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I only skimmed the paper past the abstract, but for what it is worth. The MOND favouring group is a fringe of the cosmology community. The vast majority feel t
by astro123 6y ago
I only skimmed the paper past the abstract, but for what it is worth.
The MOND favouring group is a fringe of the cosmology community. The vast majority feel that there is enough evidence to rule it out.
I mostly mention this because I don't like that fact that popular science magazines (or at least their content that I see posted here!) has a bias towards "new and possibly exciting" or "controversial" research. Which I understand - revolution is more interesting that "physicist reduces error bars by 50%. Big picture unchanged". But, if all you read is these articles, you will get a very skewed idea of what the consensus is.
Just so there is no confusion, modified gravity as an explanation for Dark Energy is very possible, as an explanation for Dark Matter, the consensus is that it is ruled out.
Edit: I clarified my point below but will do it here too so everyone see it. I don't have a problem with this paper, I'm glad people are writing papers with alternate explanations to the consensus, that is how science is done. But, your conclusion from reading this article shouldn't be, "ahh damn, I guess MOND is right and LCDM is wrong" and I think that is how pop-sci articles tend to frame these things.
- chrispeel 6y agoIs the journal that the paper [1] is published in also fringe? Or not refereed? [1] https://iopscience.iop.org/article/10.3847/1538-4357/abbb96/meta https://iopscience.iop.org/article/10.3847/1538-4357/abbb96/...
- astro123 6y agoThe astrophysics journal (ApJ) is a really good journal. A majority of good astronomy papers are published in ApJ or in MNRAS. Big things go in Nature/Science + then there are other smaller journals. (At least this is what I tend to find. This may just reflect my biases - US based, in the cosmology field.) But just because something gets published doesn't mean it is right :) I think non-scientists don't know what "peer review" actually entails! First, as this was a MOND paper, it could well have been reviewed by someone who favours MOND. Second, even if the reviewer doesn't favour MOND, if the steps taken and the arguments given seem reasonable, I expect they would suggest it should be published. I have no issue with the paper being published. It is important that theories have advocates who put forward the best argument for them. What I do take issue with is the skewed presentation in popular science. What sells is exciting and new, not slow and steady. And 99% of science is slow and steady.
- ngoldbaum 6y agoAlso, peer review in astronomy generally consists of correspondence with a single reviewer. There may be multiple rounds of review but a significant majority of papers submitted by professional astronomers doing serious research to journals are ultimately published. It is not the norm in astronomy to be rejected outright from a top journal and then submit to a lower tier journal, instead almost everyone publishes in a few popular journals. This is a tradeoff, but definitely in astronomy at least this means some iffy papers are ultimately published, even in ApJ, and you must always be aware when reading the literature that the paper you are reading is not infallibly correct just because it was published in a journal.
- jinpa_zangpo 6y agoApJ is one of the most respected journals in astronomy.
- rpedela 6y agoArgument by authority is bad science too.
- astro123 6y agoNo-one is making an argument by authority. Here is a nice popular article that outlines some of the issues with MOND https://www.forbes.com/sites/startswithabang/2018/03/06/only-dark-matter-and-not-modified-gravity-can-explain-the-universe https://www.forbes.com/sites/startswithabang/2018/03/06/only... I just think that it is very hard to understand the scientific consensus (average view of people who spend a lot of time thinking about this) when all you read are popular science articles that tend to focus on the exciting/new/possibly game changing edges. I'm just here letting people know what the consensus is.
- rpedela 6y agoMost people on HN are aware that the consensus, a form of argument by authority, is dark matter. It is also known that the dark matter consensus has problems despite billions spent on research over decades. When there is an experimental result that contradicts the leading theory, that is interesting and worthy of media attention. If this experimental result was only published in popular media, then I too would likely ignore it. However it was also published in a major journal. Like you said elsewhere, that doesn't mean it is right. But I think it is worthy of attention and discussion and should not be dismissed out of hand because it doesn't agree with consensus.
- dodobirdlord 6y agoThe existence of a consensus opinion isn’t an argument from authority. To claim so is an interesting form of the post hoc ergo propter hoc fallacy ('after this, therefore because of this'). The argument for agreeing with the consensus isn’t the existence of the consensus, but rather the same argument that caused the consensus to exist, the underlying body of research. Framing it as a result that flies in the face of consensus is fun and exciting, especially since people who are science-literate know that a single compelling result can overturn a consensus formed by a large body of previous work. But framing it in that sense is unhelpful, since the vast majority of publications that “fly in the face of consensus” do not. It’s a lot less exciting to view this as one more paper on a large pile supporting MOND, that is still small in comparison to the pile that support dark matter. The paper is obviously worthy of attention and isn’t being dismissed out of hand, it is published in The Astrophysical Journal. But would Hacker News be discussing it if not for the contrarianism embodied by the former framing, as opposed to the latter?
- QuesnayJr 6y agoI think physicists throw around the word "fringe" too easily. Most physicists think that MOND is not true, but "fringe" implies that the physicists who advocate for it are wackos, like they're Young Earth Creationists or something.
- vlovich123 6y agoTo me fringe means has little support but still in the realm of science. In other words little support but not yet disproven. Young earth creationism isn’t valid science and thus doesn’t even share the same reality let alone being on the fringe of reality.
- astro123 6y agoYup, by fringe I meant "On the edge of what reasonable people are working on". But maybe it's not a great term if people misunderstand.
- andi999 6y agophysicists are usually quite blunt what you call 'fringe' is labeled 'crackpot'
- benibela 6y agoMiHsC/wuantized inertia would be fringe
- terravion 6y agoIt's true the LCDM is the consensus, so this result is even stronger from an outsider's perspective since the lead author apparently comes from the LCDM community, not the MOND community. https://scitechdaily.com/what-if-dark-matter-doesnt-exist-unique-prediction-of-modified-gravity-challenges-dark-matter-hypothesis/ https://scitechdaily.com/what-if-dark-matter-doesnt-exist-un...
- jvanderbot 6y agoSpecifically: “I have been working under the hypothesis that dark matter exists, so this result really surprised me,” Chae said. “Initially, I was reluctant to interpret our own results in favor of MOND. But now I cannot deny the fact that the results as they stand clearly support MOND rather than the dark matter hypothesis.”
- dalbasal 6y agoJust to play devil's advocate... sometimes a little spectacle is OK. A lot of these ideas really are "new and exciting." Science just moves at a slower pace than media. It's not a monthly. By exaggerating the pace they're.. uhm... bridging the gap or something. Controversy is even more engaging than novelty. Maybe a pop science article gets you sucked into the pre-clovis camp of a paleoanthropology controversy. Now you are engaged in paleoanthropology. Three years later, a possibly butchered snake skeleton is found and you go "aha! I was right! They ate snake soup! Clovis people didn't even like snake!" It's a little cheap, but it's also fun. Why not. People enjoy having opinions. No one loves sports without having a favourite team, strong opinions regarding training schedules and sports rehabilitation practices... an occasional gamble. Most know that they're not really experts, but they enjoy being in the fray nonetheless. Pop science magazines aren't supposed to be textbooks or encyclopedias. We are fortunate to have wikipedia for that. Give me a little sauce, a little clickbait. I might not always admit to it... but sugar tastes good.
- astro123 6y agoThat's a fair point. I love reading computer hardware rumours, most of which are probably total garbage (and probably obviously so to anyone in the field). And in this case, whether the general public thinks the universe in MOND or LCDM really doesn't matter at all. My real issue is when this reporting is on things where the general public's opinion does matter. Things that the general public might vote on. Economics, medicine, etc. Having seen this type of reporting in a field that I do know something about (and a field where there is no real incentive to mislead, again MOND vs LCDM, who cares), I'm a lot more distrustful of science reporting in fields I don't know much about (and where there are incentives to mislead). If they had published the article exactly as is, giving you all the excitement, but just added a single line somewhere saying "this is new work that is up against a large body of previous work that points in the opposite direction. Let's see what happens, but its a cool idea" I'd be totally fine with it.
- matt_kantor 6y agoThe final sentence of the linked article is this: > But it’s important to keep in mind that so far the bulk of the evidence still points towards dark matter, and it’ll take much more work to topple that hypothesis entirely.
- im3w1l 6y ago> mostly mention this because I don't like that fact that popular science magazines (or at least their content that I see posted here!) has a bias towards "new and possibly exciting" or "controversial" research. Which I understand - revolution is more interesting that "physicist reduces error bars by 50%. Big picture unchanged". But, if all you read is these articles, you will get a very skewed idea of what the consensus is. I stopped reading popsci mags for this reason. But I do feel like I'm missing out too. Do you know of any good mags that mostly talk about mainstream stuff, but targeted towards "I studied some of that in college but I don't work in the field"?
- coldpie 6y agoI think Ars Technica does a pretty great job of science reporting without being over the top. It's not a magazine, but the weekly podcast The Skeptic's Guide to the Universe also covers interesting science topics in a balanced manner.
- astro123 6y agoThe best suggestion I have is https://astrobites.org/ https://astrobites.org/ These are paper summaries, written by people in the field, where you are probably the target audience. I don't read it myself, but give it a go!
- dogma1138 6y agoIt's seems that the authors of the paper all come from the LCDM/Dark Matter observational testing community, this isn't a paper by MOND theorists. They were quite likely looking for evidence of dark matter with the ESO survey and found something else. Right or wrong, this is the definition of good science.
- ChrisSD 6y agoThe OP was about how pop-sci reports the paper, not the science itself.
- bosswipe 6y agoWhich is a boring meta criticism that adds nothing.
- philosopher1234 6y agoI didn’t find it boring or useless. I found it quite interesting. No need to be so negative bosswipe
- bosswipe 6y agoThe other comment threads in here are discussing the actual experiment and theories. But this thread is at the top taking up a bunch of the oxygen and it's just repeating tired old media criticisms that we've all heard before. The actual experiment is way more interesting.
- anonunivgrad 6y agoScientific consensus is often wrong. Science advances one funeral at a time. Most “scientists” are conformists looking for their next grant. Outside of the tenured professor elite, most of them are looking for the next job. And the tenured are just one step higher on the pyramid, motivated by prestige and admiration, not pure motives. There’s nothing wrong with that, it’s called being human. But don’t put too much stock in consensus, because many of the great breakthroughs have been ignored and ridiculed before finally being accepted.
- plutonorm 6y agoThe most insightful comment is buried at the bottom of the list. Two kinds of people in this world, those who think truth lies where the crowd is and those who think it's where the crowd isn't. The conformists won't see the blindingly obvious until it knocks them over. Unfortunately the genes that make us good for a farming society make us a little sheep like ourselves. Here's to the hunters who've struggled through this far into the age of the farmer! cheers!
- matthewdgreen 6y agoWhile it's fun to criticize science this way, this line of criticism misses an important fact: namely that open scientific inquiry has been one of the most successful enterprises in the history of humanity. In a period of a few hundred years we've gone from believing that there were a few basic elements and that the sun revolves around the earth, to understanding the deep nature of particle physics and the structure of the Universe. We turned a basic understanding of chemistry into an understanding of subatomic particles, and the ability to create entirely new elements. We did all of this through a process of open and skeptical inquiry, which has been remarkably consistent in its ability to tear down unsupportable theories. The reason the Kuhnian critique exists is not because the scientific process failed, it's because the process worked but just took longer than people expected it to because people are human and imperfect. And the speed of scientific advances over the past decades has been higher than at any point in human existence. The reason the term "scientific consensus" exists is because most fields are vastly too complex for a single human being to be able to evaluate the totality of the evidence by themselves, at least in a reliable way. So the process is necessarily decentralized and broken up among many experts, who share their opinions. This isn't some popularity contest that you should ignore, it's a critically necessary task that has to be performed in order to digest the research contributions of any field, and make progress on solving open problems. You're absolutely right to point out that consensus evaluation can malfunction sometimes. You'd be equally right to point out that sometimes experimenters produce invalid results. You're wrong that the answer to the former is to reflexively ignore the scientific consensus process, just as you'd be wrong to say that "don't do experiments anymore" is the correct response to a few experimental errors.
- lvs 6y agoYes, except the evidence for dark matter is really an absense of evidence. So "new and exciting" in that context isn't some grand transgression. There's no experimentally supported theory of dark matter to transgress!
- willis936 6y agoThe job of astrophysicists is to make models that explain observation. Explain the bullet cluster observations. https://en.wikipedia.org/wiki/Bullet_Cluster https://en.wikipedia.org/wiki/Bullet_Cluster
- sharpneli 6y agohttp://backreaction.blogspot.com/2017/01/the-bullet-cluster-as-evidence-against.html http://backreaction.blogspot.com/2017/01/the-bullet-cluster-... And same thing applies to LCDM. How does it explain bullet cluster, and several others, existing in the first place? Disclaimer: I'm not a cosmologist even if I do have a background in physics. I do like following the field. It's just not quite so clear as you imply. And if we go into things like superfluid dark matter then it doesn't really matter if its dark matter or some kind of modified gravity. One has bunch of equations and what matters is how they behave.
- nwallin 6y agoThe evidence that dark matter is particulate in nature that obeys the gravitational force, but not the strong nuclear force or electromagnetic force does have actual direct evidence for it. The other poster has alluded to the bullet cluster. The bullet cluster is a pair of colliding galaxies. We can measure the distribution of gravitational lensing in a region of space, and in doing so, indirectly measure the mass distribution. We can directly measure the light output of colliding gas clouds in the two galaxies. We can measure the distribution of stars within them. Analysis of this data shows us that dark matter has momentum. This tells us that if you want to reformulate dark matter in terms of a modification of variations of F = Gm1m2 / r^2 you'll need to do some really ... interesting things. On the other hand, we know neutrinos have mass, do not interact via the strong nuclear force, and do not interact via the electromagnetic force. We either have to assume really, really ugly math in order to give a fundamental force a momentum, or we can assume there are new particles that are sorta like neutrinos but different. There are other problems that I don't fully understand. Apparently MOND is very, very difficult to reconcile with the rest of known theory if the speed of gravitational waves travel at the speed of light. Which the 2017 neutron star merger taught us that they do.
- Moodles 6y agoHere a scientist was so sick of the journalist bias towards sensationalism that he trolled the international media into reporting that chocolate helps you lose weight. Sample size n = 4. https://www.npr.org/sections/thesalt/2015/05/28/410313446/why-a-journalist-scammed-the-media-into-spreading-bad-chocolate-science https://www.npr.org/sections/thesalt/2015/05/28/410313446/wh...
- woodgrainz 6y agoUntil Dark Matter/Dark Energy theories have been "solved," other theories will continue to exist. That's the way this works.
- sieabahlpark 6y ago> I mostly mention this because I don't like that fact that popular science magazines (or at least their content that I see posted here!) has a bias towards "new and possibly exciting" or "controversial" research. You'd rather have a homogenized science magazine that has predetermined what is and isn't correct? You could alternatively not consume, purchase, or share any articles relating to the magazine. Having a bias isn't a problem. Having a bias and saying you don't is always a problem because no one, under any circumstance, is unbiased.
- Hypx 6y agoI think the bigger issue is that LCDM has no produced much fruit in the last several years. Despite many attempts to detect it, no one has found anything. Furthermore, the main motivation for LCDM was super-symmetry, but the latter has also failed to produce much evidence in favor of it. There comes a point where the consensus view is no longer seen as the most plausible explanation. This does necessary mean something crazy like modified gravity is true, but rather that there could be a better theory out there. However, in order to find that better theory all avenues need to be explored.
- what2build 6y agoFrom the bottom of the article: “It’s an intriguing result, and it may lend some weight to the MOND hypothesis for further study. But it’s important to keep in mind that so far the bulk of the evidence still points towards dark matter, and it’ll take much more work to topple that hypothesis entirely.“
- thaumasiotes 6y ago> Just so there is no confusion, modified gravity as an explanation for Dark Energy is very possible, as an explanation for Dark Matter, the consensus is that it is ruled out. How could you possibly rule out the theory that "the rules are different over there, somehow"?
- throwaway189262 6y agoMOND may be a fringe but wholesale support of Dark Matter by mainstream physics has always seemed cargo culty to me. Over a hundred years and we still don't have a good understanding of dark matter. A red flag to me is how there doesn't seem to be large amounts of dark matter in areas closest to us where we can see best. It's all this far off enigma. And at least originally the theory existed to explain why the laws of gravitation didn't line up with visual evidence. To me "half the matter is invisible" is just as outlandish as "maybe our math is wrong about gravitation". I don't think enough of the community questions the dark matter theory.
- mnl 6y agoWell, maybe the thing is you just don't know anything about it. Current dark matter concepts are 40 years old, not over a hundred (again, Wikipedia is not a substitute for an education). And we have detected indeed a very common kind of actual dark matter, predicted 26 years before you could "see" it simply because it explained the data, we call it neutrinos. The universe is brimming with cold neutrinos btw. Everything seems outlandish from a prejudiced superficial POV.
- dash2 6y agoThis comment could reduce the snark (to zero) and still be just as informative.
- mnl 6y agoProbably, but then HN commenters could reduce this tendency of stating that whole scientific disciplines don't know what they're doing/are full of deluded morons. Particularly when it comes to physics. At some point you have to mention the other possibility.
- SiempreViernes 6y agoWho gave you the idea that it's over a hundred years old? The solid results are from the 70's, while a hundred years ago it was still an open question if galaxies really existed... Not sure what you mean with there not being any dark matter (DM) in our neighbourhood, the DM content of the Large Magellantic Cloud is estimated to outweigh the visual matter by a factor of 4, and the LMC is right up in our face.
- jhoechtl 6y agoAre gravitation and the Fine-structure constant https://en.wikipedia.org/wiki/Fine-structure_constant https://en.wikipedia.org/wiki/Fine-structure_constant related? I am absolutely no physicist but if yes: The Fine-structure constant has been discussed that it is not a constant but slightly varies in the observable universe. Would make no wonder, if gravitation is related to the fine-structure constant, that gravitation varies too.
- noetic_techy 6y ago>> the consensus is that it is ruled out Science does not work by consensus opinion. I know many non-scienctists and even some scientists get pissed when you say this but it is the absolute truth and true to the scientific method. This idea that the "consensus" has ruled out all other theories for a substance that we cannot even detect is an appeal to authority logical fallacies and a bias towards a known flawed paradigm. Authorities who have never detected Dark Matter say it cannot possibly be anything other then Dark Matter. Thomas Kuhns The Structure of Scientific Revolutions details this mentality that leads to these sort of errors in thinking, which can be summarized as follows (taken from an outline of his book found here: https://www.uky.edu/~eushe2/Pajares/Kuhn.html https://www.uky.edu/~eushe2/Pajares/Kuhn.html) : --Students study these paradigms in order to become members of the particular scientific community in which they will later practice. ----Because the student largely learns from and is mentored by researchers "who learned the bases of their field from the same concrete models", there is seldom disagreement over fundamentals. ----Men whose research is based on shared paradigms are committed to the same rules and standards for scientific practice. ----A shared commitment to a paradigm ensures that its practitioners engage in the paradigmatic observations that its own paradigm can do most to explain, i.e., investigate the kinds of research questions to which their own theories can most easily provide answers. Even the author of this paper is an LCDM (AKA dark matter exists) advocate who had to admit that his preference does not fit the data observed: "I have been working under the hypothesis that dark matter exists, so this result really surprised me,” Chae said. “Initially, I was reluctant to interpret our own results in favor of MOND. But now I cannot deny the fact that the results as they stand clearly support MOND rather than the dark matter hypothesis.” The keyword there is "reluctance". This sort of mentality ripe with internal bias towards the existing paradigm is the number one thing that I think holds back scientific progress. The breakthroughs that push things forward rarely come from the consensus holders and those simply doing research that refines the current paradigm. Dark matter / Dark energy has never been detected / sourced - and the by the way the Standard Model of physics IS DEFINITELY WRONG and does not explain all observations. It simply our best approximation just like Newtonian Mechanics was, but we need to look beyond it rather then be scared to defy it.