Researchers suggest dark matter disk in Milky Way plane could signal rash of comet strikes on Earth

May 01, 2014 by Bob Yirka report
Our Solar System orbits around the Milky Way’s center, completing a revolution every 250 million years or so. Along this path, it oscillates up and down, crossing the galactic plane about every 32 million years. If a dark matter disk were concentrated along the galactic plane, as shown here, it might tidally disrupt the motion of comets in the Oort cloud at the outer edge of our Solar System. This could explain possible periodic fluctuations in the rate of impacts on Earth. Credit: Physics 7, 41 (2014) | DOI: 10.1103/Physics.7.41

(Phys.org) —A pair of researchers at Harvard University has published a paper in the journal Physical Review Letters, in which they suggest that a dark matter disk hiding in the Milky Way plane might be responsible for causing asteroids or comets to head our way. In their paper, Lisa Randall and Matthew Reece suggest that such a dark matter disk could pull other bodies from the Oort cloud, some of which could wind up heading toward Earth.

It has been noted by scientists that asteroids and comets tend to strike the Earth in a cyclic pattern that occurs approximately every 35 million—as evidenced by telltale craters. But why such a cycle might occur is still up to conjecture. Some have suggested it's due to a mysterious planet hidden from our view, or perhaps the presence of an as yet undiscovered companion star. In this new effort, the research duo suggests it might be due to the of a disk residing in the Milky Way Galaxy plane.

This is not the first time that scientists have suggested such a disk might exist—it's been suggested that a dark matter a disk would explain why our galaxy doesn't spin apart. It is the first time, however, that such a disk has been proposed as an answer to why our planet gets bombarded periodically with asteroids or comets.

In their paper, Randall and Reece note that the conventional view of the material that makes up dark matter, wouldn't work as a means of pulling other bodes from where they currently reside, it's evident in their name—weakly interacting massive particles. They suggest that some dark matter could be made instead of what they describe as "strong electromagnetic-like interactions among " which by their nature would exert a greater gravitational pull. And if that were the case, then it would seem plausible that as our solar system circles around the center of our galaxy, most particularly as we move closer to the Oort cloud, some of those bodies that exist there, could be jostled, which in turn could cause some of them to wind up on a collision course with our planet.

This new theory by the research pair has some problems—it assumes the periodicity of crater creation has been firmly established, which it hasn't, and, scientists aren't even sure which craters on the Earth's surface were cause by what sort of object. In any event, the theory is expected to gain or lose credence as the European Space Agency's Gaia mission gets underway—it's supposed to give us a better view of the Milky Way Galaxy than ever before.

Explore further: Telecommunications expert suggests Earth may have dark matter disc

More information: Dark Matter as a Trigger for Periodic Comet Impacts, Phys. Rev. Lett. 112, 161301 – Published 21 April 2014. journals.aps.org/prl/abstract/… ysRevLett.112.161301

ABSTRACT
Although statistical evidence is not overwhelming, possible support for an approximately 35×106  yr periodicity in the crater record on Earth could indicate a nonrandom underlying enhancement of meteorite impacts at regular intervals. A proposed explanation in terms of tidal effects on Oort cloud comet perturbations as the Solar System passes through the galactic midplane is hampered by lack of an underlying cause for sufficiently enhanced gravitational effects over a sufficiently short time interval and by the time frame between such possible enhancements. We show that a smooth dark disk in the galactic midplane would address both these issues and create a periodic enhancement of the sort that has potentially been observed. Such a disk is motivated by a novel dark matter component with dissipative cooling that we considered in earlier work. We show how to evaluate the statistical evidence for periodicity by input of appropriate measured priors from the galactic model, justifying or ruling out periodic cratering with more confidence than by evaluating the data without an underlying model. We find that, marginalizing over astrophysical uncertainties, the likelihood ratio for such a model relative to one with a constant cratering rate is 3.0, which moderately favors the dark disk model. Our analysis furthermore yields a posterior distribution that, based on current crater data, singles out a dark matter disk surface density of approximately 10M⊙/pc2. The geological record thereby motivates a particular model of dark matter that will be probed in the near future.

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no fate
3.4 / 5 (10) May 01, 2014
"This new theory by the research pair has some problems"

Invoking Dark matter for starters.
What other purturbations support this hypothesis? Surely there are other "inferred" examples of interaction with the disk besides comet strikes in our solar system. What are they? Why is the disk smooth when all of the rest of the "gravitationally" influenced matter crosses the plane at cyclical intervals?

The continued existence of the galaxy and comet strikes with a semi accurate estimate in periodicity are not evidence of DM...unless you really really really want them to be..then they can be.
what_the_hell
2.9 / 5 (13) May 01, 2014
Dark matter. Pssh.
RandallSnyderJr
3.5 / 5 (8) May 01, 2014
"No matter how well liked a theory may be, if observation contradicts it, then it must be rejected. For science to be useful, it must provide an increasingly true and deep description of what nature must be." ~ Eric J. Lerner
TheGhostofOtto1923
2.2 / 5 (5) May 01, 2014
Hey barakn wasn't I just talking about this? We have only recently become able to detect potential impactors. But this does not mean that we are not witnessing a surge in the number of them.
chardo137
5 / 5 (6) May 01, 2014
The authors are well aware of the assumptions that they are making. PDF of the paper an arXiv: http://arxiv.org/...0576.pdf
no fate
1.8 / 5 (5) May 01, 2014
The authors are well aware of the assumptions that they are making. PDF of the paper an arXiv: http://arxiv.org/...0576.pdf


The paper:"Sun, as it orbits the Galactic Center, oscillates up and
down through the plane of the galaxy, leading to periodic
perturbations of the Oort cloud from enhanced density
near the plane."

This hypothesis isn't observed with baryonic matter, hence the proposal for the DM disk. However DM, as a source of gravity, should behave the same as the other sources of gravity in a model based on gravitation and thus, oscillate through the plane along with the rest of the matter. They hypothesize not only that it doesn't, but that it must be a "species" different from the other DM we haven't found yet in order to form the disk.
How can a disk of matter which exerts a gravitational force NOT be subject to the same gravitational forces which influence the motion of all of the matter in a region? If the disk is there, why doesn't it oscillate as well?

barakn
4.2 / 5 (6) May 01, 2014
Hey barakn wasn't I just talking about this? We have only recently become able to detect potential impactors. But this does not mean that we are not witnessing a surge in the number of them.

Yes, indeed we were. But since it takes millenia to pass through even a "thin" dark matter disk, I don't think it can explain dramatic changes in meteorite/asteroid impacts on the order of a few years.
SnowballSolarSystem _SSS_
1 / 5 (6) May 01, 2014
I wouldn't wonder that the dark-matter Bok globules in the spiral plane have an effect, but I have a model for extinction level events caused by Sedna-sized icy-body impacts which contribute continental land mass in the form of aqueously-differentiated rock.

I suggest that the similar arguments of perihelion of extended scattered disk (also called inner Oort cloud) TNOs planetesimals and dwarf planets are not aligned by a _current_ Planet-X as supposed, but rather a _former_ Companion star to the Sun that has 'recently' drifted away.

When extended scattered disk TNOs and dwarf planets and Oort cloud comets further out mutually cross the orbit of our former Companion, their orbits change from barycentric to heliocentric and back again, providing the perturbation mechanism.

Now with the loss of the Companion and its concomitant centrifugal force of the Sun around our former solar-system barycenter, we may be transitioning from an era dominated by icy-body impacts from the outer sol
TheGhostofOtto1923
3.3 / 5 (6) May 01, 2014
subject to the same gravitational forces which influence the motion of all of the matter in a region? If the disk is there, why doesn't it oscillate as well?
You know, I bet this very question, among many others, occurred also to the researchers, who are after all experts, who did the paper. Why dont you read it and find out?
I don't think it can explain dramatic changes in meteorite/asteroid impacts on the order of a few years
But, AGAIN, we wouldnt know until you actually saw the data now would we? The authors do say this:

"...sufficiently enhanced gravitational effects over a sufficiently short time interval and by the time frame between such possible enhancements. We show that a smooth dark disk in the galactic midplane would address both these issues"

-I suppose it would depend on what they mean by 'short'. Depending on how thin and dense this disk is, the effect could possibly be similar to that of a large perturbing body. The transition could be quite abrupt.
no fate
3.4 / 5 (5) May 01, 2014
"You know, I bet this very question, among many others, occurred also to the researchers, who are after all experts, who did the paper. Why dont you read it and find out?" - Goo

I did. It didn't. Perhaps you can point out where you think they address it since you seem to think they have. Or were you being deliberately obtuse in the hope that I hadn't read the paper even though I quoted part of it above?

Pejico
May 01, 2014
This comment has been removed by a moderator.
Shitead
1 / 5 (3) May 01, 2014
The periodicity for passing through the galactic plane is not 32 or 35 my.; it is currently 26.6 my. (subject to gravitational damping). The perturbation of each passage on the Oort cloud produces a Poisson distribution of comets moving toward the sun, occasionally with devastating effects on planet Earth.
Whatever the cause of these gravitational perturbations (call it dark matter for sake of argument) it appears to produce a number of other effects on Earth; extreme vulcanism producing Large Igneous Provinces, hot spots that produce chains of volcanoes for millions of years, and surges of speciation (in those species that are not driven to extinction).
Interestingly, most passages through the galactic plane don't seem to do much of anything, but sometimes all hell breaks loose.
Pejico
May 01, 2014
This comment has been removed by a moderator.
Pejico
May 01, 2014
This comment has been removed by a moderator.
g_g_kanev
1 / 5 (6) May 01, 2014
About Lisa Randall and Matthew Reece idea and is it possible to achieve dark matter identification?
This is very interesting idea, which can realize indeed after the precise maps of our galaxy especially the orbital velocities and positions of the stars and I should add also the radial velocities of the stars, which I'm convinced that exist. About the dark matter I believe we can observe it right now, because according to USM www.kanevuniverse.com]www.kanevuniverse.com[/url] the so called relict radiation in fact is radiation by the sub stars from the subspace where the atoms (nuclei) in our space do represent the galaxies in the subspace including the young sub galaxies which are born in the center of our galaxy and called proto particles. See this: I believe that this experiment (south-pole radio telescope experiment) has huge potential and will be correctly to continue further. I propose the following experiment: The idea is to see (how it is possible of course) whether in the frequencies which are responsible about the galactic dust, exists some "red shifting" (low frequency part thickening) and to compare such eventually shifting about the main observed radiation. Because about the close to us (as a observers - radius position of our Sun in the galaxy) dust, such shifting shouldn't exist (we are shifting together with this dust towards the periphery of the galaxy), but if we discovery such shifting in the main radiation, this will be direct evidence that the observed radiation comes from the proto particles, which in fact represent the galaxies from the sub space, which shouldn't shift compared to the stars (including our Sun). Actually what is observed as a radiation reminds a lot the "universe" of the sub space, which is similar to our universe if we can look it from above!
Finally I have only one notice about the quantity of the dark matter in the galaxy and see this: Nice experiments, but lack of correct ideas, which is understandable because obviously the author don't familiar with the Undivided Structure of the Matter USM www.kanevuniverse.com]www.kanevuniverse.com[/url] Namely: The unity and essence of the fields (gravitational electrostatic-magnetic and nuclear ones), which is shown convincingly in USM. From this follows that all the fields are the same which appears in between nuclear space like a nuclear, in between atoms space like electrostatic and in between galaxy space like gravitational one. How is created and what is the essence of the magnetic field also is shown in very convincing way. Moreover in very important analysis is shown the inertial character of this unity field, which by one very simple way explain the expansion of the over space and its acceleration, which is not absolutely but only for us and only for our galaxy radius-position of our Sun. It is truth that the galaxies aren't form their shape by the some black hole in the center or the so called dark energy indeed exist, but the galaxy gravitational field is creates through inter movement between the galaxies themselves how it is shown on USM. This defines the rotation centripetal forces of galaxy and forms its shape by analogy with the atoms quantum action, which is means that this forces attract only part of the galaxy matter, where are birth the stars little centrally area with the radius around 10 rising to a 12 power times smaller than the present orbital radius of the Sun and only about the first moment of stars formation. The rest of the galaxy matter is disperses by inertial way. That is why the tangential velocity of the galaxy matter remains almost constant with galaxy radius increasing, but not because of the so called dark matter, which play little role of this velocity decreasing and therefore this mass is far more little than previously estimated. G.Kanev
TheGhostofOtto1923
3.7 / 5 (6) May 01, 2014
I did. It didn't. Perhaps you can point out where you think they address it since you seem to think they have
No I didnt read the paper but I do assume that harvard researchers possess a minimum level of competence. Agreed?

What could possibly make you think that the questions that occur to YOU after spending only a few minutes reading a news release, which are after all pretty freeking OBVIOUS and fundamental questions, wouldnt have occurred to harvard researchers who have spent months writing their paper?

And what makes you think you can ask questions like THAT, without having even bothered to read the paper first, without getting freeking TRASHED for it?
GuruShabu
3 / 5 (2) May 01, 2014
Nonsense over nonsense.
Pejico
May 01, 2014
This comment has been removed by a moderator.
Uncle Ira
1.9 / 5 (9) May 01, 2014
G.Kanev


G.Knave-Skippy, can you explain that again using normal words? Why you Einstein wannabes think if you say something nobody can understand that everybody or somebody might be fooled into thinking you are one of the smart peoples?

All the really smart peoples can say the things so that other people can understands them. Did you know that Cher? It is true, mon ami, if nobody understand what you say it is a sure sign that everybody is smarter than you, eh?

That's why the Skippys like you are get a silly looking pointy cap to wear for the smart peoples to make fun with. You are got yourself on the list Knave-Skippy, bad karma points for you to go with that silly looking pointy cap on your head that looks so apropos on you Cher.
Uncle Ira
2.2 / 5 (9) May 01, 2014
Kanev, your opinions have many valid points (in certain extent they're actually overshooting my own ideas, so I cannot agree with them in full depth), but they're still not so smart for being relevant to the discussion subject at least partially. The off-topic posts dilute the coherence of discussion and its relevance for understanding - no matter how insightful they actually can be in another context. Got it?


@ Zephir-Skippy how you go Neg? That Knave-Skippy is stealing your ideas, eh? The johnpringles-Skippy been stealing them too him over on the paradoxing twin conversations.
Pejico
May 01, 2014
This comment has been removed by a moderator.
Uncle Ira
2 / 5 (9) May 01, 2014
The inherent property of silly and uninformed people is, they cannot understand more complex ideas. I do understand, what Kanev wanted to say - but from the same reason I can tell safely, it doesn't contribute with anything to the current subject. For example the insight, that the metric expansion of space applies only to local observer fits well with my water surface analogies/explanations of the red shift. It can serve as a strong http://www.scienc...ox-85942 scenario in future. But I cannot agree, that the gravity field of galaxies is modeled with the external galaxies - it applies to cold dark matter only. And many other insights are exaggerated in similar way.


@ Zephir-Skippy it sounds a lot smarter the way you say it for me it does. You must be finally making way against the current, eh? That's two peoples in one day stealing your ideas.
Pejico
May 01, 2014
This comment has been removed by a moderator.
Pejico
May 01, 2014
This comment has been removed by a moderator.
rockwolf1000
5 / 5 (6) May 01, 2014
Kanev, your opinions have many valid points (in certain extent they're rather overshooting my own ideas, so I cannot agree with them in full depth), but they're still not so smart for being relevant to the discussion subject at least partially. The off-topic posts dilute the coherence of discussion and its relevance for understanding - no matter how insightful they actually can be in another context. Got it?


@ Zephyr
No one, and I mean no one, goes on off topic rants more than you my friend. It simply doesn't matter what topic is being discussed; you find a way to insert AWT or cold fusion or any of your other pet theories into the thread. I think you're a pretty smart guy but you gotta watch who's calling the kettle black!
Pejico
May 01, 2014
This comment has been removed by a moderator.
Caliban
5 / 5 (3) May 01, 2014
But the central question remains: Why is it necessary to invoke some hypothesised exotic species of DM to produce the gravitational perturbation of objects in the Oort Cloud?

Wouldn't the mere physics of passing through a region of greater mass density --and therefore gravitational force-- be sufficient to produce this effect upon objects that were not only in the OCloud, but that might also just be interpenetrating the solar system?

We pass through the galactic disk simultaneously with its passage through us.

Pejico
May 01, 2014
This comment has been removed by a moderator.
Returners
1 / 5 (5) May 01, 2014
How can a disk of matter which exerts a gravitational force NOT be subject to the same gravitational forces which influence the motion of all of the matter in a region? If the disk is there, why doesn't it oscillate as well?


Conjecture 1:
Massless particle nevertheless exerts gravitational force proportional to it's energy level.
Plausibilty: Low, but non-zero.
Problem: Why doesn't it escape the galaxy and diffuse through space?

Conjecture 2:
The "disk" or "halo" is an imaginary construct invented to explain a mis-understanding of Newton's law of gravity, for example, failure to realize a non-zero constant of integration (anti-derivative, not necessarily integral,) is in fact a valid solution to the anti-derivative of the acceleration formula, thereby explaining the flat stellar orbital velocity curve without the existence of a mysterious substance. Nobody even addresses this issue.

A non-zero constant of Integration is in fact a valid solution. Now plot that...
Uncle Ira
2.1 / 5 (8) May 01, 2014
Conjecture 1:
Massless particle nevertheless exerts gravitational force proportional to it's energy level.
Plausibilty: Low, but non-zero.
Problem: Why doesn't it escape the galaxy and diffuse through space?


Do you have a name for that theory Returnering-Skippy? Or is it something you pull from your butt Cher?

Conjecture 2:
The "disk" or "halo" is an imaginary construct invented to explain a mis-understanding of Newton's law of gravity, for example, failure to realize a non-zero constant of integration (anti-derivative, not necessarily integral,) is in fact a valid solution to the anti-derivative of the acceleration formula, thereby explaining the flat stellar orbital velocity curve without the existence of a mysterious substance. Nobody even addresses this issue.


Returnering-Skippy, even ol Ira knows they addresseded that issue.

A non-zero constant of Integration is in fact a valid solution. Now plot that...


Why you don't plot it yourself there Skippy?
Pejico
May 01, 2014
This comment has been removed by a moderator.
Returners
1 / 5 (3) May 01, 2014
Why you don't plot it yourself there


It produces a slope zero line.

Mre accurately, it shifts the hyperbolic curve of escape velocity upward or downward, but with the limit as r-> infinity being proportional to the constant itself (zero assumed presently,) and then in turn would shift the escape velocity of objects in a system upward or downward.

now if you go back and take a look at that stellar orbital velocity curve and see that it levels out and stays flat, the notion of a hidden constant/semi-constant term in the gravity equation starts to look attractive. It looks like a hyperbolic curve shifted upwards:

y = -GM/r + C

Put that in a graphing calculator or software.

Curve "B", seen in the link, is almost an exact solution in the family "y=-GM/r +C", where C in this case is a positive constant.

http://en.wikiped...ion2.svg

As r gets very big, -GM/r approaches zero, and the curve approaches "C" and stays there.

Viola. An exact match.
Returners
1 / 5 (3) May 01, 2014
When you are taught calculus and differentials, it is mentioned a few occasions that values for C (sometimes used K) of non-zero are valid solutions, but because most of the time you're doing a full integral it is assumed the constant cancels itself. However, in the real universe, because "information" is limited by the speed of light, the notion of "information" canceling itself during physical, universal equivalent of an integration is inherently flawed: since "information" can't get from one end of the curve to the other in instantaneous time, it cannot necessarily "cancel" itself, thus a residual constant conceivably can remain either way.

Again, you are taught that these are valid solutions to the antiderivative.

However, in normal science and engineering the constant is always assumed to be zero. This is not necessarily a sound assumption. A valid solution is still a valid solution, even if you think it's over-complicated.
Pejico
May 01, 2014
This comment has been removed by a moderator.
Returners
1 / 5 (3) May 01, 2014
So notice, "Y = -GM/r +C" is a negative hyperbolic, shifted upward, which is almost exactly what you see in the curve B on the stellar orbital velocity curve.

The stellar orbital velocity curve is a negative hyperbolic, and is shifted upward by a constant.
The generalized antiderivative of the gravity acceleration formula is a negative hyperbolic curve shifted by a constant.

The two have exactly the same order, so an arbitrary constant, K, (for lack of confusion with c used for speed of light,) fixes the problem exactly, and falls well within the laws of mathematics.

I've pointed this possible explanation out before, and get ridiculed for it, but there is no mathematical reason to discard this solution. It's a very basic and obvious and easily obtainable solution within the known laws of physics, without proposing phantom particles and phantom forces.
Benni
2.6 / 5 (5) May 01, 2014
"....if nobody understand what you say it is a sure sign that everybody is smarter than you, eh?" Uncle Ira

@ Uncle Ira: You keep up the constant prattle about others moving over & making room for listening to "the smart people" posting here. Your posts are among the most frequently appearing of any that appear in this forum taking up a lot of space that could otherwise be allotted to those who sincerely would like to have scientific discussions with others......that is others of those who are of like mind which you obviously are not......so why don't you simply cease with the unintelligible prattle & noise & and make a serious attempt at discussing science with us, or GET OFF THE FORUM.
Uncle Ira
1.5 / 5 (8) May 01, 2014
So notice, "Y = -GM/r +C" is a negative hyperbolic, shifted upward, which is almost exactly what you see in the curve B on the stellar orbital velocity curve.


I just try to check out what you think know and run up on a problem with this, and if this a piece you got the very wrong then everything that come before and after it is wrong too Cher.

Ol Ira-Skippy found that the google-Skippy says you don't know what you talking about Returnering-Skippy. The google-Skippy says that thing you write there is not the right way to write the hyperbolic anything. So you just making this up out of your butt there Skippy-Doo.

I tell to see before that they already considered these issues. The found out that it wouldn't work the Returnering-Skippy thinks without making the big problem somewhere else. They called it mond theory or some such a thing.

Put the silly looking pointy cap back on Skippy. I tell you yesterday there is a lot of things I don't know me, but I am not so stupid.
Uncle Ira
1 / 5 (7) May 01, 2014
@ Benni-Skippy You don't see me here trying to talk about the science?

I got the silly looking pointy cap for you too if you want it you. Now you can get away yourself Cher, you have got my attention p'tit boug. Don't make me the misere you, I am not always so good nature me.
Bob Osaka
2.8 / 5 (4) May 02, 2014
You guys comparing the size of your slide-rules again?
For communication, simple is best.
The Earth spins, ionosphere, can't see it but trust me it's there.
The sun spins, heliosheath, can't see it but if you trust Voyager 1 and 2 heliopause.
The SMBH spins, galactic current sheet theorized.
Earth's magnetic field extends in a distance relative to its mass. The sun same thing at 122Au,
that is one hundred twenty-two times greater than the Earth's distance from the sun.
The Milky Way's, (our) super massive black hole SMBH has an estimated mass 2 to 4 million solar masses. (maybe more but probably not less) How far do you think the galactic sheath extends? Should not it have already been interacting with Andromeda's throughout human history? What kind of space/time, gravitational lensing distortions could such interaction cause?
I've said it before, dark energy/matter are perfect analogies for our ignorance and propensity to act on nonsense.
Know now how to use your slide-rule?
Writela
1 / 5 (2) May 02, 2014
The existence of dark matter has many things in common with (dismissal of) tired light model. The mainstream physicists have apparent problem with understanding of emergent phenomena, which are on the verge of particle and field concept (scalar waves). IMO both dark matter, both red shift are caused with density fluctuations of vacuum (space-time curvatures), which are relatively large but very short-living and subtle. Whereas both life-time both size of common particles is substantially smaller, than the wavelength of light, in which we are observing them. For deterministically thinking physicists these fuzzy artifacts are difficult to describe mathematically so that they tend to ignore them as a whole, despite their collective effects are quite pronounced. In analogy with water surface model of space-time it just means, the physicists ignore all waves and underwater turbulence, which cannot be described like the well defined deterministic ripples and solitons.
SnowballSolarSystem _SSS_
1 / 5 (1) May 02, 2014
The Universe(U) after the Big Bang is governed by phase changes & symmetry breaking.

After the Dark Ages w/the appearance of atomic hydrogen(H), U reionized--why?

As U cooled, gravity pooled H, forming the galaxy-sized masses, largest to smallest and as cooling allowed progressively smaller masses to become gravitationally bound.

Compressing gas raises T, reconverted most of the H into ionized gas--not uniformly but at nucleation centers like supersaturated air nucleating on dust and pollen particles condensing into droplets forming clouds.

Ionization of H is endothermic, clamping T, allowing densification of plasma into spheres--'globules'. The largest collapsed into Pop III stars>>black holes>>central supermassive black holes.

Globules of pure H <100 stellar masses can't collapse into stars without additional mass, pressure or metallicity, so they persist in gravitationally-bound globules & cooled by evaporation to form the coldest objects in the U

Bok globules = dark matter
TheGhostofOtto1923
3 / 5 (4) May 02, 2014
I got the silly looking pointy cap for you too if you want it you. Now you can get away yourself Cher, you have got my attention p'tit boug. Don't make me the misere you, I am not always so good nature me
I think bennis sentiments are best expressed in song.
http://youtu.be/IU03uD5PTG4
IMP-9
5 / 5 (4) May 02, 2014
Bok globules = dark matter


How would such dense objects form? Why aren't they observed in the galaxy in great numbers? Why wouldn't galaxies much much brighter in the far infrared and submilimeter where globules emit? How would globules survive the densest regions of galaxies without merging or begin accreted? How would they survive cluster mergers? How could they explain cluster dynamics when the intracluster medium is millions of degrees, which couldn't support cool globules? How does that explain nucleosynthesis which does not agree that DM is baryonic? I'd say globules don't fit.
IMP-9
5 / 5 (3) May 02, 2014
y = -GM/r + C


That's nothing but a fudge. If there was truly some constant like this why does the solar system follow Kepler's laws which have no constant? Why do earth satellites not need the constant?

You need to label your equation correctly. GM/r is the potential field, adding a constant to the potential field does nothing, only the gradient causes acceleration. Your equation is meaningless.
Uncle Ira
2 / 5 (4) May 02, 2014
y = -GM/r + C


That's nothing but a fudge. If there was truly some constant like this why does the solar system follow Kepler's laws which have no constant? Why do earth satellites not need the constant?

You need to label your equation correctly. GM/r is the potential field, adding a constant to the potential field does nothing, only the gradient causes acceleration. Your equation is meaningless.


Thanks for that IMP-Skippy. I thought I was reading the google right where it said that thing Returnering-Skippy wrote didn't mean what he said it means.
Benni
1 / 5 (4) May 02, 2014
@ Benni-Skippy You don't see me here trying to talk about the science?


............just my point, at least you get that part..........now try discussing with us Einstein's use of partial differential equations by which he proved in his General Theory of Relativity that the universe is of quasi-spherical geometry. Do think you can go there with me & your sharp "pointy" pencil?
Uncle Ira
2 / 5 (4) May 02, 2014
.now try discussing with us Einstein's use of partial differential equations by which he proved in his General Theory of Relativity that the universe is of quasi-spherical geometry. Do think you can go there with me & your sharp "pointy" pencil?


@ Benni-Skippy I thought this one was about the dark matter disk. I never claim to be the scientist non, I am only the engineer man. Are you trying to say to me that you actually could understand what the Knave-Skippy was talking about? Was that what thing he was hinting at, the Relative quasi-spherical geometry? Or were you going off the topic with that trying to trick me?
Benni
1 / 5 (4) May 02, 2014
.now try discussing with us Einstein's use of partial differential equations by which he proved in his General Theory of Relativity that the universe is of quasi-spherical geometry. Do think you can go there with me & your sharp "pointy" pencil?


@ Benni-Skippy I thought this one was about the dark matter disk. I never claim to be the scientist , I am only the engineer man. Are you trying to say to me that you actually could understand what the Knave-Skippy was talking about? Was that what thing he was hinting at, the Relative quasi-spherical geometry? Or were you going off the topic with that trying to trick me?


..........nope, partial differential equations are not a trick, they're the language of my job description as a Nuclear/Electrical Engineer. I'm just trying to do my part eliciting scientific thought in locating the Missing Dark Stuff that composes 90+ % of the Universe that Einstein's calculations predicted must exist to account for all that gravity.
Uncle Ira
2 / 5 (4) May 02, 2014
..........nope, partial differential equations are not a trick, they're the language of my job description as a Nuclear/Electrical Engineer. I'm just trying to do my part eliciting scientific thought in locating the Missing Dark Stuff that composes 90+ % of the Universe that Einstein's calculations predicted must exist to account for all that gravity.


Well when you find it will cut ol Ira-Skippy in? After all the hooraheeing about the dark matters last the couple years, you going to make yourself a big bundle for finding it. Who ever find it first will probably get richer than Bill Gates.
Uncle Ira
1.8 / 5 (5) May 02, 2014
@ P. S. for you Benni-Skippy I am the engineer man too me. On the towum / pushum boats, on the Mississippi and on the Ohio rivers. But we don't have the different equations for that, we just use the normal ciphering.
no fate
1 / 5 (2) May 03, 2014
I did. It didn't. Perhaps you can point out where you think they address it since you seem to think they have
No I didnt read the paper but I do assume that harvard researchers possess a minimum level of competence. Agreed?

What could possibly make you think that the questions that occur to YOU after spending only a few minutes reading a news release, which are after all pretty freeking OBVIOUS and fundamental questions, wouldnt have occurred to harvard researchers who have spent months writing their paper?


Not agreed. If you want to discuss the paper and what it does and doesn't address, read it. Then we can talk about it without you having to wrongly assume a level of competence not evident in the work. Were you on the review committee for this paper? Might explain how it made it into a journal without addressing this portion of the physics...you know, by assuming it all works out.

Trashed? Not by your assumptions I'm afraid.
Benni
1 / 5 (4) May 03, 2014
@ P. S. for you Benni-Skippy I am the engineer man too me. On the towum / pushum boats, on the Mississippi and on the Ohio rivers. But we don't have the different equations for that, we just use the normal ciphering.


You are a Phys.Org Moderator who does a very sloppy job of it. Your voting record has always given away how little you know about science, while demanding of others what you yourself are innately incapable of.

Your posting apps are simply a diversionary technique which only function to drive away those who want to discuss serious issues of science, once again you give this away with your voting record.

I have young children, and I know far better than you how derisive comments (usually unintended) affects how they respond to me in kind. Your voting record & linguistic apps as a Moderator reveal what you truly believe about Phys.Org being a competent science forum, the evidence is that you really don't care & Phys.org needs to replace you.
Uncle Ira
1.8 / 5 (5) May 03, 2014
@ Benni-Skippy are you taking drugs or some thing? I been called the idiot and the troll and the moron and other things what I can't remember right now. But I have never been called the Moderator. My record for the voting don't give nothing away more than who I think are nice peoples and who I think are not so nice peoples. You cross peoples who you like you? You cross peoples who you don't like you? That should not be so hard for someone who wants to be nucleus engineer man to understand.
Pejico
May 03, 2014
This comment has been removed by a moderator.
Steve 200mph Cruiz
2 / 5 (2) May 04, 2014
This is a good postulation, what I think what we really need above all else is an accurate measurement of the Oort cloud including its temperature, but more importantly, its shape (including distance) and it's density.

Many objects in the solar system past the Kuiper belt have a higher orbital eccentricity, I suspect this pattern can be reflected outwards towards the rest of the solar system, including the Oort cloud. Not only is the density of the Oort cloud important for determining the chances of an impact are, an eccentric halo would be more gravitationally unstable as well, producing more impacts here on earth. The effect of this measurement could then be applied to the rate of major gravitationally disrupting events with in our local area (odds of stars getting close to each other, traveling through nebula, ect.) and on a galactic level as well, such as this dark matter hypothesis. This would give us a way to measure the mass of the dark matter disk as well.
no fate
2.7 / 5 (3) May 05, 2014
"Actually the people who understand the physics up to level, which enables them to see the holes in existing theories are regularly downvoted more, just because they managed to criticize them. Only dumb sheep cannot see anything outside of well established facts from textbooks. If some thing the oxen hate the most, it's just the fact, that someone is smarter then they are. So you can really use the voting status as an indication of actual intelligence of posters here, just in inversed way." - Zeph

Well said, It doesn't go unnoticed by other people than "the regulars". Seeing a bunch of 1's beside a valid comment, if they are from that group (a friend referred to them as the hall monitors), show personal bias. Guess where that gets you in the scientific community...besides unlimited time to "patrol" Physorg.com.....