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.
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.
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.
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.
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.
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.
> 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.
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.
> 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]
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.
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.
> I can find no evidence or even remote hints of his connection to anything you have listed
It took a while, but I think I found the PDF of the book I was talking about [0].
> fundamentally you are making an ad hominem argument, effectively saying, "this guy is a crackpot, why should we listen to him?"
Kinda, not really. I'm saying that if my recollection is correct this guy has expressed wild ideas before that were also ignored by the physics community and therefore it is worth viewing his works with suspicion because we are not qualified to evaluate it, but people who are have apparently decided it wasn't worth much.
> 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.
Sure, admittedly. So, why aren't any physicists giving this idea the time of day?
As I was pretty clear about in my post, I do not consider myself (nor you) qualified to assess his work in anything more than an armchair manner. The fact that his ideas don't seem to be something other physicists take seriously is something of an indicator that maybe I shouldn't either.
> 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
Because we are not physicists, as I assume you aren't either. Go to a forum full of physicists if you want a real assessment of its worth. We, being not physicists ourselves, can only judge its merit by proxy and intuition. The latter of those is especially dubious and especially prone to liking simple, elegant, compelling, and utterly wrong ideas.
> 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.
Strong words for someone who's response to all of this is "watch the video and you'll understand". Hand wave indeed.
> I think I found the PDF of the book I was talking about
Thank you for taking the time. My search fu is admittedly weak. That you've consumed this is also impressive.
> So, why aren't any physicists giving this idea the time of day?
Bandwagon.
> As I was pretty clear about in my post, I do not consider myself (nor you) qualified to assess his work in anything more than an armchair manner.
Ad hominem.
> Strong words for someone who's response to all of this is "watch the video and you'll understand". Hand wave indeed.
First, recognize the fallacies you're employing.
The video lecture and slides use high school level Newtonian physics to explain galaxy rotation clusters. If you understood the physics in his book, the physics in the video should be child's play. It is not remotely difficult to understand. And it is possible for a layman to evaluate it for rigor without referring to the theorist or other physicists.
> Thank you for taking the time. My search fu is admittedly weak. That you've consumed this is also impressive.
It was years ago, and I only gleaned the high concept really, but it has been around for nearly two decades now (though mysteriously not mentioned at all by Mayer's site) and, you will note, makes some pretty big claims about the fundamental nature of the cosmos including the ones I mentioned.
> Bandwagon.
Hand waving. You say that others are not doing the work by looking at the video you posted yet insist on this dismissive justification for ignoring that the qualified professional physicists of the world don't seem to think Mayer has accomplished what he claims.
> Ad hominem.
Hand waving, and wrong. I'm not insulting you, I'm pointing out the facts: we are not qualified to give an informed appraisal of this material. Drawing conclusions about its validity because it makes sense to us is pretty much exactly the Dunning-Kruger effect.
Look at what you're saying: somehow this guy has explained galactic rotation curves with high school level physics while practically all other physicists over the last nearly a century clung to some obviously wrong idea instead? And your explanation for this is that they're all in a bandwagon? This is the same community that said high-temperature superconductors couldn't exist, and then someone proved them wrong and won the fastest nobel prize in history.
Please explain how that is even remotely a rational conclusion, because it sounds like the same level of discourse one gets from flat earth conspiracy theorists.
Frankly, the idea that you are arguing in good faith is becoming harder to believe.
> You say that others are not doing the work by looking at the video you posted yet insist on this dismissive justification for ignoring that the qualified professional physicists of the world don't seem to think Mayer has accomplished what he claims.
No, I was identifying your argument, made again after I already identified it, as a bandwagon fallacy.
> Hand waving, and wrong. I'm not insulting you, I'm pointing out the facts
I did not suggest there was insult, only that you were employing the ad hominem fallacy by ignoring the material and focusing on me and you. Any argument focusing on anyone's expertise, in this case mine and yours, is entirely irrelevant and fundamentally an ad hominem argument, which is necessarily fallacious.
> And your explanation for this is that they're all in a bandwagon?
No. Your's and pfdietz's argument, paraphrasing, "if it's correct or worth our time, why hasn't the physics community acknowledged it?" or whatever, is fundamentally a bandwagon argument, which is fallacious.
You're right that what I'm saying about our level of expertise says nothing about the validity of Mayer's assertion, but what you can't seem to grasp is that even if I did watch the video, and even if I did understand everything it was saying and that made total sense to me, that doesn't mean that his assertion is valid because I'm not qualified in the appropriate domain.
When you're not actually well versed in a domain, all sorts of completely simple, elegant, compelling, and utterly wrong ideas make sense. I couldn't find any fault with The Many Directions of Time, but that doesn't mean it is a good model of cosmology[0], it's just the result of me not really understanding the domain sufficiently. It is completely rational to doubt my judgement under these circumstances.
Therefore, knowing that I lack the ability to judge the work's validity, I employ a heuristic: do people who are qualified to judge it say it is valid? And the answer appears to be "they don't even consider it worth their time to look at", which I find to be particularly strong evidence that I shouldn't take it seriously either.
The alternative is employing my own flawed understanding to judge validity, which is of course going to produce garbage results.
As a proponent of this idea, you have asserted that you think it is valid, and despite not disagreeing with the assertion that you yourself are not a domain expert, continue to assert that because you understand it, it is valid. You are free to believe that all you wish, of course, but it isn't going to sway any of us. Especially when, heuristically, the things you're saying are a close match the language employed by conspiracy theorists, flat earthers, and the like.
If your goal is not to convince us... then what is the point of this discussion?
If your goal is to convince us, I'm telling you that you're doing a particularly unimpressive job of making your case by refusing to engage with the heuristic reasoning in any way, or even offering an alternative other than "watch the video and it will convince you". I will note that watching a video of a conman or magician can be pretty convincing too, so that's not exactly good evidence either.
If what you're trying to say is to trust in scientific method, then we still can't trust our own reasoning with the argument and need to rely on the objective analysis of others including testing of hypothesis... none of which has happened. If it had, I'm sure you'd have brought it up by now.
So, again, this all heuristically looks like bullshit. We have a supposed "one neat trick solves one of the most mysterious things in modern physics" that, unsurprisingly, "physicists don't want you to know about" or whatever, and the resident proponent of the concept refuses to do anything but point people at the source video they aren't qualified to objectively analyze, and said proponent refuses to explain why it all looks like bullshit even if it supposedly isn't.
Since we seem to be miscommunication to a significant degree, I will try and summarize this:
-Mayer has an idea that looks compelling to laymen
-The experts in cosmology have apparently not even bothered to engage with it
-While this does not mean Mayer is wrong, for those of us who are not experts in cosmology it certainly looks like we shouldn't take it seriously
-You're asking us to ignore that and pretend that our layperson judgement is somehow good enough
[0] It might be, but again the heuristics are against it for the same reasons.
> that doesn't mean that his assertion is valid because I'm not qualified in the appropriate domain.
You are very eloquently and thoroughly attempting to justify your ad hominem argument, and to be more specific, you are presenting a credentials fallacy.
Let's assume for the sake of argument that I am an expert, and more so, that I am more qualified to evaluate the lecture than any scientist that ever lived or ever will live, and I tell you, it is correct, and I know, because I'm an expert, then regardless whether I or the presentation is correct or not, I'd be committing an appeal to authority and a fallacious argument.
Regardless of whether you are an expert in physics or not has no bearing on the validity of the theory, nor whether you are capable of deciding whether the theory is valid or not. You've speculated whether I was arguing in good faith, and now I must do the same. You're obviously intelligent and capable of deep consideration. Either you watch the video and draw your own conclusions, or you can not speak to it. It is that simple. Do or do not, those are your only choices. There is no valid argument that you can make to weasel out of them.
