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astro123 | 5 years 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.

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dogma1138|5 years ago

It'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.

cbkeller|5 years ago

Vera Rubin would approve. Despite making a lot of the critical rotation rate measurements on spiral galaxies [1,2,3], it seems as though she was never particularly happy with the interpretation of this result as dark matter:

> "If I could have my pick, I would like to learn that Newton's laws must be modified in order to correctly describe gravitational interactions at large distances. That's more appealing than a universe filled with a new kind of sub-nuclear particle." [4]

[1] http://articles.adsabs.harvard.edu/full/1970ApJ...159..379R/...

[2] http://adsabs.harvard.edu/full/1980ApJ...238..471R7

[3] https://www.annualreviews.org/doi/abs/10.1146/annurev.astro....

[4] https://scientificwomen.net/women/rubin-vera-86

ChrisSD|5 years ago

The OP was about how pop-sci reports the paper, not the science itself.

dalbasal|5 years ago

Just 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|5 years ago

That'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.

SubiculumCode|5 years ago

I find this within the sciences also. A lot of the more provocative scientists are willing to be wrong while promoting strong versions of their hypotheses. While this can be criticized as unscientific, I tend to believe that it serves a scientific purpose. Presenting a strong version of a hypothesis pushes people to contend with it, gather empirical evidence, and then incorporate a more moderate version into the idea-sphere.

gh02t|5 years ago

I think OP's point is that pop science reporting is more than "sometimes." Keeping up with controversial theories is fine, often ideas that turn out to be revolutionary are controversial, but it's important not to get a warped perspective about what the broader scientific consensus is.

I know more than one person who has taken it to the extreme, to the point that they latch onto any and every controversial idea seemingly only because it's controversial. That's what you want to avoid.

terravion|5 years ago

It'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-un...

jvanderbot|5 years ago

Specifically: “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.”

im3w1l|5 years 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|5 years ago

I 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|5 years ago

The best suggestion I have is 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!

QuesnayJr|5 years ago

I 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|5 years ago

To 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.

andi999|5 years ago

physicists are usually quite blunt what you call 'fringe' is labeled 'crackpot'

benibela|5 years ago

MiHsC/wuantized inertia would be fringe

throwaway189262|5 years ago

MOND 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|5 years ago

Well, 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.

SiempreViernes|5 years ago

Who 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.

chrispeel|5 years ago

Is 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/...

astro123|5 years ago

The 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.

jinpa_zangpo|5 years ago

ApJ is one of the most respected journals in astronomy.

rpedela|5 years ago

Argument by authority is bad science too.

astro123|5 years ago

No-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...

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.

JamesBarney|5 years ago

Authorities are really useful ways to understand the world.

The vast majority of people would be more correct about the world if they aligned with scientific consensus.

One problem is that journalistic coverage of ideas isn't proportional to beliefs held by experts in that field. Which gives the impression science is constantly changing, and that fringe theories are more widely held than they are.

That's why it's so important for people familiar with the field to help the rest of us who aren't know what "the field considers this a wacky idea".

jhoechtl|5 years ago

Are gravitation and the 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|5 years 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) :

--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.

woodgrainz|5 years ago

Until Dark Matter/Dark Energy theories have been "solved," other theories will continue to exist. That's the way this works.

thaumasiotes|5 years 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"?

Hypx|5 years ago

I 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|5 years ago

From 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.“

anonunivgrad|5 years ago

Scientific 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.

matthewdgreen|5 years ago

While 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.

nl|5 years ago

Scientific consensus is rarely wrong.

There have been 3 major cases in the 20th century that I'm aware of where well-established theories turned out to be wrong.

1) Plate tectonics (dismissed until 1962)

2) The Bohr model of the atom, confirmed by the colours of light absorbed and emitted by ionised helium - which turned out to be wrong

3) The Sommerfeld extension of Bohr's model.

Both (2) and (3) were thought to be correct because they gave predictions correct to 4 decimal places. This turned out to be a co-incidence(!!) and their theories turned out to be wrong and replaced by Dirac's model.

Given the amount of science done in the 20th century, I think that's a pretty good record.

whimsicalism|5 years ago

> Scientific consensus is often wrong.

Often wrong, sure - but still right in the large majority of cases.

plutonorm|5 years ago

The 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!

lvs|5 years ago

Yes, 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!

nwallin|5 years ago

The 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.