  - Maursault 4y ago
    See my comment above. Watch the whole video. Once you understand it, which you will, you will never talk about galaxy rotation curves again. Dark Matter may still be necessary, as a lot of unexplained has been dumped into the theory, but it is no longer necessary to explain galaxy rotation curves as a much simpler explanation exists, namely, gravitational tidal forces created by other galaxies in a cluster, which is very well understood and entirely explains curves of galaxy rotation and solves the winding problem.
    - pfdietz 4y ago
      Is there a paper on that? The talk was ten years ago, so I assume the idea would have appeared in print by now, if the idea actually worked. I looked under his name on arxiv and didn't find anything on this topic.
      - bdhcuidbebe 4y ago
        Bro just trust youtube kkek
      - Maursault 4y ago
        Will a paper be more convincing? I think there's a book. Write the author and ask him.[1] But the simple and unambiguous explanation of galaxy cluster tidal forces is devastating to Dark Matter Theory in regards to galaxy rotation curves. Why anyone is still talking about Dark Matter as a viable explanation for galaxy rotation curves likely has to do with the paradigmatic nature of science which resists any change, plus that there are myriads that have wasted entire academic and scientific careers on Dark Matter. [1] alex@SensibleUniverse.net
        pfdietz 4y ago
        A paper would tell one the thing passed peer review, and also let us look for papers publishing rebuttals. If it sank without a trace in the refereed literature, that's a screaming red flag. I am very dubious the idea is correct. If objects at large distances from the galaxy center have these large relative velocities induced by external objects they wouldn't be bound to the galaxy.
        Maursault 4y ago
        > If objects at large distances from the galaxy center have these large relative velocities induced by external objects they wouldn't be bound to the galaxy. Right. Tides must be caused by something other than the Moon because it's just too far away. No, wait, large masses have do have an effect across large distances. There are no isolated reference frames without gravity. Galaxy clusters do orbit around their center of gravity. Would you like to know how many theories in theoretical physics been proven? Precisely none of them, including Dark Matter Theory. This dubiousness is specious and, fwiw, a bandwagon argument.
  - peteradio 4y ago
    You still haven't engaged on the idea that we haven't been doing full fidelity calculations based on vanilla general relativity and doing so yields non-negligible impacts on the lensing apparently. If you are using models which were meant to have their numbers crunched on an 80s pc then its possible it got too dumbed down. The assertion is that the theoretical error bars were improperly computed and should have been much larger.
Maursault 4y ago
> Ordinary matter in the galaxies cannot explain the rotation curves. The observations of Fritz Zwicky and Jan Oort were of spiral galaxies in isolation, which led to the need for Dark Matter to explain the rotation curives. Once the entire galaxy cluster is considered, it becomes evident that a spiral galaxy is not an isolated reference frame and that Dark Matter is no longer necessary to explain galaxy rotation curves.[1] [1] https://www.youtube.com/watch?v=PL0ewiwqoTw https://www.youtube.com/watch?v=PL0ewiwqoTw
- AnIdiotOnTheNet 4y ago
  Hey I recognize that name. He's the guy who wrote a book about some new cosmology he came up with from making a small modification to relativity that he claimed, among other things and IIRC, explained the Ganymede Mass Anomaly, that black holes were time-reversed white-holes from the other (time reversed from us) side of a hyperspherical universe, that the expansion of the universe is an illusion created by the curvature of said hpyersphere, and probably some other stuff I don't remember. His work is attractive to laymen like myself, but any rational person has to wonder why, if his claims have any validity, he has been ignored completely by the wider physics community (which is to say, people who actually know shit, unlike most of us). Your call to "watch the video and you'll never talk about galaxy rotation curves again" sounds a whole lot like similar statements made about such nonsense as "There are no forests on Earth", so if you honestly believe this guy should be taken seriously for some reason I would suggest a change in approach.
  - Maursault 4y ago
    Near as I can tell, Alexander Franklin Mayer is an MIT educated physicist that was associated with Stanford's Department of Physics, where he lectured.[1] He published a book titled On the Geometry of Time in Physics and Cosmology and the Fall of the Canonical Cosmological Model[2] I can find no evidence or even remote hints of his connection to anything you have listed. But even as generous as your comment is, fundamentally you are making an ad hominem argument, effectively saying, "this guy is a crackpot, why should we listen to him?" It doesn't matter who he is. One must examine the assertions and findings detailed in his lecture, and only if flaws can be found there can his tidal theory explaining galaxy rotation curves be defeated. As such, between you and dubious commenter pfdietz, Mayer's lecture, assertions, findings and conclusions stand entirely unopposed by HN commenters. There seems to be a strong sense of bandwagon among HN members, that because Dark Matter Theory is now paradigmatic, Dark Matter has to be proven not to exist for it to be defeated. But proving things don't exist is not the realm of science while finding simpler explanations for physical phenomena often is. Mayer's explanation for galaxy rotation curves is simple, elegant, and compelling, and it is interesting that no one at HN wants to take it head on but instead will employ the all too common hand wave and other fallacious arguments. Look at it. Figure out why it is wrong or don't. But the argument that if it was true we would all know about it and Mayer would be famous is not in the slightest way persuasive. [1] https://web.archive.org/web/20060207030527/http://www.stanford.edu/~afmayer/ https://web.archive.org/web/20060207030527/http://www.stanfo... [2] https://www.sensibleuniverse.net/pages/book.html https://www.sensibleuniverse.net/pages/book.html