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Galaxy Without Any Dark Matter Baffles Astronomers (arstechnica.com)
A distant galaxy that appears completely devoid of dark matter has baffled astronomers and deepened the mystery of the universe's most elusive substance. The Guardian reports: The absence of dark matter from a small patch of sky might appear to be a non-problem, given that astronomers have never directly observed dark matter anywhere. However, most current theories of the universe suggest that everywhere that ordinary matter is found, dark matter ought to be lurking too, making the newly observed galaxy an odd exception. Dark matter's existence is inferred from its gravitational influence on visible objects, which suggests it dominates over ordinary matter by a ratio of 5:1. Some of the clearest evidence comes from tracking stars in the outer regions of galaxies, which consistently appear to be orbiting faster than their escape velocity, the threshold speed at which they ought to break free of the gravitational binds holding them in place and slingshot into space. This suggests there is unseen, but substantial, mass holding stars in orbit. In the Milky Way there is about 30 times more dark matter than normal matter. The latest observations focused on an ultra-diffuse galaxy -- ghostly galaxies that are large but have hardly any stars -- called NGC 1052-DF2. The team tracked the motions of 10 bright star clusters and found that they were traveling way below the velocities expected. The velocities gave an upper estimate for the galactic mass of 400 times lower than expected. The researchers described their discovery in the journal Nature.
... in other ways. I remember reading a paper that explained exactly that away very nicely. I can't find it anymore, but I know it was mentioned in the Scientific American, many years ago.
Our math still does not fit reality, especially energy-wise, but not because of the rotation of galaxies.
It's just that in pop-sci, "dark matter/energy" is commonly presented as if our theories were right and it was just our observations of the universe that are wrong, when in reality, "dark matter/energy" is merely a convenient identifier for the discrepancy and is merely saying "we don't know yet". Implying that, obviously, it's our theories that are still wrong.
So saying "without any dark matter" is already highly questionable. Rather, this galaxy might help us fix our silly theories, to match the cold hard reality that we simply observe. Not the other way around.
The "baffles astronomers" wording is dishonest and disrespectful clickbait bullshit. It is an attack against the reputation of science and scientists. BeauHD should be subjected to disciplinary action for failing to edit this anti-intellectual bigotry out of the headline.
Is this what eventually happens to galaxies, is there a Cepheid variable to tell how old/ how far away the galaxy is? These articles never give enough info... Common for once we common folk may have a chance at understanding the cosmos... :)
[($)]
You are wrong. Dark matter and dark energy are used as they are the only things that help explain our observations of nature.
Yes our theories are still wrong. They will be until we can describe everything - something not likely to ever happen. That's science. What you are doing is hand waving without understanding the basics.
Wouldn't have seen it even if it did.
There are no stupid questions, just stupid people.
I'm surprised your GPS in your cellphone works in spite of your bad science.
Cost free eBook I read (by iBook/Kobo/Amazon/ObookO/Gutenberg etc.): "The Green Odyssey" by Philip Jose Farmer.
I'm more surprised this hasn't happened before. To me I believe it's simple. And YES a BELIEF. Gravity spans dimensions. I am more surprised it hasn't been observed before. My question has always been what does that neutrino look like from a different angle.... It's taken us this long simply to detect them. It is really so hard to postulate particles in other dimensions which we can detect through gravity. It it really so hard to believe that Plato couldn't have been partially right?
If machinery would refuse to work for people who don't correctly understand their working principles, we'd be living in some kind of stone age.
I am not GP, but:
"Dark matter and dark energy are used as they are the only things"
That statement is completely false. "Only" isn't a science word (it requires you disprove all other theories, even theories you haven't had yet), and neither of those claims is proven or even likely, given they don't address even currently understood data.
"hand waving without understanding the basics"
i.e. to paraphrase you make the claim that "dark matter and dark energy" are the basics of science, and that they are set in stone, and deeper understand requires knownledge/acceptance of these basics.
Again this is not science. You will likely have to throw away a lot of theories built on false logic (e.g. QM, standard model, mass/gravity) if the current understanding of these hit a dead end. You cannot say "this theory is broken, yet must form the basis of better theories", because that's nonsense logic. A broken theory is broken, it must be wrong.
"You are wrong"
And acceptance of mistakes is necessary for science, i.e. you might be wrong.
Really the danger to science is people like you. You learn things as though they're true, you build your careers based on this, and when experiments point to faults, you gloss over the failure and defend the broken model. It's more religion than science.
That was the point ... ... how to chissle a stone of several tonns, transport it, erect it, make big structures from it. They had boats, fishing tools etc.
But you somehow twisted it.
People in the stone age already had science
Cost free eBook I read (by iBook/Kobo/Amazon/ObookO/Gutenberg etc.): "The Green Odyssey" by Philip Jose Farmer.
I don't believe that guy is wrong.
Astronomy today is loaded with assumptions. You hear that energy cannot be created nor destroyed, and then in the next sentence say the universe is expanding which means more space, but we know space has vacuum energy, so which is it?
Then we have dark matter is everywhere except in our solar system.
Then we have theories saying the Big Bang created equal amounts of matter and antimatter, but of course we have no antimatter in any meaningful quantity that we know of.
And then you have telescopes finding mature well-formed galaxies 13 billion light years away when the universe was supposed to be in its infancy and shouldn't be there.
We need to put the science back in science, especially astronomy. It is ok to have theories, but to accept popular beliefs as truth is wrong. Probably 20 years string theory fell into that category.
Dark matter is not "proven". It is one possible solution to problems we do not fully understand. Some day in the future, we will hopefully know the answer and it may or may not be dark matter.
It's called White Giant Flight. Even stars want to get the hell away from the darkies. Don't blame them, I would want to raise my young stars in a galaxy full of black holes and brown dwarfs.
You cannot cite the GPS system as proof of the dark matter postulate, its design and implementation did not involve dark matter theory, and he's free to question the validity of dark matter theories while still using Google maps.
The defense of dark matter theory is to show how it explains the new observation already not pretend criticism is luddite stone age thinking.
Consistent observational error works pretty well, too. Quite small errors in the Hubble constant lead to enormous shifts in the established distances of galaxies, and in their sizes. And non-exotic forms of dark matter, such as a higher than predicted percentage of intergalactic planets which are undetectable by current means, also yield quite different orbital structures for large bodies like galaxies.
The exotic "dark matter" proposed by various mathematical models has so far shown nothing that cannot be explained by some very modest measurement or deductive errors. The "extraordinary proof" required for such "extraordinary claims" has never been established.
Well, we are living in a kind of stone age. Just look at the kind of people so-called democracies elect as their leaders (and no, I'm not thinking about Trump only, although he's one of those).
Please, note that there is are some very powerful distinctions between practical engineering and the predictive power of science.
Dark matter has always struck me as a kludge. It amounts to "we don't know WTF is going on, so here's our fudge factor". There is no evidence that dark matter exists, other than the fact that gravity on large scales doesn't behave the way cosmologists expect. Two other possibilities receive too little attention:
- Our current theory of gravity does not apply on the scales we are observing, i.e., the theory is incomplete.
- Physical laws are not constant. e are looking at very distant objects, and seeing them in the distant past. Perhaps universal constants are not, in fact, constant across large spans of space and/or time.
So now they've discovered a galaxy where the kludge factor of dark matter is not needed. Maybe this will prompt more cosmologist to consider the alternatives...
Enjoy life! This is not a dress rehearsal.
And prison guards alike
Yeah.
One wonders what Obama was thinking - "If I give the crazy mullahs in Iran a few hundred billion dollars, they'll STOP trying to build nukes!"
It's so much better to have an Obama-fueled nuclear arms race in the Middle East, right? Because once Iran gets nukes, Saudi Arabia and Egypt won't be far behind...
That'll work out well.
Maybe Obama should have just told the Iranians that there's a "red line" they can't cross....
There are enough unrelated discrepancies in our observations, that can all be explained by dark matter or dark energy (making up a consistent fraction of the universe in all cases), that I think it's safe to say there's probably something to it. Especially when we know the Standard Model in particle physics is flawed, and many extensions happen to contain viable dark matter candidates.
For dark matter specifically, I would say the smoking gun is the aptly named Bullet Cluster. Two galaxies colliding, ordinary matter interacts and gets slowed, dark matter doesn't interact and gets separated from the ordinary matter, and then the dark matter and ordinary matter components can be observed separately (ordinary matter from ordinary photons, dark matter from its gravitational lensing effect on photons coming from galaxies behind the cluster).
Not "the only things that help explain our observations of nature", but rather, "the best things physicists have currently considered that help explain our observations of nature". The OP is right, it's not proven by direct evidence, so it's basically a placeholder for "we don't know, here's a guess of a possibility". The more we do know, the less likely it looks as an explanation, it's just that no better explanation has caught on yet. But in terms of evidence, it's certainly at the gods granted fire to mortals level of explanation. At best, you can say it might be possible. Just because we don't have a better explanation currently, doesn't make dark matter a good explanation. It's not competing with a whole lot. :)
The party of stupid and the party of evil get together and do something both stupid and evil, then call it bipartisan.
Onviously.
In science earth gravity is something like 9.8 at the poles and 9.7 at the equator.
In engineering you simple use a 10.
Oh, that was in meter / sec * sec.
Cost free eBook I read (by iBook/Kobo/Amazon/ObookO/Gutenberg etc.): "The Green Odyssey" by Philip Jose Farmer.
I wonder, did scientists account that perhaps the stars in the outer galaxy are not actually orbiting, but escaping? Wouldn't this also explain the spiral form of the galaxy?
They probably did, using some strange scientific tricks that are beyond me.
Because trying to introduce diplomacy, visibility and thus a small, but very substantial amount of control into this highly sensitive nest of vipers is *exactly* like "If I give the crazy mullahs in Iran a few hundred billion dollars, they'll STOP trying to build nukes!"
Solid thinking there, American. From the South, perchance? Obama is far too intelligent and civilised to be put in front of unwashed Redneck masses. They predictably scream bloody murder any chance they can get their illiterate little paws on. Please just focus on issues more aligned with your own goals and limitations, like, buying and selling weapons, celebrity news, movies and the never ending stream of bullshit sports.
Captcha: superior
Unfortunately "baffles scientists" is a phrase I've come associate with people who use it as a strawman, because there's actually plenty of hypotheses out there. And if they present any of them it's a usually one of the more if not most ridiculous sounding ones. Then they proceed with a false dichotomy by presenting 'maybe it's aliens' with more reasonable sounding arguments than the alleged, opposing position has to offer.
Did anyone try to reclaim the Nobel Peace prize after Obama mugged it from stupid Sweden?
If it was only about rotation speeds, you might have a point. I myself thought e.g. that dark energy alone might explain galaxies not falling apart - empty space exerting pressure, countering tendency of fast moving matter to break loose from gravity pull.
However, dark matter is observed by its gravitational lensing effects, too.
It already walks like a duck AND quacks like a duck.
The only thing that might kill the beast would be if we would find out that galaxies are placed inside bubbles of warped space, where the warping is actually not created by gravity - if there was yet another fundamental force which shapes the spacetime.
Except rotation speeds have already been explained ... in other ways.
But you don't just have to explain rotation curves: you also need to explain the velocity dispersion of elliptical galaxies, mass estimates of galaxies clusters, gravitational lensing patterns, etc. All told, there are at least eleven pieces of evidence for dark matter, of which the galaxy in this story is one: if our theories of gravity, for example, are wrong, and rotation curves should actually look as they do, then why is this galaxy an exception?
"dark matter/energy" is merely a convenient identifier for the discrepancy and is merely saying "we don't know yet"
This is completely correct! But we do know a few things. We know that dark matter must interact with itself a bit, to be able to form small halos - but not too much, so it doesn't condense into black holes. It must move substantially slower than the speed of light (which rules out neutrinos as dark matter) or else the large-scale structure of galaxy filaments, which it seeds, would be more spread out and less lumpy. We know that it must have about five times as much mass as the regular matter in the universe.
The best term I've seen for this is "parameterised ignorance". We know there's *something* there, and we're gradually setting limits on the properties it could have. If a hypothesis predicts a particular set of parameters, and we exclude them, then we throw away that hypothesis. There's still a lot of parameter space left, including a load of hypotheses (plus whatever we haven't thought of) ... but every experiment that chips away at this space brings us closer to pinning it down.
Something that has never been detected wasn't detected...how exactly this news?
Hereis a non paywalled source. This is interesting because it is yet another data point that our understanding of gravitational forces on normal baryonic matter (regular stuff) can hold at at least a few kilo parsecs.
While it's true we don't know if dark matter is an effect, or an actual stuff like wimps (weakly interacting massive particles), the evidence of uniform dispersion from gravitational lensing to kinematics while the uniformity still clumps in a gravitational way is starting to be convincing. A great example is the bullet cluster where the friction of the colliding gasses slowed the normal matter but the dark matter was virtually unaffected, the gravitational attraction was too weak and the dark matter stripped from the baryonic matter. But further, computational models consistent with measurement rely on dark matter to have a cooling effect which wouldn't work (or it's not at all clear anyhow) if it wasn't particle like. If I was a betting man, I'd put my money on a weakly interacting particle.
Given that this looks like a small dense globular cluster emerging from a larger cluster, and its extra bright (probably due to gas shock that started up new stars) it could be shaping up to be bullet cluster #2. link to actual non-paywalled source
*Tadum* *Crash* *Thud* ...
Thank you, thank you, I'm here all week. Tip your waitor and try the fish.
We suffer more in our imagination than in reality. - Seneca
A lot of devices works quite well and are only based on newton mechanics. But GPS on based on Newton mechanics will fail. Newton mechanic is not bad science. It is even very good science and is still a very useful and sufficient model for many phenomenon. But Newton mechanic is unable to predict some observations.
Same here, our theories fail to predict some observations. They work fine for GPS but other phenomenon are not accounted for. Need some other theories, dark matter, never directly observed, is one hypothesis to explain the discrepancies.
No bad science, just science. Reality always win.
This suggests there is unseen, but substantial, mass holding stars in orbit. In the Milky Way there is about 30 times more dark matter than normal matter.
This is an improper statement of what we actually know. It's like saying a UFO must be an alien from another planet while forgetting what the U stands for. We have close to NO IDEA what the phenomena we call dark matter actually is so saying there is 30X as much of it is a nonsensical statement. It could be some sort of matter but we are not at all certain of that. You could say that our current models of gravitation due to matter only explain a few percent of what we see and that would be an accurate statement of what we know. It's possible that the 30X statement is correct but we don't know that yet. If "dark matter" ultimately turns out to be some flaw in the model of general relativity or the like then saying there is 30X as much dark matter as "normal" matter will sound idiotic. If we want to talk in terms of force then fine - saying there is 30X as much gravitational force makes perfect sense.
Short version. We don't know what it is so it's illogical to keep saying how much of it there is until we know what it is.
and he's doing us next!!!!
You don't disconfirm your beliefs much do ya?
A civilization in that galaxy learned how to use dark matter as fuel to create some kind of ftl tech. We are witnessing their decline.
The thing is, our theory of gravity (general relativity) makes a lot of other predictions on scales of the same order, and they seem to work fine.
So do Newtonian mechanics but that was proven to be a useful but incomplete model. Likewise it's hardly inconceivable that there are aspects of gravity not adequately described by general relativity. That doesn't mean general relativity is wrong or useless just like Newtonian mechanics are still useful.
Now obviously it very well could be some sort of matter and there is evidence to suggest that is a reasonable proposition. But until we get more evidence the possibility of it being an error in our mathematical models remains non-zero. I think this fact tends to get dismissed because it's a lot less glamorous than to imagine some sort of exotic matter or new particles. But we've seen it happen before where we invoked fanciful solutions (epicyles anyone?) to explain something that was better explained with an improved model.
The Standard Model is incomplete (there are observations it can't account for), and when extending the standard model in ways to account for those observations, many models wind up including particles that would behave consistently with dark matter.
Exactly. The Standard Model is amazing and highly predictive but we still haven't reconciled it with gravity and we know for a fact that it is incomplete. Therefore it's not at all a stretch to imagine that dark matter is evidence of what the Standard Model is still missing. And that is an exciting prospect. I hope we figure out this mystery during my lifetime.
Do we really know the standard model is flawed? So far itâ(TM)s been stubbornly bullet proof.
does that mean that we're on the dark side? :-)
Ashes to ashes and dust to dust, if the women don't get you the whiskey must
Will you please scrape up the few brain cells you have from the floor?
Please, note that there is are some very powerful distinctions between practical engineering and the predictive power of science.
There are but literally every bit of engineering is based on scientific evidence. Whether or not the person doing the engineering fully and properly understands that science does not make it less true. Engineering doesn't work unless it is based on the ability of science to make predictions. There is science independent of engineering but not the other way around.
People sometimes call engineering "applied science". I think that definition is incomplete. I think it is "applied science with economic and temporal constraints". Engineering is science applied to practical tasks within the constraints of a budget and with a deadline.
Some of us don't give a shit about US politics. 3/10 Meaningless and unengaging, would not be baited by these trolls again.
This could be a confirmation for an alternative hypothesis that dark matter does not exist and that instead the universe has a certain shape (like a donut?) and such which causes galaxies to behave in a certain way.
Because trying to introduce diplomacy, visibility and thus a small, but very substantial amount of control into this highly sensitive nest of vipers is *exactly* like "If I give the crazy mullahs in Iran a few hundred billion dollars, they'll STOP trying to build nukes!"
Solid thinking there, American. From the South, perchance? Obama is far too intelligent and civilised to be put in front of unwashed Redneck masses. They predictably scream bloody murder any chance they can get their illiterate little paws on. Please just focus on issues more aligned with your own goals and limitations, like, buying and selling weapons, celebrity news, movies and the never ending stream of bullshit sports.
Captcha: superior
LOL.
The dumbass who believes letting the Iranians inspect their own nuclear programs for compliance also believes he's superior.
And he stoops to racist stereotypes along the way.
Tell us how an Obama-fueled nuclear arms race in the Middle East of all fucking places is "superior", you utter fool.
Calling you a stupid jackass would be an insult to long-eared equines.
Make Andromeda Great Again! The other galaxies are not sending their best stars. Terrible! Build that beautiful star wall, Mr. NGC 1052-DF2 President!
Except of course your supposed giving hundreds of billions never happened, just more alt right alt facts, otherwise known to anyone with more than one braincell as as lies, because you cant stand the wat the truth contadicts your delusions, you cant even deliver whataboutism convincingly. Sad.
All Iran got was access to their own assets.
That article is all total bullshit, we didn't land on the moon but pretending to see or not to see dark matter...
Maybe it's finally time to shelve your bullshit theory
why did scifi have to can it was good
You can't always tell the idiots that blather on because they lump dark energy and dark matter together.
I'm not a physicist so I can't say for sure how much they are talking out their ass, but in principle you are incorrect.
Always possible but I very much doubt it in this case. What we are calling "dark matter" very plausibly might not actually be matter at all. Until we can actually prove that it is matter or something similar it is improper to say there is X quantity of it.
People figured out how to do basic microbiology to make yogurt, ferment beverages, etc before they had a meaningful idea of what microbes were.
Missing the point. They weren't making claims that it was some mysterious "dark yogurt". They simply shrugged and said they didn't know. "Dark matter" is a placeholder term we use to explain a phenomena in terms of something we think we do understand.
To bring it back to physics, we can have a really model in an equation that matches reality really well without knowing why the constants have the values they do when you run the derivatives and integrals.
Having a model that works does not excuse improperly claiming it describes things you don't fully understand. There is nothing wrong with saying "we don't know yet" instead of saying "there is a bunch of matter we cannot see" when you aren't actually certain it is matter.
Within it's tested limits the standard model is highly accurate. However given that this has been achieved by doing lots of experiments and using them to find some 20 odd constants, so that the model fits the experimental data then that's hardly surprising.
However step outside the tested limits and it's anyone's guess as to whether it's correct or not. Then add in that gravity is absent from the model and clearly at best it is incomplete and incomplete is also "flawed".
All the dark matter in that galaxy. See eg., any Sci-Fi film you care to reference. HTH.
Rotational speeds have been explained rather nicely by other theories, but dark matter/energy has become astronomical doctrine so those better-fitting yet alternate theories get scoffed at.
Rather than posting some sarcastic comment about how respected scientists were sure about luminiferous aether and phlogiston, too, I decided to post something genuine. I studied physics in college. I took the regular undergraduate coursework. I am not a practicing physicist, but I did work on some real physics research projects that went on to get published in respectable journals. Here's my genuine question: if there's so much dark matter out there, why can't we grab some, put in a Petri dish, and start poking it in a lab? Is the science just not there yet?
Take antimatter, for instance. A lot of people might reasonably object to that since we don't see much of it. However, it's possible to make it, see it and - somewhat recently - even to capture it in a magnetic trap and look at it. They can make anti-hydrogen. In a lab, on Earth.
Is there an attempt in the hypothesis to explain why we can't scoop some of this stuff up and look at it? If there's five times as much of it around as there is regular matter, and it doesn't annihilate with regular matter like antimatter, and it has gravity and interacts with regular matter, shouldn't there be some here and some way to get some? Maybe a space probe or something? Would we even know we had any at all if we had less than cosmological quantities of the stuff?
It seems like hand-waving to say there's a bunch of stuff - material stuff - out there that fixes our theories, but we can't get any and wouldn't know if we did. That sounds more like a force behaving differently than we thought, or maybe an equation being slightly off.
Astronomy today is loaded with assumptions. You hear that energy cannot be created nor destroyed, and then in the next sentence say the universe is expanding which means more space, but we know space has vacuum energy, so which is it?
Vacuum energy is a consequence of particles appearing in pairs and annihilating shortly after; there is no net change in energy.
Then we have dark matter is everywhere except in our solar system.
Says who? DM is incredibly hard to detect, assuming it exists at all. The only reason the scientific community is investigating it is because of what happens at galactic scales and larger.
Then we have theories saying the Big Bang created equal amounts of matter and antimatter, but of course we have no antimatter in any meaningful quantity that we know of.
CP violation is a thing we can't adequately explain yet, granted, but the difference between the amounts of matter/antimatter created is tiny.
And then you have telescopes finding mature well-formed galaxies 13 billion light years away when the universe was supposed to be in its infancy and shouldn't be there.
That's because the expansion of the universe isn't limited to the speed of light. Duh.
We need to put the science back in science, especially astronomy. It is ok to have theories, but to accept popular beliefs as truth is wrong. Probably 20 years string theory fell into that category.
If anyone needs a fresh infusion of real science here, it's you.
Dark matter is not "proven". It is one possible solution to problems we do not fully understand. Some day in the future, we will hopefully know the answer and it may or may not be dark matter.
Well, at least you got one thing right.
Maybe that galaxy exported all their dark matter to China in exchange for clean coal.
I'll see your senator, and I'll raise you two judges.
This is such a fucking shitty headline. This is why there are accusations of FAKE NEWS. Shitty fucking so-called "Journalist" over-hyping every goddamn thing. A more appropriate headline is, "Galaxy without Dark Matter PUZZLES Astronomers". They are not fucking BAFFLED. They CURIOUS.
You so-called college education isn't worth the shit on the toilet paper I wiped my ass with last night. You and your so-called "Journalism Professors" should all be dumped in a whole after a bullet is put into your brain pan. The world would be a better place.
Fucking worthless pricks!
And prison guards alike
Yeah.
One wonders what Obama was thinking - "If I give the crazy mullahs in Iran a few hundred billion dollars, they'll STOP trying to build nukes!"
It's so much better to have an Obama-fueled nuclear arms race in the Middle East, right? Because once Iran gets nukes, Saudi Arabia and Egypt won't be far behind...
That'll work out well.
Maybe Obama should have just told the Iranians that there's a "red line" they can't cross....
Maybe if the United States hadn't overthrown the democratically elected government in Iran to benefit its oil companies, they wouldn't now be dealing with an Iran aspiring to nuclear weapons. Over the past 50 years the US has shown that the way to avoid having your government overthrown is to get nuclear weapons. It is a rational response to the US effecting "regime change" anywhere they damn well feel like it.
Americans are really quite amazing. They interfere with other countries the world over, for decades, and are then completely mystified when that world reacts to it. Americans have no idea who they really are.
EDIT: Correcting my typos...
This is such a fucking shitty headline. This is why there are accusations of FAKE NEWS. Shitty fucking so-called "Journalist" over-hyping every goddamn thing. A more appropriate headline is, "Galaxy without Dark Matter PUZZLES Astronomers". They are not fucking BAFFLED. They are fucking CURIOUS.
Your so-called college education isn't worth the shit on the toilet paper I wiped my ass with last night. You and your so-called "Journalism Professors" should all be dumped in a hole after a bullet is put into your brain pan. The world would be a better place.
Fucking worthless pricks!
Anonymous coward trolls who get their info from 4chan/pol or the work at the INTERNET REEEARCH AGENCY themselves are so cute. Don't fall for this bullshit, go read about the Iran deal from a credible source.
You don't even have your facts straight and this rhetoric is retarded. D I A F.
Wow, the retards have plenty of mod points today.
Which "dark matter candidates" specifically? The Standard Model? No (obviously). String Theory? Where are SUSY and WIMPS? SUSY is nowhere to be seen at CERN. M-Theory? Bah.
There's an awful lot of bollocks out there masquerading as science. Beyond the Standard Model and Relativity, which we assume to be correct, we have no viable hypothesis.
...go read about the Iran deal from a credible source.
Here's Shepard Smith with a short, informative run-down on Uranium One.
Forgive my ignorance, I'm not that into astronomy or physics, but is it possible these stars appear to be moving faster than they should because the universe is expanding?
I've always read about expansion in terms of red shift and distance between galaxies, but what about the space within galaxies? Isn't that expanding too?
Rotational speeds have been explained rather nicely by other theories, but dark matter/energy has become astronomical doctrine so those better-fitting yet alternate theories get scoffed at.
Can you give a RECENT example of another theory that explains rotational speeds and doesn't contradict any other observations?
Does it also explain ANY of the other things that Dark Matter explains?
Quack. Believing is easy when it's for entertainment. But for science we need a theory that predicts the results, and belief has no place in that. Easy or hard doesn't even apply
The other theories to explain rotational speeds don't account for other things dark matter does. It was first hypothesized as a solution to galactic rotation, as I remember, but there's been plenty of other confirmation coming in. Something we can't detect by other means is creating gravitational fields.
"When you have eliminated the unacceptable, whatever is left, however improbable, must be the truthiness" - Holmes
That's technology not science.
Science is a specific (and very important) technology. It a specific method for determining what ideas are true based on active observation of nature (experiments).
You don't have to use the scientific method to gain knowledge about the world. However most otehr methods have proven to work considerably worse in practice.
Don't make me laugh. Do you actually expect me to believe that clean coal exists?
Who's modding this site - a bunch of MAGAtards? Since when is blatant racism modded up?
The Iranians were internally inspecting their own nuclear program BEFORE the deal. The difference is that, the Iran deal lets OUR inspectors monitor their work as well. Without the JCPOC we would have no idea what they were up to. It helps to have at least basic understanding of a subject before you go attacking people about it on the internet. There is no "Obama-fueled nuclear arms race in the Middle East", it doesn't exist except in your head. Before the deal, and before Obama there were countries in the Middle East who would have loved to get nuclear weapons. After the deal, there are still other countries in the Middle East who would love to have nukes, but Iran is demonstrably and verifiably NOT perusing nuclear weapons technology anymore. That is an improvement over the previous situation by far.
I call a Point Of Order on ancient yogurt makers.
"They simply shrugged and said they didn't know." No they did not! It was called a "yogurt culture" long before microbes were known about. Similarly, the principle of disease transmission was widely known and (near) universally accepted, long before the germ theory of disease existed.
What you are essentially saying is that ancient peoples didn't know everything, and therefore they didn't (and couldn't) know anything. This is wrong. They clearly understood that there was something in the yogurt, that something spread, and the something was needed to make any new yogurt. In other words you inoculated milk with an existing yogurt culture to make new batches of yogurt.
It was a supposition (though a reasonable supposition) that the "something" in yogurt was alive. Why? Because if you cooked it, the yogurt making process was stopped cold, and would not restart. Also, you could permanently halt the yogurt transformation by adding various substances understood to be lethal to humans and animals. And of course milk is food for humans and animals, so it could plausibly be food to the mystery yogurt essence.
An alternative explanation (to yogurt cultures being alive) would be that the yogurt transformation was catalytic in nature. While reasonable, catalytic reactions are uncommon. Thus this explanation falls afoul of Occams Razor. It also doesn't really explain why cooking yogurt kills the allegedly catalytic reaction, (poisoning a catalyst is a real thing though).
I read TFA on Ars Technica and you have it backwards, this finding may actually rule out MOND, which is what I think you are referring to when you mention the alternative method to explain rotation curves:
The answers were pretty surprising. The data on the 10 globular clusters the team tracked showed them moving much more slowly than would be expected. That led to an estimated mass that was extremely low for a galaxy—on the order of 10^8 solar masses. Using the amount of light emitted by the galaxy produced an estimate of the total mass of stars in the galaxy that was also in the neighborhood of 10^8. Normally, we infer that there's dark matter around because the galaxy appears to have a lot more matter than the amount provided by the stars we can see. But in this case, there's a minimal difference between the two...
"Paradoxically, the existence of NGC1052–DF2 may falsify alternatives to dark matter," the authors conclude, noting that those alternatives include both variations of MOND and emergent gravity.
So this galaxy rotates like we would expect galaxies without much dark matter to rotate, unlike most other galaxies we see. If MOND were right, we shouldn't see galaxies this bright that rotate this slowly.
It doesn't matter how beautiful your theory is, it doesn't matter how smart you are. If it doesn't agree with experiment [ed, observation in this case], it's wrong.
--Richard P. Feynman
... in other ways. I remember reading a paper that explained exactly that away very nicely.
You are wrong and a troll. At best, those that are attempting a modified theory of gravity have come up with a theory to explain galactic roate in 2D, not 3, and completely misses any other observations such as gravitational lensing.
So saying "without any dark matter" is already highly questionable. Rather, this galaxy might help us fix our silly theories, to match the cold hard reality that we simply observe. Not the other way around.
From TFA: "It turns out that a galaxy without dark matter is incompatible with models that replace it using modified gravity. Since there's some normal matter here, any version of modified gravity would have that matter produce dark-matter-like effects. We don't see any indication of these effects, so modified gravity ideas must be wrong.
"Paradoxically, the existence of NGC1052–DF2 may falsify alternatives to dark matter," the authors conclude, noting that those alternatives include both variations of MOND and emergent gravity."
As the Bullet Cluster was supposed to be the thing that proved the dark matter model, this is even more so as offering proof that other theories can't even begin to explain these observations.
You hear that energy cannot be created nor destroyed, and then in the next sentence say the universe is expanding which means more space, but we know space has vacuum energy, so which is it
Both. The total energy in the Universe is ~0. We assume perfectly zero, but we only know to some decimal place of precision. Everything we see is both something and nothing at the same time. Energy in an of itself is nothing. It's the potential of the energy that allows something to exist or work to be done. Vacuum energy cannot be tapped as an energy source because there is no gradient.
The expansion of space is removing net energy. It's creating more total energy, but that energy is useless. At some point objects are moving away so far and fast that we can no longer interact with them, which means the potential to interact has been removed and now potential energy is reduced. There's also energy being lost in the sense of the CMB redshifting.
A vast increase in gross energy with a loss of net energy. It all averages out to nothing.
LIGO ruled out MOND about 6 months ago. Shot it strait in the head. If MOND was real, the gravity waves would have been different. Since we saw the explosion, we knew how far away and all that. Unless another gravity wave reading casts doubt on the accuracy of this last reading, MOND cannot be raised from the dead.
Dark matter and dark energy are used as they are the only things that help explain our observations of nature.
"God did it" is just as logically sound (same exact reasoning of theory over observation) and it has less holes. Dark matter/energy are variables we threw into equations to make them mostly fit curves. Not only do the equations still fail to fit the curves, but now we have a bunch of variables with no observable basis in reality that we don't know what they are - chances are the equation itself is in the wrong format, not that there are some random variables sprinkled through it we have no indication actually exist save for the result of the equation we're working backwards from. That said, if it actually doesn't exist somewhere and that somewhere doesn't align with something obvious (galactic center, motion through space, some nearby bodies, etc) then chances are this could be the first proof of dark matter - if it does align with one of those then chances are we can finally eliminate dark matter from the equations and revise them appropriately.
I suspect it REALLy baffles Cosmetologists
Dunno why, but I always thought the observable effects of what gave the creation of dark matter was always the near massless photons.
near zero mass over the shear size of the universe adds up.
The spirit of resistance to government is so valuable on certain occasions that I wish it to be always kept alive
It's all really funny when one knows the real answer.
Tesla was right and Einstein was wrong. Gravity is nothing but magnetism. Once you accept this, all of the anomalies and paradoxes resolve.
So the one thing I take away from this is that scientists really do not have a convincing working model for current observed cosmological gravitation behaviors. This reminds me of a different time when scientists seemed to have no working theory. Back in the late nineteenth century, scientists were trying to explain how the sun generated so much energy. When you did calculations based on energy outputs from standard chemical reactions, the maximum possible output for the sun was computed to be orders of magnitude less than the actual output. It was not until nuclear fusion was properly understood in the twentieth century that an adequate theory was put together that could explain the sun's energy output.
We are again at a scenario where predicted models say there should be a lot less of a something, and we are trying to stitch in theories to try to explain how there is so much more of the something than expected. And if you believe that scientists are unhappy about this, then you do not know scientists. A baffled scientist is an excited scientist.
The poster is talking about STARS, not humans.
But for science we need a theory that predicts the results, and belief has no place in that.
I believe everything I know. I don't know everything I believe. Look up "believe".
He's getting rather old, but he's a good mouse.
Yes, I expect you to believe it. Our great orange leader said so.
I'll see your senator, and I'll raise you two judges.
That stuff we don't know what it is? Well we've discovered a galaxy that doesn't have that stuff. Although we don't even know if it is stuff.
So what we don't know is missing locally, if indeed it exists at all. Which is unknown.
Looks like maybe the aliens in that galaxy figured out dark matter was really a fuel source (a la Futurama) and went and burnt it all up.
You could say the same thing about quarks and leptons. They're things scientists made up to explain things. Apparently, we can never see a quark in isolation.
"God did it" is crap science, in that it closes off investigation. "We don't currently know how it works" is scientific, and invites further investigation. So far, no reformulation of equations explains what black matter explains. Physicists have tried all sorts of theories, and dark matter is clearly the most promising.
"When you have eliminated the unacceptable, whatever is left, however improbable, must be the truthiness" - Holmes
Explain? How does postulating stuff with weird properties EXPLAIN anything?
Dark matter is far from the most promising, it's only presented that way by pop-sci entertainers like Nye, Tyson, and Kaku.
Engineering has worked despite nobody in the world knowing the underlying science.
What is your point? Even pure science doesn't have a perfect grasp of the world so I'm not really sure where you are going with your argument. Science is at its core a method of investigation rather than a body of knowledge. The body of knowledge that results is a second order effect of the process. Engineering IS a branch of science because it follows the scientific method. It would not work if it did not. One does not have to have a conscious awareness of what the scientific method is to follow the scientific method.
You can make a bridge by trial and error, and that's pretty much how engineering worked for most of its existence.
Trial and error is still science as long as you learn from the errors. You form a hypothesis (design a bridge), perform an experiment to test it (build a bridge), and refine your model based on the results (did it fall down?) and repeat the experiment as necessary. That is science in it's most basic form. Understanding every last detail of what is going on is not required for the process to follow the scientific method.
Engineering is the art of applying science.
Engineering IS science. It is the practical application of the scientific method to a real world problem resulting in a product or process. Calling it an "art" really doesn't accurately describe what is going on because the term "art" is so vague as to be effectively meaningless in this context.
As thought, it can be independent of resource constraints (money and time).
If it is just a thought experiment then it isn't engineering. Engineering always results in a tangible product or process. Thought experiments are just theoretical physics or math. It doesn't become engineering until you actually build something to test the solution. Engineering is NEVER independent of resource constraints (time, money, labor, and/or materials).
It's the only promising. All of the other ideas thus far have been falsified. There are others in the works, but not many remaining as entire classes of hypothesis', like MOND, have been proven fundamentally incompatible with recent observations in the past 6 months. I am not sure about the idea of "emergence", but I know some claim this may have also been fundamentally proven false by similar observations against MOND.
Aether theory has never been disproven, quite the contrary. Morley continued aether experiments after the famous failed one, what he showed between the combination of them is that there is an aether and it is the source of inertia (the failed experiment tested for a static aether which we moved through, testing for a drag, his follow-up experiments tested for a dynamic aether which moved with us.) Morley was able to induce motion in the aether and detect it as an observed change in the speed of light, but this was largely ignored due to the popularity of relativity (in spite of being used in the engineering of modern optical gyroscopes, and more recently in the theory behind the initial version of the EM Drive [though indirectly, since the EM Drive was derived from an aetheric interpretation of the function of the optical gyroscope, which has an alternative explanation in standard physics incapable of explaining the EM Drive test results.]) The big problem with the original aether theory interpretation is actually obvious in retrospect: if it induced drag everything would stop (akin to the pre-Newton concept of the universe naturally sucking energy out of everything.) Instead, the aether as the source of inertia also happily explains why light slows down in materials and not in vacuum, without relying on some idiotic non-inductive effect (light spontaneously slowing down in a medium other than vacuum then speeding up outside, without significant scattering in either, is an absolute absurdity in the context of particles so long as conservation of energy exists, but as an inductive effect it is readily explained with a simple rate of induction in both cases.) Similarly, under aether theory the electron isn't an actual particle, but a point at which inertia discharges while photons are the circuit between emission and absorption of longitudinal disturbances of the aether (which when measured appear to be transverse in nature due to the topological effects involved in 3 dimensional space with Buckminster Fuller describing this in terms of a quantum gravity based on the 3 dimensional tetrahedral grid naturally generated by sticking enough self-interacting energy into a volume [aka, by two conjugate inductive forces such as dielectricity and magnetism, which we term electricity when together.]) The particle interpretation is absurd on its face because particles are an emergent effect of the transient levels at which forces balance out at a given time (which itself is more an emergent effect of length-limited Rindler horizons in an infinite multiverse composed of infinite dimensions where matter exists in 3 simply because it's the only number of dimensions in which you can tie a knot, which itself has been proven in a topological context.)
TL;DR: There's a lot of good experiments and observations after Relativity, but Relativity itself was a curve ball that fucked all of physics, Minkowski didn't even believe it was right and that's why he threw it to Einstein to have him publish it (Relativity itself being Minkowski's interpretation of the combined works mostly of Poincare and Lorentz - which itself was based on a misinterpretation brought about by Heaviside when he refactored Maxwell's original 20 equations in quaternion form into 4 in vector calculus form, happily dropping the scalar components deeming them unnecessary in the process simply to make the equations easier to work with. The fact of the matter is the scalar components describe those levels of interactions at which emergent particles come to exist (or rather, the current level at which that happens) and describe a sort of inertial field which extends through different modes into dielectric, magnetic, weak, strong, and gravitational fields - the fact they're everywhere is what makes them scalar but that doesn't mean you can just eliminate them from the equations outside of very specific contexts (though those very specific contexts describe just about everything we have engineered to date with modern physics, save for oddities like the optical gyroscope which was more happenstance it correlated correctly with reality and some of Tesla's work, which was based on aether theory itself.)
For the tl;dr crowd, this is a proposal that we discard all of non-quantum physics for roughly the past century, and reformulate everything on the basis of single experiments with the luminiferous aether. For the record, I fail to see why this approach is promising.
"When you have eliminated the unacceptable, whatever is left, however improbable, must be the truthiness" - Holmes
It doesn't involve throwing away the past century's observations. It's promising because we've hit a dead-end where we can't reconcile GR/SR with quantum mechanics and instead rely on fudge factors like dark matter, dark energy, dark flow, etc to explain it away without observation. One of the two or both, if not outright wrong, is at least failing to account for the whole picture. When that happens while working on anything else you revert to the last thing without issues and go from there, not keep hacking logical fallacies into it with the hope they balance out. We disgarded aether theory because a single experiment which was interpreted incorrectly, not because any observation refuted it - that makes it an infinitely better choice than SR/GR or QM. Aether theory has yet to contradict a single observation.
Okay, let's see aether theory on galactic rotation curves, gravitational lensing, time flow like on GPS satellites, observed expansion of the Universe, etc. I assume it can explain all of those. If not, it hasn't contradicted an observation because it hasn't been tested.
Special and General Relativity have been very well tested over the years. Any replacement theory has to agree with them almost precisely over a very large range of conditions, much like relativity relates to Newtonian mechanics.
Dark Matter stopped being a fudge factor a long time ago. It explains a large number of different phenomena.
"When you have eliminated the unacceptable, whatever is left, however improbable, must be the truthiness" - Holmes
Yes, it does explain them because it uses the exact same equations (the aether specific stuff only comes into play when dealing with the scalar components of Maxwell's original quaternion-form equations which Heaviside dropped.) Einstein plagiarized relativity from Lorentz (the critical part to the aether based on Maxwell's work) and Poincare while using Minkowski's interpretation of the two for the theoretical scaffolding. Relativity is just a contextually-restricted subset of aether theory. Add the scalar components back in and dark matter isn't needed.
[Luminiferous] Aether theory has never been disproven
What? I'm Petty sure it was decapitated when the speed of light was shown to be the same in all direction as the Earth orbits the Sun. One of the predictions of Luminiferous Aether is a universal frame of reference for light, making it slower or faster depending on which direction you're moving, fundamentally incompatible with Relativity. Seems quantum vacuum is classified as a form of "Aether", but is definitely not Luminiferous Aether.
You're referring to the idea of a static aether we move through and experience drag from, the follow-up experiments Morley did proved the existence of a relativistic aether with strong hints that it is the source of inertia, as I described already. The static aether was a dumb concept, that's the variation the Michelson-morley experiment disproved and is incompatible with subsequent observations.
Einstein is responsible for Special Relativity, not the mathematics of it. He made the mental leap so daring that it was controversial for decades afterwards, despite the evidence. Had Poincare realized what the math was telling him, it would have been Poincare's Theory of Relativity, and it isn't.
So, how do the scalar components account for galactic rotation, movement of galaxies in clusters, mass distribution in a galactic collision, the gravitational lensing observed in various places, the cosmic microwave background, or the fact that QM considerations say that there wasn't enough normal matter formed in the Big Bang to account for all the gravity?
"When you have eliminated the unacceptable, whatever is left, however improbable, must be the truthiness" - Holmes
Minkowski is responsible for SR, Einstein was his lacky and he passed it off to him because he didn't want to tarnish his own name due to the controversial nature of it (there are letters between the two of them which have since been published indicating as much.)
The scalar components constitute exactly what we would call a "field" today, but the issue is more where they break down over different scales (not as sharp cutoffs, but the rate of decay changes so radically they might as well be.) It's all one force, including electricity, magnetism, gravity, the strong force, the weak force, and infinitely more over different scales we haven't even probed yet - the scales of that force and the modes of travel are what we end up calling many difference forces (since a true scalar field doesn't actually exist when you remove time from the equations and replace it all by distances and magnitudes.) The Heaviside interpretation Lorentz did his work on was a scale-limited version confined to what we're calling the electroweak force now.
With dielectricity you get magnetism and gravity due to the mode of propagation, which also explains the differences in strength we can get out of the two from the same amount of matter (it spirals out to infinity from a point around the dielectric inertial plane and comes back from an infinite distance in all directions as a hyperboloid stretched to infinity.) When you are very close to that spiral (the hyperboloid that is, the dielectric inertial plane is 2 dimensional and is very hard to get an interaction out of) you can see two separate poles because of the similar rotations (they are spinning the same way as they spiral back in, but depending which side you are looking at that will be clockwise or counter-clockwise,) when those poles lock together you get magnetic attraction and when they move in the same direction so that they can't lock together you get repulsion. It's that spiral of inertia which generates space and time, which are really just the repulsion of a bunch of point sources in 2D, tying themselves into infinite knots in 3D (topologically you can only tie a knot in 3 dimensions using a string-like entity, so while there are likely infinite dimensions and infinite universes, we see one with 3, over which we have time because a 3-dimensional frame is just static.) At larger scales where you don't have that high angular velocity of the dielectricity you get gravity because all of the dielectric lines of force (not actual lines because they are going in all directions at once, but easier to visualize that way) appear to be going in approximately the same direction (toward the massive body, because that 2D dielectric plane interacts very weakly with the 3D universe we observe.) At super-small scales like with the strong force you can get more of a net effect between the faucet-like dielectric inertial planes and the sink-like hyperboloids because they aren't actually point-like (they're close, but all that energy rushing back into the sink gives a sort of expansion to the hole [for lack of a better word] it is rushing back into,) so the dielectric inertial plane has a much larger target it can hit (remember, it's pushing outward and creating spacetime in the process, if it has say 5% [arbitrary number, I've never tried to calculate that part, it's likely more closely related to a ratio of phi, e, or pi - which are all infinite series which represent geometrical modes of decay during inductive and counter-inductive processes] which immediately gets sucked into what is for all intents and purposes a void, then you effectively have an attractive force equal to the force that particle is exerting on the universe to create new space over that angle.) Now think back to the hyperboloid and the dielectric inertial plane and what those two shapes would do when set into a natural configuration: it would form a tetrahedral grid. Buckminster Fuller actually calculated this out based on the concept of a bunch of energy packed into a tight space resulting in the quantum foam
I think your use of "wrong" is a pretty strong word.
As I understand it, our current theories don't explain the amount of mass of various very large bodies in the universe. To counter this folks have come up with "dark matter" and "dark energy" to explain it away as something we cannot yet observe. I myself thought it silly that there was a report of something missing this. What is interesting is that there is a discrepancy. I wonder how closely it meets our current understanding, in that it's mass is about what we actually think the math should tell us. I've also seen articles that talk about dust and gas, which because are so dispersed over such a vast amount of space are for all intents not very observable, but in all could explain the inconsistency. Though I have also heard that it is not enough to account for it.
Anyway I've never liked the terms "dark" as I thought it was just a cop-out for things not lining up like you think it should. I don't call that science. That said this stuff falls into the realm of theoretical physics which has always had issues with observability and confirmation, sometimes which take many years for either technology or unique phenomenon to catch up on like that very large gravity wave we had a little while ago (relatively speaking)...