Dark Matter Grows Hair Around Stars and Planets (forbes.com)

StartsWithABang writes: Dark matter may make up 27% of the Universe's energy density, compared to just 5% of normal (atomic) matter, but in our Solar System, it's notoriously sparse. In particular, there's just a nanogram's worth per cubic kilometer, which makes the fact that we've never directly detected it seem inevitable. But recent work has demonstrated that Earth and all the planets leave a "wake" of dark matter where the density is enhanced by a billion times or more. Time to go put those dark matter detectors where they belong: in the path of these dark matter hairs.

Comments

The dark matter between their ears

[Anonymous Coward]

Dark matter must exist, because if it doesn't, it means we have been wrong all these years!

Remember, when the facts don't match your theory, too bad for the facts. The theory is easily explained by an abundant (making up 96% of the universe), invisible, undetectable magic "dark mater" that is everywhere and affects everything. We just can't see it or detect it, you see, but it's totally there. Just like phlogiston and aether.

Re:The dark matter between their ears

[Anonymous Coward]

So your theory is that our current list of known particles is complete. Why is that likely, given that we've discovered new particles quite often in the last 100 years?

Re:The dark matter between their ears

[Maritz]

Force of gravity falls away at inverse square. Stars in outer edges of galaxy rotate much too fast, given the visible matter. You forgot to include your explanation for this. While you're at it, explain the bullet cluster. Cheers.

Re:The dark matter between their ears

[AC-x]

Hey nitwit, the theory of dark matter is only there because of the facts. We call it dark matter because we don't know what it is, but we can see it's there.

Re:The dark matter between their ears

[Anonymous Coward]

Ockham's razor: The facts suggest that gravitational force without visible source is being exerted.

Since the only known source of gravity we know is matter, we assume that gravitational source comes from some invisible matter, but we don't currently have any solid proofs for this specific assertion (although neither do we have any to the contrary, nor alternate viable theories).

It may yet appear that it does not. It may be some form of existence different than matter or energy; some wrinkles of spacetime or some sourceless gravity clusters. Since we don't know anything like that, "dark matter" is a convenient shorthand to describe that effect.

It's a bit like both with Rutheford's atom model and with Planck's quantization of spectrum.

The first - assuming that atom structure is a kind of "dough" with electrons being "raisins" fit the knowledge of that time explaining the "solid" nature of solids. It was blatantly wrong, proven by later experiments that found tiny nuclei in huge empty space. It was still a convenient shorthand for a time, to describe several observed phenomena and fit some observations - and for lack of better alternatives, it was accepted until disproven.

The latter sounded so incredible at first, that it was used strictly as a *hack* to obtain results that fit the experimental data, with belief that the underlying mechanism is vastly different, but undiscovered as of yet - so the "hack" was again a shorthand used to explain given phenomena, out of convenience, because again, we didn't know any better way to explain the behavior of photon emissions, or the stability of atom - even though practically nobody believed it to be true, just a conveniently close approximation. And then, surprise-surprise, more and more experiments confirmed - that "hack" was actually how the reality worked, that was not a mistake but a very unlikely - though ultimately true - description of the nature of atom.

Whether Dark Matter is another Rutheford's Atom, or another Planck's Quantum distribution, is to be determined and it will either be confirmed or invalidated. Currently, as a shorthand explaining the observed phenomena, it's doing pretty well.

Re:The dark matter between their ears

[locofungus]

Remember, when the facts don't match your theory

Correct. The facts don't match the theory. Galaxies could not hang together the way they do if all they consist of is the things we've already observed in the laboratory unless we change the law of gravity [to something enormously more complex - c.f. epicycles] or postulate the existence of something that interacts gravitationally but doesn't interact with light.

too bad for the facts

I don't get this. Nobody is ignoring the facts. That's why we need to change things. Dark matter is the heliocentric solution. No dark matter is the epicyclic solution.

The [difference between facts and] theory is easily explained

Don't know about easily. There's been a lot of "dark matter" theories that have fallen due to one or more inconsistencies with known physics.

by an abundant (making up 96% of the universe),

Necessary otherwise we have to change the theory of gravity

invisible,

If by invisible you mean doesn't interact with EM radiation then yes, this is required by the facts.

undetectable

It's not undetectable. If it were undetectable then we wouldn't need it. It's very detectable - its gravity is what makes galaxies hang together. Its gravity is what allows gravitational lensing to happen where there isn't any (visible) matter to make it happen.

magic

Definitely not magic. It has to agree with all the laws of physics. Conservation of momemtum, conservation of energy, speed of light etc.

"dark matter"

it's called dark matter because it doesn't interact with the EM spectrum. It neither emits EM radiation nor absorbs it.

that is everywhere and affects everything.

Actually, I think this is one of the great unknowns. Whether it's large numbers of light particles or smaller numbers of massive particles. Its primary interaction with the known universe is through gravity which yes, does affect everything, everywhere, at the speed of light.

Re:The dark matter between their ears

[Anonymous Coward]

Or maybe - if the current theory of gravity doesn't explain that phenomenon - the theory is wrong?

Nah, it must be a magic invisible thing that somehow fills the entire universe in a 20-1 ratio to regular matter which we've never seen or detected but know it's there because if it isn't we'll lose our grant money and it'll be obvious we can't tell our butts from a hole in the ground and have been lying for the past 70 years. This is what professional con men do, not scientists.

Re:The dark matter between their ears

[Anonymous Coward]

I don't have to provide alternative explanation to point out that what I see here is an ungrounded assertion. They're trying to manipulate facts to match the theory, not the other way around like actual scientists do.

Re:The dark matter between their ears

[Anonymous Coward]

no they aren't. they have observations that don't match the math calculations and they are trying to account for it. just like right before the theory of relativity. they thought there was and extra planet due to unexplained observations in the orbit of the planets that didn't match the math

Re:The dark matter between their ears

[PaulMattSutter]

Dark matter isn't a case of "fact vs. theory", but "fact vs. fact". We have multiple methods of determining the mass of galaxies and galaxy clusters. One method - counting all the light-emitting stuff - gives a certain number, and all other methods (rotation curves, gas kinematics, gravitational lensing, large-scale structure analysis, and more) give a much higher number. Two possible conclusions: 1) Our understanding of gravity is wrong, or 2) There is a new component of the universe that does not interact with light. Option 1) fails a lot of tests: if you try to make solutions for gravity for certain systems, it doesn't work for others. Option 2) has a solution called "dark matter", a new weakly-interacting massive particle that explains almost all the observations (it's not 100% perfect, but it does much better than the changing-gravity option).

At the same time that all this was happening in cosmology, our particle physics friends were developing extensions to the Standard Model. In many theories they predicted new kinds of particle: ones that just happened to have a lot of the right kind of properties that the cosmologists needed for dark matter. Voila.

Dark matter is the simplest, most parsimonious, most elegant known solution that fits the observational data.

Source: I'm an astrophysicist and I do a podcast, and one of my first episodes was on exactly this.

Re:The dark matter between their ears

[Yoda222]

Saying that there exist some non-baryonic matter is a theory. So they have fact (observations) and they manipulate the theory (by adding dark matter, dark energy to barionic matter to the model) to match the fact. Exactly what you were asking for. But if you have an alternate model to offer, go ahead, I'm sure astrophysicists would like to hear from it.

Re:The dark matter between their ears

[Anonymous Coward]

So which facts are being contradicted/manipulated? Care to provide any experiment results that disprove the theory?

Re:The dark matter between their ears

[SharpFang]

Maybe it is. Suggest a better alternative though. We're sticking to this one as long as we don't have any better.

Re:The dark matter between their ears

[Anonymous Coward]

Well, bring up an alternative that explains everything PLUS what DM does, BUT BETTER. ***THAT*** is how you do science, not just go "Oh, pooh, it's wrong. Prove me incorrect!".

GRAVITY is a "magical invisible thing". MASS is a "magical invisible thing", if all you're going to do is call something "magical invisible thing", then what the fuck are you standing on this frigging planet for? FLY AWAY. Because magical invisible things can't prevent you doing it, can it.

Re: The dark matter between their ears

[Anonymous Coward]

No, we can't see that it's there. All we see are gravitational perturbations. For all we know it could be space-leprechauns.

Re:The dark matter between their ears

[Maritz]

Wrong. Galactic rotation curves do not match with what is predicted by Newton or Einstein. The outer stars are orbiting much too fast. You either explain it with hidden matter, or you explain it by modifying gravity. The the fact in this case is the anomalous rotation rates. I suggest you need to look again into what 'actual' scientists do, because what they don't do is ignore interesting observations.

Re:The dark matter between their ears

[gtall]

Ah, so your argument is that because he doesn't have an adequate theory to replace yours, your flea bitten theory must prevail.

I don't know what the right theory is either, and neither do you. Attributing the extra gravity phenomenon to dark matter is nothing more than a variation on the G-d-of-the-Gaps. Got a problem with gravity, Dark Matter. You could give the alien guy Georgio with the electric hair a run for his money.

Re:The dark matter between their ears

[Bengie]

You have that backwards. They're modifying theory to match the facts. They've tried to ignore darkmatter for nearly 100 years, but they can't get rid of it. The more information we get, the more real it becomes. It has reached a point in science where the numbers are slapping us in the face, saying, "STOP IGNORING ME!"

Re:The dark matter between their ears

[Maritz]

Not really. It's either hidden gravitating material or Einstein's theory needs to be modified. The former is more likely than the latter. I'm not emotionally invested as to which is right, unlike you.

Re:The dark matter between their ears

[Anonymous Coward]

MoND comes to mind...
 
It works in places that dark matter does and doesn't in places that dark matter does. I'm guessing we're going to find a few facts along the way (in the form of physical phenomena on the relativistic level) that are going to make every competing theory we hold up today flawed.
 
So maybe you could have brought up the science instead of being a snide little cuss.

Re:The dark matter between their ears

[MightyMartian]

They're not manipulating anything. They are observing that there are numerous objects which appear to have a lot more mass than is visible. Unless you think there is something wrong with our Classical view of gravity, then the obvious answer is that there is a lot more matter out there than we can directly observe.

Fucking hell, there's nothing worse than some self-appointed anonymous poster on the Internet who is some fucking arrogant and stupid that he thinks he understands something better than the scientists. And why is it that such arrogant fucktards always end up on /, trying to make themselves look oh so smart.

Re:The dark matter between their ears

[xxxJonBoyxxx]

>> why is it that such arrogant fucktards always end up on /,

I for one welcome our SlashComma overlords.

Re:The dark matter between their ears

[Tim the Gecko]

Attributing the extra gravity phenomenon to dark matter is nothing more than a variation on the G-d-of-the-Gaps. Got a problem with gravity, Dark Matter.

For more than two decades you could have written:

Got a problem with beta decay energy conservation, "neutrinos".

Even as invisible particles, they were the best explanation on the table to explain beta decay. Then they got detected as well.

Re:The dark matter between their ears

[Anonymous Coward]

So inventing a non existent planets to "patch" shoddy math is good science? Your answer turned out to be incorrect? Just change the question!

They keep insisting dark matter is a thing despite my entire lifetime worth of searching for what is reported to be 50% of the mass of the universe? That's not fudging things to make orbits match, that's HALF the entire universe.

Not saying they are wrong per se, but it would be exceedingly good if investigating alternatives to such an outlandish theory wasn't left mostly to the lunatic fringe.

Re:The dark matter between their ears

[Anonymous Coward]

Not that there couldn't be some unknown force exerting gravitational effects on mater throughout the universe but the "facts" you are talking about are based on long distance observations of various EM radiation (viable light, infrared, microwave, etc) observed over hundreds, thousands and sometimes millions of light years. We have NO idea how these phenomenon could be effected over such insane distances. We're like bacteria on an apple observing jets 40,000 ft above us and assuming that out observations within a few feet of the tree somehow prepare us for understanding the conditions that the jet is experiencing. Those bacteria wouldn't know a thing about altitude pressure changes, jet streams, thermal differentials or any number of other effects which would throw off their observations and render their theories on what they're seeing obscenely incorrect. Not saying we shouldn't try to explain what we see, but history has shown that we are most likely going to be wildly incorrect without DIRECT observations (IE being there) not a bunch of guesswork based on massively incomplete and possibly corrupt information.

Re:The dark matter between their ears

[Anonymous Coward]

Saying that there exist some non-baryonic matter is a theory.

No, it is a hypothesis. A Theory is a complete [yet capable of improvements], predictive body of knowledge.

Relativity is a Theory. Superstrings is a hypothesis.

Re:The dark matter between their ears

[Anonymous Coward]

Because without that, you're "MoND" is NO different to space pixies. IF MoND were true, there would be a different modifier for newtonian dynamics for each galaxy, and MoND doesn't explain at all the gravitational lensing.

No, saying "MoND!" is no different than saying "GOD DID IT!".

Specify what modification and why and provide the evidence that supports that modification, and any evidence that doesn't.

You know, proper science, not the armchair stuff.

https://www.quora.com/What-is-the-current-thought-on-the-MOND-theory

Re:The dark matter between their ears

[Applehu Akbar]

"Remember, when the facts don't match your theory, too bad for the facts."

Our phlogiston-powered probe will find out how those dark matter hairs interact with the luminiferous aether through which our solar system is passing.

Re:The dark matter between their ears

[Anonymous Coward]

Unless you think there is something wrong with our Classical view of gravity,

I think that his point is exactly this, if the data doesn't match the model, then the model is probably wrong. That is, perhaps rather than some mystical imperceptible substance that doesn't exist locally (for reasons?), what if there is some element we are neglecting (for instance, if we only observe this is distant objects, perhaps gravity was stronger in the past than it is now for some reason).

I'm obviously spit-balling, I don't have any data to back up my claim that there is a time-dependent component to gravity.

Re:The dark matter between their ears

[Anonymous Coward]

Hey nitwit, the hypothesis of dark matter is only there because of the facts. We call it dark matter because we don't know what it is, but we can see it's there.

FTFY

Re:The dark matter between their ears

[Fire_Wraith]

It strikes me somewhat as the discovery of the planets, including Neptune, and the theoretical, but ultimately nonexistent, planet Vulcan.

The planet Neptune was identified not by visual observation, but by mathematical calculation based on errors in the predicted orbit of Uranus. Something was causing changes in the orbit Uranus should have taken according to the Newtonian model, and what was missing was another planet. They then were able to predict where it would be, and later observations by telescope confirmed that.

Thus when Mercury's orbit could not be accurately matched to the Newtonian model, one of those same 19th century astronomers theorized that there must be another planet between Mercury and the Sun, which was dubbed "Vulcan," that would account for the missing aspects of the equation. It was only much later that Einstein's theory of relativity correctly and accurately accounted for the inconsistencies without any hypothetical planet between Mercury and the Sun.

All of this isn't to say that "Dark Matter" is wrong or inaccurate, more just to illustrate how things operate with a known scientific model. If you have a missing variable, it may mean that there's something else you're not seeing through other means involved, or it may mean your model is wrong. The way you test that though is to come up with, and test/observe for, those things.

Re:The dark matter between their ears

[AthanasiusKircher]

unless we change the law of gravity [to something enormously more complex - c.f. epicycles]... No dark matter is the epicyclic solution.

I completely agree with your post. However, I really wish people would stop using the "epicycle" as something to denote ridiculous complexity.

The reduction of epicycles is NOT what drove the Scientific Revolution. Some facts:

- Medieval astronomers did NOT add "epicycles on epicycles." Owen Gingerich, one of the foremost historians of science and perhaps the world's greatest expert on Copernicus has spent nearly 50 years trying to stamp out this myth, which seems (according to him) to have originated with some ignorant writings in the early 1800s which had no clue how the earlier astronomical systems worked. If people actually understand how the system works and how the tables medieval astronomers used were constructed, everyone would easily comprehend why it wouldn't have been basically impossible (in a practical computational sense) for medieval astronomers to add "epicycles on epicycles," even if they wanted to.

- Even if medieval astronomers wanted to do this, they simply didn't make the required number of observations necessary to construct such a system. And even if they did the observations, their models of the sky weren't accurate enough to do the sorts of measurements necessary to see planetary position error. (The only way they could tell planetary position was in reference to the fixed stars, but those experienced precession over the centuries and Ptolemy's model of precession was screwed up and had inaccurate medieval corrections thrown in... that didn't exactly work well.) Bottom line: even if they wanted to measure planets with greater accuracy to construct such a system, they couldn't.

- The main reason why anyone got interested in these problems in the 1500s is because there were a few observations where Mars was REALLY out of whack (like 5-6 degrees) with the original Ptolemaic predictions. which happened at conjunctions. Copernicus was driven toward his system after one of these "Martian disasters." Tycho Brahe did observations of the same periodic problem in 1593, which probably led him to tell Kepler to work on the Mars problem.

- Copernicus did NOT eliminate epicycles. In fact, as he tried to make his system more accurate, he actually ended up introducing MORE epicycles than the standard Ptolemaic model.

- Kepler's greatest move toward greater accuracy was achieved by use of old Ptolemaic idea of equants to offset the earth's position around the sun correctly, which produced a MAJOR improvement in predictions, even still using the old epicycle model. The need for epicycles was finally abolished with Kepler's adoption of elliptical orbits, but this correction was much smaller, perhaps only about 1/10th of the improvement in accuracy compared to Kepler's previous advances still assuming the equant/deferent/epicycle models.

TL;DR: Epicycles were good "science" that more than adequately fit the data for ancient and medieval astronomers. Nobody was putting MORE epicycles in to make corrections to the old model, except arguably Copernicus himself. Nobody thought of replacing the old Ptolemaic model until people started doing enough observations to notice a real problem, and after that solutions were proposed almost immediately. And the improvement Kepler made by finally getting rid of epicycles was REALLY small (comparatively), especially seen in contrast to the corrections introduced by adopting heliocentrism and displacing the earth's orbit (both of which were still done in the old geometric system which required epicycles).

So, the modern practice of using "epicycles" as derogatory parlance for a bad, overly complex model doesn't make much sense.

But don't listen to me. You can listen to Owen Gingerich himself describe what he calls

Re:The dark matter between their ears

[Anonymous Coward]

" Option 2) has a solution called "dark matter", a new weakly-interacting massive particle that explains almost all the observations (it's not 100% perfect, but it does much better than the changing-gravity option). "

Of course it explains all observations, because it was conjured out of thin air to do exactly that. Since it hasn't been observed, all of its properties were made up to explain what otherwise would be a deficiency in the current theory of gravity.

Re:The dark matter between their ears

[aristotle-dude]

Wrong. Galactic rotation curves do not match with what is predicted by Newton or Einstein. The outer stars are orbiting much too fast. You either explain it with hidden matter, or you explain it by modifying gravity. The the fact in this case is the anomalous rotation rates. I suggest you need to look again into what 'actual' scientists do, because what they don't do is ignore interesting observations.

Or perhaps scientists don't have a clue how gravity works on a large scale.

Re:The dark matter between their ears

[Anonymous Coward]

gravity is as instantaneous as people can detect - ie its not at the speed of light. This makes C a constant, not a limit.
Quite like measuring the speed of propagation of force or effect when you pull on one end of a 3km rope, for example. How long would it take for the propagation?

on a different scale, if you use heavy machinery to move water on one side of a pool, the effects will be detectable on the other side at a time determined by density, elasticity and other factors however if you take that same pool and crystallize it (think freezing for example) and do the same - the effects don't take so long.

This concept may not make sense at first but if you ponder over it while checking any preconceptions at the door, you might just start to see what they're missing.
If you ponder a little while more than that, you just might realize why light can actually block (shatter?) gravitational effects, as shown in very simple, easily reproducible experiments.

Re:The dark matter between their ears

[Maritz]

What's your definition of large? I said it could be hidden matter that interacts gravitationally, or gravitational theories need to be modified. It appears that you've hung your hat on MOND. Personally, I'm just curious to see what the answer will turn out to be. Neither outcome will upset me.

Re:The dark matter between their ears

[khallow]

gravity is as instantaneous as people can detect - ie its not at the speed of light.

That is not actually known. We still haven't figured out if gravity propagates at the speed of light or not.

Re: The dark matter between their ears

[Anonymous Coward]

'Dark Matter' is the *label* for the cause of those gravitational perturbations. It is called such, because it *behaves* like matter, but is 'dark' in the sense that it doesn't seem to emit any radiation that we can detect (so far).

If it turns out to be 'space-leprechauns', then 'dark matter' and 'space-leprechauns' are simply two names for the same thing.

Re:The dark matter between their ears

[Anonymous Coward]

Medieval astronomers did NOT add "epicycles on epicycles." ...
it wouldn't have been basically impossible (in a practical computational sense) for medieval astronomers to add "epicycles on epicycles,"

Copernicus did NOT eliminate epicycles. In fact, as he tried to make his system more accurate, he actually ended up introducing MORE epicycles than the standard Ptolemaic model.

Which is it? Did Copernicus add "more epicycles", or was it "basically impossible...to add" epicycles.

Re:The dark matter between their ears

[cyberchondriac]

Question: From TFA:

"Dark matter may make up 27% of the Universe's energy density, compared to just 5% of normal (atomic) matter, but in our Solar System, it's notoriously sparse. In particular, there's just a nanogram's worth per cubic kilometer."

So then, if it's 27% vs 5%, normal matter occupies roughly only about 0.185 of a nanogram per cubic kilometer? That seems on the low side.

Re:The dark matter between their ears

[Anonymous Coward]

Who is this "they"? Dark matter is actually taken as too factual for what we really know about what it may or may not be. Name me a single physicist that ignores dark matter.

Re:The dark matter between their ears

[Megol]

First it talks about dark matter in the universe in general and then (after pointing out that "... in our Solar System, it's notoriously sparse") gives the low density value.

So you can't apply the percentages that apply to the universe in general to the solar system.

Re:The dark matter between their ears

[MightyMartian]

But no one says it doesn't exist locally. Quite the opposite, everyone thinks it does. It's just fucking hard to see.

It's not that cosmologists aren't willing to look at GR, and certainly are, but no potential quantum theory of gravity suggests an alternative to dark matter. And considering we all know there is physics beyond the Standard Model, and the potential for currently only hypothetical or even unpredicted particles, the idea that we should just toss out one of the most successful scientific theories in history because we're confronted with what looks like a lot of extra mass seems absurd.

But I get it. There is a certain type of person, underachievers mainly, whose only contribution to any discussion is to find the gaps in our knowledge and then proclaim researchers in those fields retards. It's pathetic, and contributes absolutely nothing.

Re:The dark matter between their ears

[SuperRenaissanceMan]

You know, if somebody registered that, they could make a slash without a beta.

Re: The dark matter between their ears

[Anonymous Coward]

The part you're missing is that space leprechauns also go by the name of Dark Matter. So really you're making a distinction without a difference.

Re:The dark matter between their ears

[ZeroPly]

Isn't it equally likely that the gravitational constant is not actually a constant, but varies across different regions of the universe? Dark matter is just a way of forcing equations to match reality, without acknowledging the equation might be wrong. It is the modern equivalent of aether.

Re:The dark matter between their ears

[dissy]

I don't have to provide alternative explanation to point out that what I see here is an ungrounded assertion. They're trying to manipulate facts to match the theory, not the other way around like actual scientists do.

No actually you DO have to provide an explanation.
We observe things happening. We are trying to make an explanation why they are happening.

Your claim that "they are not happening" when all observations and evidence and facts show 100% of the time over a few trillions of observations that your claim is WRONG.

It's completely on your head to show why your already-proven-incorrect "thought" is not wrong.

The facts you claim are being manipulated are right there in front of your face with no manipulation by anyone - except yourself of course, who keeps insisting the facts must be ignored because they don't fit your personal crazy "theory"

So get to explaining

Re:The dark matter between their ears

[DrJimbo]

gravity is as instantaneous as people can detect - ie its not at the speed of light.

That is not actually known. We still haven't figured out if gravity propagates at the speed of light or not.

In 1916 Einstein figured out that gravity propagates at the speed of light. We just haven't measured it directly yet.

Re:The dark matter between their ears

[Anonymous Coward]

quite amazing that some here are responding to a non-existant comment about gravity - maybe it was deleted?
if so, why?

It really makes it look like the slashmods have an agenda when they delete comments that are relevant and on topic.

At any rate, gravity has been shown to "arrive" (if you want to use that term) before the light from the sun.
The implication is that it may be instant, but at the very least it is not bound the the speed of light.

Detect the light, detect the gravity: there is an 8 minute lag in apparent position of the sun vs where the gravity points to where the sun actually is.

Incidentally, this also explains the lack of gravitational waves since there is a time variation component missing when things are instant. However if the object was rapidly moving past you at a very close distance, you would see something akin to a single-crested g-wave. Also, if you monitored a particular space for changes in gravity, you would see differences over time, large differences perhaps and if you graph these, you would see some waveform no doubt, You still wouldn't find gravity being transmitted in waves though.

As the summary points out though, the massive bodies have a "wake" of dark matter where the density is enhanced by a billion times or more. is it possible that this density increase is somehow responsible for gravitational effects? Im not proposing an answer but it begs the question.

Re:The dark matter between their ears

[SharpFang]

The way it varies though - mapping out the "dark matter" - suggests interactions with common matter both ways. So it's not like "the underlying fabric varies" - it really behaves like matter, forming clouds, strands, that "hair" - it's not a generic field or a generalized property of space "resulting in galaxies".

MOND suggests some unknown as of yet function mu(a/a0). If that function was to fit the observational data, it would be incredibly complex; nothing as elegant and common as common [something]/r^2 or sqrt(v^2/c^2). It would be more like a function to describe shapes of clouds basing on air flow, temperature and humidity.

We don't know any other physical entity that would behave that way - move, flow, gather - than matter. And while still some predictions are defied and we can't say for sure it's matter, if we compare the effects to known behaviors of various physical entities - waves, fields, energies - this one has strong similarities to matter and very few to others.

For example, space expansion is uniform; about all of cosmos expands at the same, flat rate that slowly changes over time, but is independent of location. Its source is described as "dark energy" but you can have justified doubts if it's really energy because its interaction with reality seems really unidirectional: it affects space, but the space and its contents don't seem to affect it. In case of dark matter though, the similarities are striking.

And if you think about difficulties of detecting it - it doesn't interact with electromagnetism... What percentage of our observation methods are not based on electromagnetism? All known matter keeps its structure - solid, gas, structure of atoms - due to electromagnetic forces. Bindings between atoms are all about electrons and protons interacting electromagnetically. All of light is EM wave. Most of non-electromagnetic observations like neutrina or collisions of neutrons - boil down to interactions that *eventually* produce some EM influence; be it an emitted photon, a neutron decaying into a proton and an electron, and so on - we observe them indirectly. If Dark Matter doesn't interact electromagnetically, it could sit right in front of our noses and we'd be unable to spot it. A solid chunk of dark matter could directly phase through a solid chunk of steel, because there's a lot of room between electrons and the nuclei and no force (electromagnetic!) that would prevent particles of the dark matter occupying locations in between; it could even phase through the nuclei because who says it needs to follow Pauli's Exclusion Principle? It's enough that it interacts gravitationally, and so your chunk of steel would exhibit 30% higher gravitational pull - but since its original gravitational pull is piconewtons, the change would be undetectable.

Re:The dark matter between their ears

[Anonymous Coward]

experiment trumps math - this is no exception despite Onestone's mathgic

Re:The dark matter between their ears

[G00F]

I kind of of thought of dark matter as, the matter of light that we cant measure at rest, but there is so much out there it adds up.

Stars send it out, but when it strikes celestial bodies such as earth it collects. But most of it it falls out as earth moves along it's orbit as it's low interactive to all things including gravity.

Re:The dark matter between their ears

[Anonymous Coward]

Please give me any kind of evidence that the magical "dark matter" (chuckle) exists anywhere outside of sci-fi books and movies. When you do, I will start thinking about an alternative theory. I'm not holding my breath though.

Re:The dark matter between their ears

[Bengie]

Dark Matter's effects have been measured with 9 sigmas of confidence, well beyond the requirement to show something is there. And we know of sure that "something" cannot be barionic. We have better measurements of Dark Matter than Relativity.

Re:The dark matter between their ears

[KGIII]

It's just a glitch in the program. It's a holographic universe, after all. Really, it's a holographic multiverse. We're just one of many!

Obviously, I'm not serious.

Or am I?

Re: The dark matter between their ears

[Anonymous Coward]

Gravity does not propagate. It is a field. Gravitational waves propagate at the speed of light, for the same geometrical reason that light goes at that speed. IAAP

Re:The dark matter between their ears

[Bengie]

One of the smartest minds on the subject, as determined by the community of highly regarded physicists, of MOND did almost 10 years of math and came up for an answer for MOND. But it required an unknown non-baryonic matter. He reinvented Dark Matter. It also required that we ditch Relativity. As it stands, it seems that even MOND requires Dark Matter. It also seems that Relativity is now dependent on Dark Matter. Any theory that tries to get rid of Dark Matter also needs to reinvent Relativity. Good luck with that.

Re:The dark matter between their ears

[KGIII]

Do you actually understand what you're speaking about? Dark matter is not, absolutely, any one thing. Dark matter is a reference to something we're unable to view and can only speculate about. Dark matter exists, by default, because we can not see it and we can demonstrate and measure that we're not seeing something. What that something is, is open to speculation. However, dark matter absolutely does exist. We can't see it - that's WHY we call it dark matter. It's there. We can measure and tell it is there. We speculate as to what it is but only a few overeager journalists are making statements about this being definitive. Everyone else knows that it is speculation - except for you.

Do you even science? I'm not even a scientist (my degree is in mathematics) and even *I* know this. Well, I guess, for some definitions, I am a scientist but I don't think of myself as one. I've done very few lawful or not-sexually-related things while wearing a lab coat, for example. I'm certainly not an astrophysicist. But even *I* understand this. No, dark matter does - by very nature of what it means - exist. We know it exists. We have some working models that try to explain it but they're not completely working yet so I guess we could call them half-working models. These speculations are based on those models and we'll use those models until someone proposes something better to explain the unaccounted gravitational effects that we can not see but can measure the effects of.

Again, we call it DARK MATTER because it exists and we can measure it but we can not see it. Because we can not see it, it's called DARK MATTER. (I'm pretty sure of this, at any rate - the disclaimer about my not being an astrophysicist is completely and obviously true.)

I mean, yeah, there are competing models that include things like this all being a 2D model and we're living in a hologram and thus are holograms ourselves but we don't really take those guys very seriously because they're more akin to God-botherers than they are akin to scientists. If you've got a compelling theory to explain this and maybe some maths to back it up, I'm sure they'll be happy to read your paper. Given that you don't actually seem to know what dark matter is and why we call it that and how we know it's there then I'm not actually sure how well your paper will make it through the peer-review cycle.

Is it a full moon or something? :/ Meh... Maybe it is me who's missing something. That could be true but I'm pretty sure that Brian Cox explained this nicely. I think even Morgan Freeman's gabbed about it but he's just reading a script. The little Asian guy from the college in has spoken about it too.

Re: The dark matter between their ears

[Bengie]

We can't see atoms are there either. Your point?

Re:The dark matter between their ears

[KGIII]

This logical fallacy is repeated so frequently that I think it needs its own name. I think "appello propter indispositionem" (appeal to ineptness) or "appellare multiplicitate" (appeal to complexity) are both appropriate. It's too complicated, we can't possibly be right! It's too hard, there's no way that's possible!

Re:The dark matter between their ears

[Bengie]

Too factual? They have its effects measured to 9 sigmas. We may as well be arguing whether the gravity exists. We "know" it's there, we just don't know how.

I used "stop ignoring me" to grab attention and add some humor. It's not so much that it was being ignored, but that it was being questioned. 100 years of observations and geniuses, and not a single iota against it and a mountain of everything for it.

Re:The dark matter between their ears

[Anonymous Coward]

Have you ever heard of neutrinos? There are 1e11 of them going through every square cm of you every second, and the chance of one of them interacting with your atoms is once in 30 years. If fact, they could have been a candidate for dark matter, but we now know there just aren't enough of them to make up the total dark mass.

So if there already exists a particle that is almost dark (i.e. almost not interacting via electromagnetic, weak, strong force), why is is so hard to believe there could be particles that are even darker?

Re:The dark matter between their ears

[Anonymous Coward]

Please stop calling deductions "facts." Nobody has the means to directly measure the gravitational force between galaxies. These values are calculated using assumptions based upon models. When these calculations have been done the model breaks unless something is imagined to reconstitute the possibility of the model's validity. The solution has been to imagine something with mass but without other interactions. At this point in time such a substance is entirely imaginary. It may be that the model is fundamentally flawed and no such matter exists. Your argument pretty much requires the mischaracterization of conclusions drawn from models as fact in order to defend the model. In other words it is a predetermined outcome as the model is assumed from the start. It is taking the notion that the model is fundamentally flawed off the table prior to presenting a train of thought to defend the model. Calculated values based upon a model can not properly be considered fact in order to defend that same model. What IS fact is that the current model is non-viable unless there is something we can't see and have not seen. There are many instances of measurement in our physical world. The explanation of why we do not detect dark matter in ANY other set of measurements obtained outside of cosmologist's imaginings is the convenient "It must be that dark matter is rare in our solar system." This is a blatantly obvious manufactured convenience as no one has actually detected any dark matter in the first place. Concluding that the existence of dark matter is unsupported is entirely reasonable at this point in time. I agree that the assumption of dark matter helps make calculations consistent. Even when it was apparent and agreed that the old Greek model was obviously incorrect due to the direct observation of planetary phases, the best way to predict the positions of planets in the sky was by the use of epicycles. Celestial mechanics took time to develop. So we had a model we knew was incorrect yet for the purpose of calculating and predicting the incorrect model was superior. The "but it makes our math work" argument is unconvincing. This is why people bring up epicycles when dark matter is discussed. BTW nobody ever strung a bunch of names together with hyphens and called raisins and dough a reasonable or informative model. It was plums actually. It lasted about 5 years until Rutherford proved IN A LAB that sub-atomic structures were quite small. There was no amount of time where sub-atomic particle size was considered an imagined convenience. The Rutherford model was proven by experiment. The Rutherford model was the result of experimental observation not verification of some prior convenient assumption.

Re:The dark matter between their ears

[Maritz]

Dark matter is just one of two reasonable hypotheses. At the moment, it's safe to say that it's probably the more likely of the two. Modified gravity struggles to explain the bullet cluster, for example, whereas cold dark matter provides a compelling explanation. This is ultimately a scientific question that will be settled by evidence and logic.

Re:The dark matter between their ears

[Bengie]

Once you measure gravity by the gravitational lensing, galactic rotations perfectly matches Einstein. We just can't limit ourselves to matter that interacts with light. It's not hidden in the sense that we can't detect it, only that we can't see it. But that logic applies to a lot of science.

Re:The dark matter between their ears

[ZeroPly]

I am not a physicist, but why does it have to be mysterious "dark" matter that's causing the discrepancy in the bullet cluster? If it's non-luminous regular matter, we wouldn't be able to detect it either. For that matter, there might be entire classes of elementary particles that exist in those regions of space that don't exist in ours. Homogeneity of the universe is taken as canon by physicists. But this is the same logic as saying "Mercury is a planet like all other planets, and its orbit is being affected by something unknown, therefore Vulcan must exist".

Re:The dark matter between their ears

[Maritz]

I am not a physicist, but why does it have to be mysterious "dark" matter that's causing the discrepancy in the bullet cluster?

Show me where I said it has to be, and we'll go from there.

Re:The dark matter between their ears

[Maritz]

I believe we're in agreement. Lensing gives you a window into all the gravitating material and not just the baryonic matter.

Re:The dark matter between their ears

[Anonymous Coward]

For the record, theories are not tested. Hypotheses are tested and theories are derived from them. If a tested hypothesis does not yield expected results, then the hypothesis needs to re-evaluated. When the hypotheses yield expected results, then a theory is derived from them.

Re:The dark matter between their ears

[strikethree]

Correct. The facts don't match the theory. Galaxies could not hang together the way they do if all they consist of is the things we've already observed in the laboratory unless we change the law of gravity [to something enormously more complex - c.f. epicycles] or postulate the existence of something that interacts gravitationally but doesn't interact with light.

Spacetime is a continuum. Yes? Speed changes the perspective of time. Mass changes the perspective of space. No modification of gravity needed and no dark matter needed.

Put simply, there is less space where there is less matter. If you can wrap your brain around time dilation, wrapping your brain around space dilation should be simple.

Re:The dark matter between their ears

[strikethree]

Why is it that astrophysicists "believe" in time dilation but do not "believe" in space dilation? Time and space is a continuum. They are inseparable as concepts. Energy is composed of spacetime and mass. When creating mass out of energy, spacetime is also created. The amount of mass determines how much spacetime there is; and therefore how much energy was used to create it.

"Length" is not a hardcoded value just as time is not a hardcoded value. There is less "space" at the edge of a galaxy. A flat galaxy that is rotating only appears to be flat due to the interplay of time and space. It is not actually so... from the perspective that we live in.

Re:The dark matter between their ears

[ZeroPly]

You said "Dark matter is just one of two reasonable hypotheses"

I pointed out that non-luminous regular matter is also a valid hypothesis, so you are incorrect that there are only two reasonable hypotheses.

My point being - you are creating a false dichotomy. You are picking two possibilities, and saying dark matter is the more likely of those particular two. That is faulty logic.

Re:The dark matter between their ears

[Lotharus]

Your answer turned out to be incorrect? Just change the question!

Can't tell if this is part of the sarcasm implied in the first sentence. Changing the question when the answer doesn't work pretty much is what science is.

Re: The dark matter between their ears

[salnikov]

Practically all visible light that we see is emitted by atoms. So the only thing that we really see is atoms (emitting EM radiation).

Re:The dark matter between their ears

[beastofburdon]

Magnetic force does not fall off at an inverse square like gravity does, and is far more powerful. Maybe they should be looking into that first instead of making up invisible matter and energy. Then if that doesn't work then look elsewhere, but we are dealing with a religious belief here, not real science. It may involve a lot of science, but there is still a theory that they refuse to give up on even though it has been disproven over and over again.

Re:The dark matter between their ears

[beastofburdon]

There is only one question in science, though it has many variations.

Why?

Re:The dark matter between their ears

[beastofburdon]

Or there are other forces to take into account.

Re:The dark matter between their ears

[Maritz]

Maybe you straight up don't have a clue what you're talking about. Personally I consider that much more likely. It's pretty weird for you to be quite so passionate about the non-existence of dark matter.

Re:The dark matter between their ears

[beastofburdon]

To me, it's pretty weird for you to be quite so passionate about the existence of dark matter.
I am simply saying that you should look at other possibilities instead of discount them without any investigation. Sadly this has been standard practice in science as far back as we have records of scientific pursuits. When people base their world-view on a theory they fight to protect that theory with religious fervor. It is just human nature. Since I know about this nature I try very hard to fight it within myself, so when I look into things like this I also look at what opposing groups are saying. This lead me to look into the electric universe theory people. While there are certainly a few in that group that are idiots and have no idea what they are talking about, the others do know what they are talking about. If you know much about electricity and magnetism, which I do, a great deal of what they talk about makes perfect sense. Also, they are not just some group of nut-jobs who preach one thing and keep repeating it over and over again for decades. They are actually doing research and refining their theories.

PPK

[Anonymous Coward]

I read that as " a nanogram's worth per pubic kilometer"

0_o

Re:PPK

[alex67500]

I read that as " a nanogram's worth per pubic kilometer"

0_o

that, coupled with the hair thing... wow, the human mind hey?

Re: PPK

[drewsup]

Ya, dark matter grows hair around Uranus kinda grabs a headline...

Re:PPK

[Anonymous Coward]

Hairy.

Re: PPK

[reboot246]

I wondered how long it would take somebody to say that. Nobody like a hairy anus.

Increase sensitivity!

[wonkey_monkey]

if we were to position our detectors in the wake of one of these hairs – if dark matter behaves as we expect it to — the sensitivity of our dark matter detectors will improve by a factor of one billion, immediately.

No it wouldn't. The sensitivity of the detectors doesn't change at all.

When you walk into a bright room, it's not bright because your eyes have just magically got more sensitive to light.

Re:Increase sensitivity!

[Anonymous Coward]

In fact the way our eyes work, our sensors become less sensitive in a bright room due to a chemical process.
This is the reason you see a reverse after image if you look at a bright image and look away.

Re:Increase sensitivity!

[Anonymous Coward]

Bad wording.

Sensitivity wouldn't change, but (relative) accuracy of measurements would.

Say, your instrument can measure values of Blorb in range 0 to billion with accuracy of 1 blorb. If you're getting readouts with rare maximum of 2 blorbs per flargh, and more frequent results of 1 blorb per flargh, you may *guess* its levels are *maybe* Gaussian distribution.

Now if your maximum is five million blorbs per flargh, examining the distribution is vastly easier. Neither sensitivity nor absolute accuracy of the measurements changed, but the relative accuracy is finally sufficient for useful results.

Slashdot is not your personal blog

[thegarbz]

Please startswithabang, go away.

Re:Slashdot is not your personal blog

[gargleblast]

Please startswithabang, go away.

And take away that wake of credulous Forbes links where the density is enhanced by a billion times or more.

Re:Slashdot is not your personal blog

[Anonymous Coward]

...but it sure as hell beats the medium.com rampage we had a few months back. ...Others would say that a trend is emerging.

Re:Slashdot is not your personal blog

[TrekkieGod]

What the hell? Why? Seems like the articles he posts are interesting and on topic for a nerdy site.

Maybe you should go away.

Re:Slashdot is not your personal blog

[sribe]

Please startswithabang, go away.

Or at least learn the minimum necessary to post reasonably accurate summaries. I don't even have to go to the linked article to know that the research did not "demonstrate" what he claimed. What the research did was theorize about what happens when planets pass through dark matter, and demonstrate that such an effect is consistent with, in other words predicted by, current theories.

Demonstrating that dark matter is concentrated that way by a passing planet would mean detecting the dark mark and measuring the concentrations. If that had happened, I'd be reading about it in more places than here.

Re:Slashdot is not your personal blog

[dotancohen]

Please startswithabang, go away.

Right, please bring back Bennett Haselton instead! Please!

WTF?!? Is the OP serious? startswithabang seems to be one of the best serial-posters here.

Re:Slashdot is not your personal blog

[Maritz]

Someone force you to read it? Someone force you to comment? Yeah? Sucks to be you.

Re:Slashdot is not your personal blog

[Anonymous Coward]

There is a thought among many that contributors should also post a comment or two from time to time.

Re:Slashdot is not your personal blog

[gstoddart]

The second link has his username embedded in it ... which essentially means he's publishing links to articles he's put elsewhere.

So, yeah, one can see how it's a little self-promoting.

Re:Slashdot is not your personal blog

[avandesande]

I've seen them come an go over the years but this is probably one of the least benign cases of self promotion.

Re:Slashdot is not your personal blog

[thegarbz]

Because this site is a news aggregation. If we wanted to read every thing he posted then maybe it would make sense to, oh I don't know, subscribe to his site?

His stuff is mildly interesting, but I'm sick of the 2-3 people who treat Slashdot as their personal blog. It used to be that people avoided getting linked to Slashdot for fear that it takes out your server. Nowadays you do your best to link every shitty click-bait article to Slashdot for the ad revenue. Everyone. As in we see his shit multiple times a week.

Re:Slashdot is not your personal blog

[thegarbz]

WTF?!? Is the OP serious? startswithabang seems to be one of the best serial-posters here.

Yes the OP is serious. Seriously disappointed that someone thinks there's anything "best" about serial-posters.
I guess Slashdot has turned into a personal blog for a few.
The occasional article is not an issue. The flat out serial posting of every one of his articles while at the same time having zero contribution to the site means he's using the site as a personal cash grab with Dice's support.

But hey I guess that's what Slashdot has turned into these days. Page hits for nerds, adclicks that matter.

Re:Slashdot is not your personal blog

[Anonymous Coward]

Seems like the articles he posts are interesting and on topic for a nerdy site.

Yes, it seems like it from the summary, but the actual articles are lots of pretty pictures and a bunch of rambling empty words. And they get put up here just about every day, no matter how bad they are.

Re:Slashdot is not your personal blog

[Coren22]

this is probably one of the least benign cases of self promotion.

http://dictionary.reference.co...

So lets reverse what you just said. This is the most harmful case of self promotion. Is that what you meant to put there?

Re:Slashdot is not your personal blog

[Coren22]

Yes, there is a guy here with a gun to my head, please send help! (or don't, because that was a terrible attempt at sarcasm...)

Re:Slashdot is not your personal blog

[gstoddart]

I don't entirely disagree ... but a lot of people prefer not to see something submitted which boils down to "hey, look what I have over here", especially if that submitter might actually benefit from the self promotion. And most especially if they don't give us the courtesy of adding the disclaimer which says "I'm on the payroll and this is mine".

So, like when Nerval's Lobster gets something accepted which inevitably links back to dice.com, we pretty much know he's a paid shill who gets preferentially published. But we only know it because we've seen it, not because anybody has made any great effort to point it out.

We just want to KNOW when it's self promotion, instead of having that fact be very opaque. And bumping up your hits on Forbes by submitting a link to your article on Slashdot ... well, it's still self promotion. Especially if those extra hits on Forbes impact your compensation or retention by Forbes.

It might be relatively benign, but fess up to it in the summary instead of just pretending you stumbled on something awesome. Otherwise people assume it's not so benign.

Re:Slashdot is not your personal blog

[Anonymous Coward]

And Gee whiz, isn't Science wacky, exclamation point!!!1one!

I'm the biggest pencil-neck geek in town but I have an irresistable urge to give this Ethan dweeb a wedgie.

Re:Slashdot is not your personal blog

[RockDoctor]

The guy has got up my nose more than a few times with that shit that he used to do through - was it Medium, Vice, or MediumVice, or some such piece of shit. It got to the point that I was looking for ways to actively block his stuff from coming up again (short of completely trashing Slashdot.

But props to the guy - he has improved his posting somewhat the last couple of months, and has squeaked back into being worth paying attention to. In particular, in this one he STARTS with a link to TFP (that The FUCKING PAPER, for the multitude of Slashdotters whose association with science is more in their imagination than the reality) on ARXIV. So I think he's learning his craft.

I've no idea what his writing on Forbes is like because I can RTFP, so I don't need second hand presentations. But if he's trying to be a science journalist there, then the fact he's appreciating the importance of primary sources is worth noting and encouraging.

String theory?

[MPAB]

Does this have something to do with string theory?

Re:String theory?

[Anonymous Coward]

I have some dark matter and hair growth around my bottom star. Strings don't work for me. So no.

Re:String theory?

[Anonymous Coward]

No.

Re:String theory?

[grimJester]

Well, weakly interacting massive particles are a candidate for dark matter, some supersymmetric theories naturally include such particles and string theory requires supersymmetry.

Not much of a link, but afaik about as much of a link as it's possible to get between string theory and experiment.

Re: String theory?

[Anonymous Coward]

Whoosh

Re:String theory?

[Maritz]

Some string theories predict particles at different energy levels with different masses (supersymmetry), and some of those particles would be cold dark matter candidates, like a neutralino.

Re:String theory?

[myowntrueself]

I have some dark matter and hair growth around my bottom star. Strings don't work for me. So no.

Try swallowing a string tied to a strip of muslin cloth. That should eventually help with the dark matter thing.

That explains the hair in my ears

[Anonymous Coward]

I must have a few nanograms of dark matter in my ears.

Re:Great.

[3.5 stripes]

Possibly, but it's going to be invisible to any of the light spectrum we work in, though I do wonder if would be something neat to have the ladies caress your invisible locks of dark matter hair (sounds better than hairy dark matter)..

Re:Great.

[Anonymous Coward]

Yes, please see my sales pitch below.

Dark Matter = Closet Aether Theory

[Anonymous Coward]

So, perhaps we can finally admit that an Aether field does exist, even if it isn't as simplistic as the traditional concept, instead of "hiding in the closest" about it with things like virtual particles, dark matter and dark energy? That the presence of large quantities of mass (planets) cause large pressurized displacements of said field? That local gravitational force is the result of this local pressure field, and not due to a perpetual attraction? That the orbits of the planets around the Sun are not due to two orthogonal perpetual forces at play, nor due to an effective mathematical detour of calling space and time curved, but is due to a balance of such "dark matter" at the system level -- a direct result of body densities in a real field?

No? Didn't think so. Diving into real mechanical explanations just isn't as profitable or exciting as producing crank Quantum Heuristic theories that make the front page of science mags and ensure job security for mathematical magicians :)

Re:Dark Matter = Closet Aether Theory

[Anonymous Coward]

Thing is, Aether was meant to be an "anchor" - a selected reference frame for movement of light. Meaning it to be directly, firmly bound to EM radiation, an essential concept related to electromagnetic waves.

Dark Matter is completely oblivious to Electromagnetic spectrum, specifically entirely ignores it.

It might be some kind of aether, some field that is a source of gravity, that is fixed in space and has its own specific frame of reference. But it's definitely not what was discussed as the Aether in times when Einstein disproved it. Different interactions, different properties, an entirely different cup of tea - bound to gravity but entirely decoupled from EM, which original Aether was all about.

Re:Dark Matter = Closet Aether Theory

[Anonymous Coward]

Thing is, Aether was meant to be an "anchor" - a selected reference frame for movement of light. Meaning it to be directly, firmly bound to EM radiation, an essential concept related to electromagnetic waves.

Sort of correct. However, you are interpreting things from the SR/GR viewpoint, which makes your statement somewhat revisionist. Aether theories were diverse and plentiful, but you are perhaps focusing on the one that Maxwell would have implied.

Dark Matter is completely oblivious to Electromagnetic spectrum, specifically entirely ignores it.

How does that quote go: reality is that which continues to be, even when you stop believing it? You can ignore reality, but reality will not ignore you :)

It might be some kind of aether, some field that is a source of gravity, that is fixed in space and has its own specific frame of reference. But it's definitely not what was discussed as the Aether in times when Einstein disproved it.

Einstein never "disproved" any interpretation of Aether. In fact, he was quite happy to map the concept to his findings... though statements made by him regarding "Aether" tend to be ignored by those who subscribe to QM. You should remember that Einstein was never happy with the non-physical meddling from the likes of Bohr or Heisenberg: "God does not play dice!" He knew instinctively that their theories being un-grounded from reality meant they were heuristic only, that they can only be used to model effects and not describe the underlying causes. This caused a shift in the scientific mindset that we must pursue the math at any cost to theory, i.e. the Feynman (mathematical purist) school of thought.

However, you do make a good point. If we continue to think of this field as some sort of fixed frame of reference, an absolute "grid" that we can graph ourselves against, we will continue to make zero progress. Such a field is probably a lot more fluid and less "fixed" than historically thought, and that the MM experiment should by definition be a null result.

If the MM experiment found light moving relative to another field, that would be the actual evidence needed to pursue the current theories. However, the MM experiment proved that light is also being dragged, producing the null result. This has been interpreted perfectly backwards, leading to the current mindset.

You see, since Earth is moving through space at high speeds, and if there was no drag, a laser beam (the photons, actually) should effectively miss whatever they were aimed at. The longer the distance, the larger the miss. Since even laser light tends not to miss targets at all, even at distances as large as to the Moon and back, the photons must be experiencing momentum. This momentum can be interpreted as a drag by an underlying field, or it can also be used to prove that photons do have rest mass, albeit minuscule and currently beyond our detection... and perhaps permanently beyond our detection since the mainstream interpretations have already drawn the conclusion that they must be mass-less particles that exhibit energy-mass, only.

So now you have two logical conclusions from the MM experiment: there is an Aether field of sorts, or photons do have rest mass. However, the null result cannot support the current theories in any way, shape or form as they directly contradict the premises of those theories. Also, this does not imply that the aforementioned two conclusions are the only two available, only that the current standard conclusions are logically flawed and must be incorrect. Although, based on the history of QM, reinterpreting the logical conclusions of MM to retroactively fit their theories is only an ad-hoc hybridization wave of a mathematical-wand away. See! Isn't it glorious when you decouple yourself from the ickiness of reality :)

Different interactions, different properties, an entirely different cup of tea -

Re:Dark Matter = Closet Aether Theory

[Anonymous Coward]

I'm pretty sure you already posted further up, AC. Face it; you're the crank. No amount of sarky-toned posts is going to stop you from being the crank.

Yes, that was me. That should have been fairly obvious, despite posting as AC in order to avoid being trolled by closed-minded zealots.

Also, nice ad-hominem. It proves you have nothing useful to add to the discussion.

Whenever you have come to the conclusion that you must be right and that others must be wrong, you have stepped into the realm of religion, not science.

In science, the only tools we have are logic, provability and falsification. In science proper, we don't find comfort in morality or simply go with the popular opinion... we follow the leads in a logical manner, and make sure to constantly keep our conclusions/assumptions in check. QM has skirted the fundamentals of science for nearly a century now, yet I am the crank? Check your biases.

Re:Dark Matter = Closet Aether Theory

[Anonymous Coward]

I'm pretty sure you already posted further up, AC. Face it; you're the crank. No amount of sarky-toned posts is going to stop you from being the crank.

Yes, that was me.

Let me clarify. I am the proponent of "Dark Matter = Closet Aether Theory" but I am not the AC of "The dark matter between their ears" if that is what you were implying; although, that AC indirectly makes my point for me :)

Re:Dark Matter = Closet Aether Theory

[Anonymous Coward]

"Dark Matter is completely oblivious to Electromagnetic spectrum"

Last I heard this is at least partially incorrect, there are astrophysicists who claim they are able to map Dark Matter regions using gravitational lensing around dark matter.

Re:Dark Matter = Closet Aether Theory

[SharpFang]

"which "original" Aether theory are you formally referencing?"

The one Michelsonâ"Morley experiment failed to detect.

Re:Dark Matter = Closet Aether Theory

[Anonymous Coward]

Yes, that's the *gravity*, not the dark matter itself.

Re:Dark Matter = Closet Aether Theory

[Anonymous Coward]

"which "original" Aether theory are you formally referencing?"

The one Michelson-Morley experiment failed to detect.

OK. Let's make things even more simple than the Michelson-Morley (MM) experiment. Say you are standing on the face of the Earth, looking forward. In front of you is a laser that is aimed directly away from you -- aiming in the direction you are looking. Both you and the laser are focused on a flat reflective target directly in front of you, but quite some distance away; say, 300 meters.

The laser is attached to a theodolite that allows you to aim it at the dead-center of the bulls-eye of an archery-like target -- the one that is 300 meters away in this case. The laser and theodolite were designed and calibrated to physically ensure that the laser shoots perfectly forward as per mechanical alignment. In other words, the laser should always hit whatever is indicated by the center of the theodolite alignment.

Now, let's add a realistic fact: the Earth is not stationary. The Earth, and the entire solar system, is moving at approximately 230 km/s through space, or approximately 1300 times slower than the speed of light. You, the laser and the target are aligned orthogonal to the direction of movement for the duration of this experiment, i.e. you are all moving 230 km/s sideways through space.

We are going to eliminate the atmosphere, and say that you are standing in a vacuum. In this scenario, the speed of light is approximately 300,000 km/s. For a target 300 meters away, it should take the laser light about 0.000001 seconds to hit the target; and in that same amount of time, you, the laser and the target will have moved sideways 23 centimeters.

Now, what do you expect to happen when you fire that laser dead center at the target? Should you honestly hit the center if light is composed of mass-less energy particles that cannot experience a sideways momentum? No, you should be 23 centimeters off target. Even by adding an atmosphere and other corrections back in, you should not hit the center of that target.

In reality, you'll find that you can repeatedly hit the center of the target with high precision, even at distances as far as the Moon. This is what I was talking about when I said the MM experiment should provide a (virtually) null result if an Aether theory is true: BECAUSE YOU ARE INSIDE THE FIELD. Observer effect, at its best. However, this doesn't necessarily mean an Aether theory is the only possible explanation. Photons having rest mass, i.e. being a real and physical but minuscule particle, was another possibility. Another amusing possibility is that a dense field of photons is the Aether, which happens to show up as the CBMR, dark matter and dark energy, depending on how you are measuring things.

However, this all does necessarily mean that the mainstream interpretation of the MM experiment is fantastically wrong... it is perfectly backwards!

Re:Dark Matter = Closet Aether Theory

[Bengie]

Ironcailly, it's been shown(for the most part, but not truly proven) that without Dark Matter, we need Aether, because MOND does not work without a reference frame.

Re:Dark Matter = Closet Aether Theory

[Bengie]

Minor correction: "without a universal reference frame"

The hair around Earth is *nothing*

[Anonymous Coward]

You should see the dark matter in the hair around Uranus!

Re:The hair around Earth is *nothing*

[Anonymous Coward]

You should see the dark matter in the hair around Uranus!

Those would be...

Klingons!

rimshot

Thank you. I'm here until Tuesday. Tip you server!

Let Me get this correct here

[Anonymous Coward]

Dark Matter grows hair around uranus?

Sun's hair

[Anonymous Coward]

How big and long is Sun's hair?
The arXiv paper's too technical for me. The last section seems to say that detectors in space are not that great, since we'd need to know precisely where the root of the hair might be.

Ockhams's razor

[Anonymous Coward]

Would the razor act like this:

Given two theories of gravity, one of which is consistent with observations and another that is only consistent with observations if an invisible "god"-like dark matter exists, dark matter that is detectable in no other way, then Occam's razor says that the theory without the dark matter is more likely to be true...?

Unfortunately, we don't have such a theory of gravity, so the razor can't cut.

Re:Ockhams's razor

[SharpFang]

Yes, it would - given a theory fully consistent with the observation without the "god-like" dark matter. Which we don't have.

So until either a workable alternate theory is developed, or we manage to disprove Dark Matter through other means (e.g. discovering it's not actually matter) it's there to stay.

Re: Ockhams's razor

[Anonymous Coward]

MOND is NOT a theory. It's an empirical fit (i.e. a law, which is less than a theory). IAAP

Re:Great.

[Anonymous Coward]

Only if your head is the size of a planet.

bullshit

[Anonymous Coward]

We didn't detect them (yet), but we already know they grow hair on planetary bodies???

Re:bullshit

[Maritz]

Precisely no-one said that, well done you managed to miss not just some, but all of the point. Congrats.

It stings...

[burtosis]

Prézeau’s work is particularly stinging for me, because about a decade ago, as a graduate student, I was asked by my advisor to consider this problem, which I did. But in my analysis, I only considered the effect that the passing dark matter would have on the planet’s velocity, not of the density enhancement in the planet’s wake.

Ya man i know what you mean. I almost solved a quantum formula for gravity myself as my advisor asked me to solve a similar problem. But all i did was use formulas like mg(h2-h1)=E and assumed frictionless spherical cows.

In Before...

[Anonymous Coward]

I presume there will be jokes about hair around Uranus.

Re:Great.

[Anonymous Coward]

Great comment. Really top.

Huh

[koan]

So the Universe is made up of hairy balls... that explains a lot.

Re:Huh

[Anonymous Coward]

Well, it is Movember after all!

So what is "god like" about dark matter?

[Anonymous Coward]

Does it have individuality as a homogenous lump, with active participation and will to act? Does it cause things to move other than as expalined by simple undirected forces, causing miracles?

No.

So what, other than you hate it, is "god like" about dark matter?

Oh, and if you have a better theory of gravity that explains things better, come on with it.

And, no, saying "Oh, it's just modify newtonian dynamics" isn't it. Modify it AND EXPLAIN WHY IT IS SO MODIFIED and apply that same modification to all the observations that require explaining.

You know, do actual fucking work, not just whine about those who do.

So Black Holes must have hair

[Anonymous Coward]

After all.

Re:Great.

[kilfarsnar]

Look at the size of that boy's heed.

I'm not kidding, it's like an orange on a toothpick!

Well, that's a huge noggin. That's a virtual planetoid.

Has it's own weather system!

A time machine would be really neat

[Anonymous Coward]

Then I could see how this stuff really works

At this point we have a lot to learn.

Hairs are for Cows

[Anonymous Coward]

You are all Cows. Cows say Mooo. Moooo! Mooo! Mooo cows Mooo! Moo osay the cows. YOU HAIRY DARK COWS!!!

growing up so fast...

[Jaegs]

So, in the chronology of the creation of the universe, we've officially hit the puberty epoch. Congratulations, universe! You are growing up so fast.

I guess you could say

[The-Ixian]

Those are some big hairy balls...

Re:I guess you could say

[Anonymous Coward]

Perhaps try using that Occam's razor thingy to trim those up a bit?

Re:Great.

[3.5 stripes]

Yours too, glad I read it.

No, Black Holes are bald

[Anonymous Coward]

Since the hair is essentially made of dark matter that went through the body considered. Black holes just wipe all dark matter clean.

Experiment 1

[Tablizer]

Send some politicians and Comcast executives into the wake stream for a few decades and see what happens to them. Don't waste perfectly good chimps.

multiple lines supporting evidence

[peter303]

Too rapid galaxy rotation, too rapid galaxy cluster movements, too strong gravitational lensing, cosmic microwave background spatial spectrum. Alternative theories like Modified Newtonian Dynamics may explain one or two of these, but not all of them.

Re:multiple lines supporting evidence

[Anonymous Coward]

That's just evidence proving that the current understanding of gravity is wrong then. Bringing "dark matter" and other inanities is no different than saying "G-d did it".

dark energy may be more related to aether

[peter303]

As an intrinsic property of vacuum energy. Most dark matter proposals still treat it as a special substance that varies in density around the universe.

The Sad State of Astrophysics and Cosmology

[paradigmsareconstruc]

I see that there remains an aversion here to questioning the cosmic plasma model. Rather than investigate the dark-mode filamentary plasmas we already observe crisscrossing the galaxy on numerous scales, theorists continue to play with their simulations -- and the public continues to buy into the notion that this is science. How many more decades will this go on?

Travelling deformations of space

[Anonymous Coward]

DM halos around large bound structures are caused by wrinkles in space time very loosely analogous to frame dragging. Space always wants to expand uniformly yet is complicated by gravity wells of massive objects in which a surplus of negative pressure diffuses into surrounding space. The additive effects of propagation of these distortions cause wrinkles or "ghosts" to appear as ever expanding after-images of mass.

We don't see it locally because expansion of metric is extraordinarily slow and worthless at small scales yet at larger scales it appears as a diffuse cloud. This effect is not a property of gravity it is a property of dark energy emanating from the belly of an Internet troll.

Re:Travelling deformations of space

[Bengie]

If that was the case, then wouldn't DM show up as smeary instead of clumpy?

Obligatory

[Anonymous Coward]

Has anyone scoped out Uranus for dark hair?

[Somebody had to post it.]

- T

Now I know where it comes from

[Anonymous Coward]

"Dark matter grows hair around...planets."

It finally explains that hair around Uranus.

G R A V I T A T I O N A L * * * W A V E S

[cyberspittle]

Predicted by Einstein

Coren22's impersonation "APKolypse"

[Anonymous Coward]

Coren22 IMPERSONATES RESPECTED MEMBERS OF THE SECURITY COMMUNITY http://slashdot.org/comments.p...

---

"privilege escalation's a bad thing" - by Coren22 on Tuesday September 22, 2015

How else programmatically update it?

"requires elevation to write hosts" - by Coren22 (1625475) on Wednesday September 23, 2015

Hypocrite later admits it - hosts do vs. WFP/SFP not my ware. Users set it not programmatic impersonation. Security wares need it.

---

"secretary at MalwareBytes took a look at his source code & said it looked all good" - by Coren22 (1625475) on Wednesday November 18, 2015

Mr. Steven Burn of Malwarebytes

"yes I've seen the code & yes it is safe." FROM http://forum.hosts-file.net/vi...

---

"we should avoid your crap it looks like malware." - by Coren22 (1625475) on Monday November 02, 2015 @03:52PM (#50850445)

60++ reputable sources say different:

64-bit model https://www.virustotal.com/en/...

+

32-bit model https://www.virustotal.com/en/...

&

Installer-> http://f.virscan.org/APKHostsF...

MalwareBytes' hpHosts Admin (MalwareBytes employee) hosts & recommends it -> http://hosts-file.net/?s=Downl...

---

"MiTM... his software provides" - by Coren22 (1625475) on Wednesday November 18, 2015

Hardcoded favs users provide = REVERSE DNS verified & my ware filters 5,500++ false positives - security site hosts data = false positives filtered.

---

"Apk doesn't think DNS servers are worth running & believes Microsoft Active Directory can run w/out DNS." - by Coren22 (1625475) on Tuesday October 27, 2015

Show us where I say it? Not illogic logic but where I say it. I say AD needs internal DNS far back as 2007

http://forums.tweaktown.com/wi...

See "To warn users who have ActiveDirectory/AD LAN-WAN setups to NOT use external DNS servers" there.

APK

P.S.=>

"modding you down for trolling in your signature" - by Dog-Cow (21281) on Wednesday November 25, 2015

Dog-Cow's (old acc't. no new sockpuppet from you) thoughts of your signatures about me

... apk

Coren22's impersonation "APKolypse"

[Anonymous Coward]

Coren22 IMPERSONATES RESPECTED MEMBERS OF THE SECURITY COMMUNITY http://slashdot.org/comments.p...

---

"privilege escalation's a bad thing" - by Coren22 on Tuesday September 22, 2015

How else programmatically update it?

"requires elevation to write hosts" - by Coren22 (1625475) on Wednesday September 23, 2015

Hypocrite later admits it - hosts do vs. WFP/SFP not my ware. Users set it not programmatic impersonation. Security wares need it.

---

"secretary at MalwareBytes took a look at his source code & said it looked all good" - by Coren22 (1625475) on Wednesday November 18, 2015

Mr. Steven Burn of Malwarebytes

"yes I've seen the code & yes it is safe." FROM http://forum.hosts-file.net/vi...

---

"we should avoid your crap it looks like malware." - by Coren22 (1625475) on Monday November 02, 2015 @03:52PM (#50850445)

60++ reputable sources say different:

64-bit model https://www.virustotal.com/en/...

+

32-bit model https://www.virustotal.com/en/...

&

Installer-> http://f.virscan.org/APKHostsF...

MalwareBytes' hpHosts Admin (MalwareBytes employee) hosts & recommends it -> http://hosts-file.net/?s=Downl...

---

"MiTM... his software provides" - by Coren22 (1625475) on Wednesday November 18, 2015

Hardcoded favs users provide = REVERSE DNS verified & my ware filters 5,500++ false positives - security site hosts data = false positives filtered.

---

"Apk doesn't think DNS servers are worth running & believes Microsoft Active Directory can run w/out DNS." - by Coren22 (1625475) on Tuesday October 27, 2015

Show us where I say it? Not illogic logic but where I say it. I say AD needs internal DNS far back as 2007

http://forums.tweaktown.com/wi...

See "To warn users who have ActiveDirectory/AD LAN-WAN setups to NOT use external DNS servers" there.

APK

P.S.=>

"modding you down for trolling in your signature" - by Dog-Cow (21281) on Wednesday November 25, 2015

Dog-Cow's (old acc't. no new sockpuppet from you) thoughts of your signatures about me

... apk