Telecommunications expert suggests Earth may have dark matter disc

Jan 03, 2014 by Bob Yirka weblog
Credit: NASA

Ben Harris, a telecommunications and GPS satellite expert with the University of Texas has made a surprising announcement during his presentation at this year's gathering for the American Geophysical Union. He reported that using GPS data to calculate the mass of the Earth, gives a slightly bigger number than is accepted by the International Astronomical Union. The difference, he suggests, may be due to a disc of dark matter that exists over the equator.

Dark matter is of course the mysterious stuff that physicists have come to believe exists all throughout the universe. We can't see it, but researchers have managed to sense its presence in a variety of ways (such as measuring its gravitational impact on stars, other planets, etc.). In so doing, most in the field have come to believe that it makes up approximately 80 percent of all matter. Unfortunately (mainly because it doesn't appear to absorb or emit light or ) none of the studies done so far have been able to prove that truly exists—thus, the search goes on for some new kind of method to prove that dark matter isn't just a theory, or alternatively, for some other explanation of what has been observed.

Among other studies, back in 2009, it was noted that space probes passing by Earth experienced unexplainable slight changes in velocity, which some have attributed to them encountering dark matter. It could not be proven of course, but then there weren't any other explanations for it either.

In this new effort, Harris collected data from several satellite groups (European Galileo, U.S., GPS, GLONASS and Russian), which he then used to measure the mass of the Earth—a process which he describes as calculating by "feeling" the pull on each satellite. In so doing, he reports that his calculations were between 0.005 and 0.008 percent greater than that described by the IAU. The difference, he said, could be explained by a very large disc of dark matter over the equator.

Harris's theory doesn't take into account changes in orbits of satellites that occur because of relativity, or the impact of gravity from the sun and moon, thus it's still very preliminary. If other studies confirm what he's found however, there exists the possibility that satellites could one day be used to not only prove the existence of , but to measure it in a very accurate way.

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More information: via New Scientist

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cantdrive85
Jan 03, 2014
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loneislander
4.2 / 5 (9) Jan 03, 2014
Ok, what's wrong with my math here?

If it's 0.005-8 percent different than we take the mass of the earth and divide by 0.00005 to find the approximate size of the excess mass? That's 3 x 10^17 metric tons (the moon is 7 x 10 ^ 19). That's a whopping error -- how come we don't see satellites jumping around up there like the retrocycles of ye olde days (pre Kepler)? (I gotta be missing something obvious).
ekim
Jan 03, 2014
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Zephir_fan
Jan 03, 2014
This comment has been removed by a moderator.
Zephir_fan
Jan 03, 2014
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tadchem
4.6 / 5 (17) Jan 03, 2014
"Harris's theory doesn't take into account changes in orbits of satellites that occur because of relativity, or the impact of gravity from the sun and moon"
When I was in school I got no credit for incomplete homework.
vpoko
4.8 / 5 (6) Jan 03, 2014
How accurately can we take the sun and moon into account? I thought our ability to do that is limited by the three-body problem?
shavera
5 / 5 (11) Jan 03, 2014
vpoko: the three body problem is only that we can't find *analytical* solutions to Newtonian physics. We can do numerical ones to pretty high precision.

In general... Conference presentations are not at all the same as a published paper. It may be a *hint* of future science, but we should all take it with 3 x 10^17 metric tons of salt (double checked loneislander's math because you multiply by .00005, not divide. Their words were just incorrect)
JIMBO
3.9 / 5 (7) Jan 03, 2014
Sorry, it doesn't hold water. Recently, independent searches for DM present in the solar system have convincingly come up null. Hard to believe that DM could be clustering around Earth, but not elsewhere. Not to mention, 50-80 ppm measmt. error in the mass of the earth is not going to convince anyone.
KhanneaSuntzu
2.3 / 5 (6) Jan 03, 2014
Metaphysical, spiritual concepts.
MRBlizzard
3 / 5 (2) Jan 03, 2014
A while ago, a colleague mentioned to me that JPL's General Relativistic model for our Solar System contained a best fit background, gravitational field. I don't see why this couldn't be the result of a light year scale, dark matter stream near our solar system. By stream, I am alluding to streams of stars in the Milky Way arising from smaller galaxies being taken in by the Milky Way. Yes, the Earth is much, much smaller; however, the mass of the Earth is unknown. What we work with is GxM (gravitational constant times mass of the Earth). That stays pretty constant, but we don't know the value of G. So the estimate of the Earth's mass changes by values larger than 10^17 metric tons.

2. Where can I get the whole paper?
davidivad
4 / 5 (2) Jan 03, 2014
the velocity of an object in orbit must be around 17-18 thousand miles per hour. it seems one could easily deduce the mass of such a particle to see whether it fits the data we have so far for dark matter. anyone for a quick google and a calculator?
indio007
1.8 / 5 (6) Jan 03, 2014
Anything to save Einstein ... again... with dark matter mysticism.

GPS does not verify relativity.

RON HATCH: Relativity in the Light of GPS
http://www.youtub...1GU_HDwY
antialias_physorg
3.7 / 5 (7) Jan 03, 2014
Well, one might be able to check that: Look at effects of probes we have circling other planets. If present these should have dark matter halo effects proportional to their respective masses.
(The relativistic effects and other gravity sources not accounted for in the study should be included first).

Venus Express is orbiting Venus. Akatsuki may be orbiting it, too, in 2016. (And there might be relevant data from the old Magellan and Venera 15/16 missions)
There should be data from Cassini from its Saturn orbits.
Grail A/B, the Chang'e and ARTEMIS missions for the Moon
...and of course the shitload of orbiters that we had/have around Mars.
HannesAlfven
2.4 / 5 (15) Jan 03, 2014
Mainstream science has NO PLAN for what it will do in the event that dark matter does not exist, and this leads to increasingly desperate claims that it does. Physicists should actually be alarmed that there is no existing system for innovating new, divergent ideas in their discipline. All new ideas get shot down due to a failure in "accuracy". But, this never-ending focus upon having accurate models before the models even ever get a chance to be constructed is a very public demonstration that conventional science does not actually understand how innovation occurs in other disciplines -- like graphic or product design.

What's happening today in science is actually quite embarrassing to watch. Specialization creates people who fail to see the big picture, and then society thinks they can ask them big questions.

It's a total mess, guys. There are no answers at the end of this path. If we cannot shake ourselves from these mistakes, the legacy will be unfortunate.
shavera
4.7 / 5 (3) Jan 03, 2014
MrBlizzard: There is no paper (that I can find), it's only a conference presentation. This is a place to remain skeptical.
HannesAlfven
2.5 / 5 (11) Jan 03, 2014
Physics education researchers like Eric Mazur and David Hestenes have been begging university physics professors for a couple of decades now to introduce metrics into their instruction to reveal just how much conceptual comprehension is occurring for students in university physics courses. The professors have thus far resisted the introduction of these measures. This is a huge red flag, people, that there is a very serious problem happening at the level of concepts in physics instruction.

And where you see evidence for conceptual confusion in student comprehension, we can expect to follow the trail to the scientific models themselves. People think they can problem-solve their way out of this because that's how they were taught. But, if you look at what we've learned over the past couple of decades about physics instruction, it becomes obvious that we should be taking a closer look at the concepts themselves.
HannesAlfven
2.5 / 5 (11) Jan 03, 2014
Conceptual confusion predictably leads to an inability to spot mistakes in models. These problems are compounded by the "textbook perspective" to the world -- which goes out of its way to omit points of contention for the current popular models. There are many controversies today which the graduate students never even hear about.

You guys think that you will solve the most complex questions mankind has ever asked with this approach?

Keep living the dream. But, don't be surprised when somebody swings in with a superior vision for how to solve these problems. Be prepared for the worst case scenario, that quite possibly most of these models are going to run into a dead end, and students of the future will be taught the concept of dark matter in just a few short sentences, and within the context of mistake.

Doubling down each time you fail comes with the possible consequence that you've been wasting everybody's time and money.
big_hairy_jimbo
4.7 / 5 (6) Jan 03, 2014
Did he take into account that the Earth is an oblate sphere, a geoid?
The Earth is not uniformly dense.
Benni
1 / 5 (3) Jan 03, 2014
If Dark Matter, composes 80% of all matter in existence as suggested in the article, it then follows that the globe we see from orbiting satellites is only 20% of all the matter that composes the entirety of that which we can view & have labeled "Earth".

The suggestion proposed in the article is that a 0.005 - 0.008% greater gravitational pull than expected was discovered by his calculation. That's not much gravity considering that we supposedly cannot see the remaining 60% of Earth's total mass (80% total mass minus the 20% visible mass= 60% DM). Of course I am assuming dark matter is evenly distributed throughout the universe, which obviously in the case of Moon, Mars & Venus the same even distribution rule must apply because we've landed probes using visible mass gravity calculations. So wherever all this DM is, we're not finding it inside our solar system.
Zephir_fan
Jan 03, 2014
This comment has been removed by a moderator.
Gigel
5 / 5 (7) Jan 03, 2014
If Dark Matter, composes 80% of all matter in existence ...


DM is not assumed to be evenly distributed in the universe, otherwise the notion of a DM disc would be nonsense.
baudrunner
1 / 5 (8) Jan 03, 2014
Unfortunately (mainly because it doesn't appear to absorb or emit light or electromagnetic radiation) none of the studies done so far have been able to prove that dark matter truly exists
I keep saying, but nobody wants to listen, DARK MATTER IS HELIUM. Helium cannot be seen, and does not absorb or emit light or electromagnetic radiation, therefore Helium has no permittivity to light propagation.

It should be a simple matter to test this using a helium capture device that filters hydrogen and blocks higher elements, if such a thing were possible to create, which it no doubt is. Fill a transparent balloon with 100% PURE helium and see what you get. Black.
Torbjorn_Larsson_OM
4.2 / 5 (5) Jan 03, 2014
At first glance it looks like a crap calculation with phony precision (because the static mass isn't as well measured as the dynamic trajectory of the approaching craft), based on an irreproducible 'effect' (since the lag, when it is present, goes both ways).

PS And oh, look, it is Yirka again.
Benni
1 / 5 (2) Jan 03, 2014
If Dark Matter, composes 80% of all matter in existence ...


DM is not assumed to be evenly distributed in the universe, otherwise the notion of a DM disc would be nonsense.


I know uneven distribution is the assumption. What has been a mystery is why should it not be evenly distributed, clumpy & lumpy are terms I read for its non-pervasiveness. If one section of a galaxy contains more DM than Visible Matter, then we should see more galaxies that look much less globular or spiral & not lopsided , but mostly we see almost perfect configurations except for cases of collisions where distorting gravitational forces just tear things apart, .

Anything we study about the distribution of energy is that mass randomly spaces itself throughout a system, this entropic process should not be able to pick & choose which mass gets distributed to a specific location inside a galaxy or a specific corner of the Universe. So far that is what we find inside our solar system.
Benni
4 / 5 (1) Jan 03, 2014
Cont'd...........if galaxies had uneven clumpy distribution of DM, we should actually be able to observe any such galaxy as having an odd lopsided appearance. It would only make sense to observe such an appearance because the gravity forces are at a 3:1 ratio in favor of DM. If such a ratio existed inside galaxies they would they not all appear to have a fat end with a very long trailing streamer?
Returners
2.3 / 5 (3) Jan 03, 2014
AP:

You need a highly elliptical satellite orbit, so that the satellite moves in and out of the alleged "Halo" so as to experience more or less of it's alleged gravitational effects. This is so have a basis to compare it to.
yyz
5 / 5 (15) Jan 03, 2014
"DARK MATTER IS HELIUM"

If DM was helium, it would be readily apparent as helium emission lines in optical and x-ray spectra of hot intracluster gas in galaxy clusters. No such helium lines are observed.
Returners
2 / 5 (4) Jan 03, 2014
If there were DM halo around earth, it would no longer be uniform, due to all the space programs. The material would get whipped into a clumpy froth due to the gravitational perturbations caused by the passing spacecraft or satellite.

Also, the Moon's orbital parameters would be wrong, almost certainly by a larger, more readily detectable margin than some mere satellites.

A discrepancy of 0.005 would produce an orbital period discrepancy for the Moon in the realm of minutes, which would have been detected by now rather easily.
Zephir_fan
Jan 03, 2014
This comment has been removed by a moderator.
Returners
2 / 5 (4) Jan 03, 2014
Okay Skippy show me where you are getting the 0.005 from. 0.005 whats? How did you cipher the minutes? And since it is so rather easily, what formula did you use to cipher it?

Skippy you try to hard at this smart guy thing. Take a break, you're making a very uncomplimentary spectacle of yourself.


The 0.005 of 1 percent was from the article, you moron. if you don't know that, you don't deserve a response from me.

How many times do people have to tell you to read the article, before you jump in and start replying to posts?
Zephir_fan
Jan 03, 2014
This comment has been removed by a moderator.
Returners
3 / 5 (4) Jan 03, 2014
Orbital period, assumed Earth mass: 2,372, 594.4885 seconds

Orbital period, 1.00005 of assumed mass: 2,372,535.175869 seconds.

Difference: 59.31 seconds.

Formula:

T = 2pi * sqrt (A^3/GM)

T is time in seconds
G is gravitational constant
M is Earth mass
A is semi-major axis

Seeing as how we have a reflector on the moon, and laser tracker for finding it's exact position and distance, NASA would have to be idiots not to notice a 1 minute error in the Moon's position every month.
Zephir_fan
Jan 03, 2014
This comment has been removed by a moderator.
Returners
3 / 5 (4) Jan 03, 2014
That also equals to about:
2.567cm error per second.

The laser measuring device has a precision higher than this error, and can send out several pulses per second, so if the moon was getting that far ahead of it's expected position, it would be noticed, i.e. the return time would be off, or the pulse would actually miss the reflector, for example.
javjav
4.7 / 5 (3) Jan 04, 2014
The material would get whipped into a clumpy froth due to the gravitational perturbations caused by the passing spacecraft or satellite.

Satellites mass is too small to produce significant gravity, or at least nor enouh to invalidate this theory.

A discrepancy of 0.005 would produce an orbital period discrepancy for the Moon in the realm of minutes, which would have been detected by now rather easily.


I don't think so, because the moon period itself is one of the parameters that was used to estimate the earth mass in our current models, so it will be consistent with or without DM, as the total mass has already been taken into account. If this guy is correct, what would be wrong is our previous model of earth+DM density distribution.

In any case at least you are reasoning with good arguments, what I don't like is those acid critics in other posts. The author doesn't claim that it is proven. It is just an interesting idea that can be tested, and that is good sciene
Returners
3.2 / 5 (5) Jan 04, 2014
I don't think so, because the moon period itself is one of the parameters that was used to estimate the earth mass in our current models, so it will be consistent with or without DM, as the total mass has already been taken into account. If this guy is correct, what would be wrong is our previous model of earth+DM density distribution.


But tests for the gravitational constant have already been done in other ways, such as measuring the weight of something whle indoors vs outdoors, on the top floor of a building vs bottom, etc, and taking into consideration changes in the mass pulling in each direction in such cases. For example, NIST would calculate the mass of the building above the scale, and the gravity of the portion of the building pulling up, and factor that in when trying to determine the gravitational constant.

Since the gravitational constant works for all of the ground tests, it is then a "known" for the moon. continued.
philw1776
5 / 5 (2) Jan 04, 2014
Add Mercury with Messenger almost through its 3rd year around the planet for gravitational anomaly indications. Definitely in the camp that relativity calculations, 3rd body calculations, etc. need be done as Harris states before we have any Earth anomaly. He's likely suggesting to some grad/PhD students that maybe there's a pony hidden under that pile, but likely not.
Benni
1 / 5 (2) Jan 04, 2014
I don't think so, because the moon period itself is one of the parameters that was used to estimate the earth mass in our current models, so it will be consistent with or without DM, as the total mass has already been taken into account. If this guy is correct, what would be wrong is our previous model of earth+DM density distribution.


You make a good point here assuming there is random entropic distribution of DM. But here, Ben Harris is isolating the DM into a ringlike disc from what I can understand, something akin to the rings of Saturn & this is the part that makes no sense.

How would DM figure out how to isolate itself into a ringlike fashion never mixing & evenly distributing itself with visible matter? To perform such a feat DM would need to have anti-gravity qualities, which in the case of a 3:1 ratio of DM to VM there would exist three times more anti-gravity in the universe than normal gravity based upon total mass.
Returners
2.3 / 5 (6) Jan 04, 2014
Now for example, if we "weigh" an object at the equator on the surface, and we get it's "weight," thereby determining G*M at the surface, and then we take the mass of the atmosphere into consideration, this should go into the orbital period equation, and give the results observed in reality.

The fact there has been no obvious divergence reported would mean there is no hidden mass between the top of the atmosphere and the orbit of the Moon.

Why wouldn't a discrepancy that big be noticed? It produces a 2.2km per day error in the moon's position.

Now if you assume they calculate the Earth's mass from the Moon's orbit, they would indeed get the entire hidden DM content if there were any there, HOWEVER, when they do the NIST tests on the ground, they would find an entirely different mass for the Earth, and discover the discrepancy. This hasn't happened, or it would be common knowledge.
Returners
1.8 / 5 (5) Jan 04, 2014
How would DM figure out how to isolate itself into a ringlike fashion never mixing & evenly distributing itself with visible matter? To perform such a feat DM would need to have anti-gravity qualities, which in the case of a 3:1 ratio of DM to VM there would exist three times more anti-gravity in the universe than normal gravity based upon total mass.


I toyed with self-repulsive DM ideas for a while (repels itself, attracts ordinary matter). It seems to work in some contexts, but doesn't work in the greater scheme of things.

There were weird consequences, like needing asymmetry between the attractive and repulsive forces, and it still didn't seem to work at the intergalactic scale regardless. I had to envision sheets and filaments of hidden dark matter greatly exceeding the mass of galaxies, between every galaxy pair. And of course, none of this must interact mechanically with ordinary matter, else it'd destroy us all.
kochevnik
1.7 / 5 (6) Jan 04, 2014
Dark matter is religion, invented to describe a matter deficit because physicists don't account for friction in rotating systems. The Earth cannot rotate any more than an egg. Vortices will cause friction and stop rotation. Physicists don't account for interaction BETWEEN units (atoms etc.) and therefor their calculations of energy are far short
Liquid1474
3.8 / 5 (4) Jan 05, 2014
Applaud those with something to say (Returners, Benni, Anti-alias)...albeit some more creative than others, but I like facilitating a discussion.

However the real 'Skippy' (you know who you are; and everyone else does too) needs to SIT DOWN and let the smart and creative talk...dont worry holmes, its for your own good
Jitterbewegung
1 / 5 (1) Jan 05, 2014
I'd assume that the isolation of the DM into a disk would be caused by slingshots slowing the DM down.
Noumenon
3 / 5 (2) Jan 05, 2014
How accurately can we take the sun and moon into account? I thought our ability to do that is limited by the three-body problem?


While there is no generalized analytic solution, they're not so restricted in using numerical analysis.
pianoman
1 / 5 (1) Jan 05, 2014
A simple question, how does light from galaxies etc, manage to penetrate the several billion light years that it does through DM ?
Noumenon
4.2 / 5 (6) Jan 05, 2014
A simple question, how does light from galaxies etc, manage to penetrate the several billion light years that it does through DM ?


By definition Dark Matter does not absorb nor emit electromagnetic radiation.
Zephir_fan
Jan 05, 2014
This comment has been removed by a moderator.
Benni
5 / 5 (4) Jan 05, 2014
A simple question, how does light from galaxies etc, manage to penetrate the several billion light years that it does through DM ?


By definition Dark Matter does not absorb nor emit electromagnetic radiation.


..........but it will create gravitational lensing, that's what gravitational fields of sufficient strength will do. If there is as much DM out by a 3:1 ratio to VM we should be able to observe gravitational lensing where we probably don't expect to see it.
skippy_skippys
5 / 5 (3) Jan 05, 2014
However the real 'Skippy' (you know who you are; and everyone else does too) needs to SIT DOWN and let the smart and creative talk...dont worry holmes, its for your own good


I suppose you could call thems creative yes. But I also suppose that if you didn't have that computer and miles of copper cables to separate us you would not say that to my face no. So it's the bad karma votes for you Skippy.


Is the ira not smart enough to see the hypocrisy in taking offense to Liquid1474 post?
Zephir_fan
Jan 05, 2014
This comment has been removed by a moderator.
skippy_skippys
4.7 / 5 (3) Jan 05, 2014
However the real 'Skippy' (you know who you are; and everyone else does too) needs to SIT DOWN and let the smart and creative talk...dont worry holmes, its for your own good


I suppose you could call thems creative yes. But I also suppose that if you didn't have that computer and miles of copper cables to separate us you would not say that to my face no. So it's the bad karma votes for you Skippy.


Is the ira not smart enough to see the hypocrisy in taking offense to Liquid1474 post?


No not really. I wouldn't call him a hypocrite, more like a copying cat.


Is the ira too stupid to understand the skippy_skippys was saying that the ira is the hypocrite?

But even was he trying to be the hypocrite, he was still being stupid and I really doubt he would be so stupid if he was face to face with the Ira no.


Is that a threat from the ira? Is that better or worse than being stupid ira?
IMP-9
5 / 5 (6) Jan 05, 2014
Mainstream science has NO PLAN for what it will do in the event that dark matter does not exist...


Only if you completely ignore alternative theory. the fact that there are few strong alternatives is not criticism of a theory.

Physicists should actually be alarmed that there is no existing system for innovating new, divergent ideas in their discipline. All new ideas get shot down due to a failure in "accuracy".


It's a real shame that people expect astrophysical theory to reflect observation isn't it? No, this is what separates hypothesis from theory. Models don't get shot down unless the theory stagnates, many theories like MoND have been around for decades. Dark matter is still the stronger model.
HannesAlfven
1 / 5 (5) Jan 05, 2014
Re: "It's a real shame that people expect astrophysical theory to reflect observation isn't it?"

You have no clue how innovation occurs. Talk to any person that actually creates anything in the world. They will explain it to you. There are two halves to the cycle: The first half is based upon divergence from the status quo, while the other is a form of convergence. The set of values for these two halves is very different: In order to come up with good ideas, a person has to first be willing to diverge sufficient for an idea to get off the ground. In science, the proper way to diverge is at the level of concepts and propositions. A good designer will spend most of his time carefully mapping out the problem space in terms of what is conceptually possible.

The process of convergence is where you check for accuracy (problem-solving). Modern theorists spend all of their time converging, and far too little time diverging. They view divergence as "inaccurate".

[…]
Captain Stumpy
5 / 5 (5) Jan 05, 2014
Kochevnik claims
Dark matter is religion

dark matter is just a name, and a temporary one at that.
A "place holder" that is a heck of a lot shorter than saying "that weird crap that we can see the effects of and measure the gravitational effects of but cannot see or interact with"

but i am sure you knew that.

Only if you completely ignore alternative theory. the fact that there are few strong alternatives is not criticism of a theory.


THANK YOU
i guess the poster of
Mainstream science has NO PLAN for what it will do in the event that dark matter does not exist

does not understand science much
They view divergence as "inaccurate"

only when it cant be proven with empirical data, experimentation (that can be replicated) etc

you do the divergence and make something that sticks, then it DOES
for example: Einstein
HannesAlfven
2.1 / 5 (7) Jan 05, 2014
The end result is that most ideas that conventional thinkers come up with are computationally accurate, but conceptually questionable. You can see the mistake in the nature of these physorg comments: The people who are truly engaging the subject go straight into calculation. There is rarely any discussion of the underlying concepts and propositions.

If you look closely at physics education research, it's become clear that most people have failed to assimilate the principles of Newtonian mechanics. Many, if not most, students come OUT of college physics classes as Aristotelian thinkers. We know this is true by administering force concept inventory tests to them. The data we've had for a couple of decades now is that the problem is far worse than most people realize. Many students have learned that they can do quite well in school by simply memorizing the problem-solving recipes, but we question models through concepts too. So, many lack an ability to question their knowledge.
HannesAlfven
1.7 / 5 (6) Jan 05, 2014
From the YouTube video "Confessions of a Converted Lecturer" …

"It's very important to have data in education. I often go to faculty meetings where my colleagues and I talk about teaching, and there are quite a few Nobel laureates around me. It is always surprising to me how whenever the discussion shifts from physics to education, people - even the most reputable scientist - completely abandon the scientific method. All of a sudden, the discussion is about anecdotes … My students learn better when blah blah blah … Or, my students like it when I do this, as if liking equates better learning."

[…]

"So, I would argue that there's much more that needs to happen than just delivering information. And the fact that delivering information was not enough became clear when I gave this FCI. What is it that needs to happen? … What needs to happen is that the student needs to make sense of the information, build mental models …"
HannesAlfven
1.7 / 5 (6) Jan 05, 2014
"… that you can use in other contexts. I would call that assimilating the information."

[…]

[Mazur routinely gives his students tests which have both traditional problem sets and conceptual comprehension questions (FCI's). Look at what he observes …]

"The student who does well on the conceptual problem tends to do well on the conventional problem, so if you understand the basics, you're gonna do well on the conventional problem. However, there's 40% that does well on the conventional problem, but has no clue on the basics. What are these 40%? When I saw this diagram, everything fell into place. How would you characterize these 40%? How do they get there? Who are these students? What are they doing? Memorizing … Plug and chug, right?"
HannesAlfven
1 / 5 (5) Jan 05, 2014
The universities actually encourage rote memorization of problem set recipes. This was part of the critique of the physics PhD program which we saw made by Jeff Schmidt in his book, Disciplined Minds: That physics graduate students are oftentimes told to memorize an enormous stack of problem sets. Schmidt argues that the point is to distinguish those students who stop to think about what they're memorizing from the more gung-ho types. The reason they do this is because industry needs disciplined thinkers who will not question the project parameters. This keeps projects running smoothly.

Now, the problem for conventional science is that the needs of industry very obviously conflict with the needs of society. Society needs thinkers who WILL question the assumptions inherent to our models. That is part of thinking like a scientist, and there is no point to engaging a subject like dark matter when you've already been trained to avoid questioning assumptions.
Captain Stumpy
5 / 5 (5) Jan 05, 2014
@HannesAlfven
I really wont argue with most of that... all except the last part. After
The reason they do this

I keep coming back to:
IF you have the hypothesis
AND it makes sense
AND you can prove it mathematically as well as experimentally
AND the experiments are reproducible (etc, etc)
THEN you have PROOF and there isn't much the scientists can do at that point except argue semantics...
this is how the science works, and I tend to believe it.
We have too many demonstrations of "far fetched" ideas that are completely successful.
(think QM)

Admittedly, I must qualify that with "in the past"... but I hold out hope that this is still true today.

the reason i dont go STRAIGHT to calculations is:
1st
do i understand WHAT the person is asking?
2nd
the math comes AFTER the understanding- establish parameters for good communication FIRST.

once you understand each other, then go for proof
HannesAlfven
1.7 / 5 (6) Jan 05, 2014
Re: "THEN you have PROOF"

But, notice that in order to ask GOOD questions, there is a very different set of values involved than what is necessary to build accurate models. Mainstream scientists do not observe these two competing sets of values. They take the set of values associated with building accurate models and erroneously apply it to this process of asking questions.

This is apparent from the effort they go through at the inferential step. The inferential step is that point where, in theory, all of the worldviews of science are given some thought as possible explanations. Notice that conventional thinkers generally do not put any effort into actually becoming fluent in all of these competing worldviews. They interpret the Sagan Standard as a reason to wait for good ideas to reveal themselves; they do not actively seek out these ideas. So, what happens is that when it comes time to infer, conventional thinkers only have their own personal worldviews to draw ideas from.
HannesAlfven
1 / 5 (4) Jan 05, 2014
The fact is that the way in which we train physicists today is geared towards generating new technologies, to the detriment of answering the big questions in science. Those two very different endeavors involve very different mindset and values to service them. We will never answer the biggest questions in science in this manner.

If people really want to answer these big questions in cosmology, we have to re-engineer the way in which we train physicists. There are good ideas already out there in the fringes of scientific investigation, but the problem is that nobody has brought any order to that chaos. It takes more than a lifetime to sort through just a single wicked problem. People see the complexity of the problem of sorting through all of these questionable models, and the rational mind just SHUTS DOWN.

If people want to answer these big questions, the first step is to bring order to the fringes of scientific investigation.
Mike_Massen
5 / 5 (3) Jan 05, 2014
indio007 Muttered oblivious to variety of corrections with this potentially embarrassing gem forever connected to the level of his thinking process
GPS does not verify relativity.
RON HATCH: Relativity in the Light of GPS
http://www.youtub...1GU_HDwY
Might I suggest you get up to speed with foundations of relatively by starting here, simple I know but one must start somewhere:-

http://en.wikiped...periment

AND

http://en.wikiped...g_System

& offer references other than a random talk, how about a peer reviewed journal or your own maths please, that would be nice, I love maths with breakfast - scrambled eggs with Earl Grey tea & masses of Chilli lada padi on the eggs - yum, followed by nicely crafted differential equations - with a subset of contemporary philosophy on the subject/object conjecture & the mind body problem - for which I have a solution btw: which I use as a tool :-)

baudrunner
2.8 / 5 (4) Jan 05, 2014
If DM was helium, it would be readily apparent as helium emission lines in optical and x-ray spectra of hot intracluster gas in galaxy clusters. No such helium lines are observed.
I have to assume that you are just pulling this off the top of your head, or no real study has been made to find Helium in space. Helium is the second most abundant element in the Universe, yyz. It is rare on Earth, and not replenishable, nor is it manufacturable, unless you want to split hairs and start talking about Hydrogen fusion reactions. The Lunar Reconnaissance Orbiter detected Helium on the Moon: "Because helium also resides in the interplanetary background, several techniques were applied to remove signal contributions from the background helium and determine the amount of helium native to the moon. Geophysical Research Letters published this research in 2012." The sun is comprised of 24% Helium by mass. Furthermore, it was discovered in space 26 years before it was found on Earth.
baudrunner
1 / 5 (5) Jan 05, 2014
And from 'The Universe Today': "If you look at space the majority of Helium is in stars and the interstellar medium." Of course Dark Matter is Helium.

Returners
2.3 / 5 (3) Jan 05, 2014
One of the fallacies surrounding Dark Matter is the assumption that Dark Matter is actually "Matter" at all.

It is quite different to say, "It appears objects in the spiral galaxy are moving faster than they should be according to known attractive forces," as compared to, "Objects in the spiral galaxy are moving faster than they should because there is a hidden, invisible, chargeless, non-interacting form of matter which always appears in exactly the right place to explain the discrepancies in observations."

One of those statements corresponds to an observation.

The other statement is a conjecture which is non-falsifiable, unless another theory is proven absolutely true.

That is to say, the only way to disprove DM theory (since we can't prove it either,) is to prove absolutely that something else does the "apparent force" discrepancy instead.
Benni
5 / 5 (1) Jan 05, 2014
One of the fallacies surrounding Dark Matter is the assumption that Dark Matter is actually "Matter" at all.


Then how would you explain why many gravitational lenses exhibit a much greater angle of bending than their inherent luminosity would predict? This is gravity acting on visible electro-magnetism as it passes through the vicinity of massive bodies. What non-matter do you know of that has gravity, we could start there.

..... the only way to disprove DM theory (since we can't prove it either,) is to prove absolutely that something else does the "apparent force" discrepancy instead.


OK, your on.........What? What is it that has gravity which causes the excess bending observed in so many gravitational lenses? Many of these lenses are so severely distorted by gravity that the actual ratio of visible matter to the unknown gravity source seems to be about 5:1 or 6:1, some say higher. That's an awfully lot of unaccounted for gravity to create such lens distortions.
kochevnik
1 / 5 (4) Jan 05, 2014
One of the fallacies surrounding Dark Matter is the assumption that Dark Matter is actually "Matter" at all.


Then how would you explain why many gravitational lenses exhibit a much greater angle of bending than their inherent luminosity would predict? This is gravity acting on visible electro-magnetism as it passes through the vicinity of massive bodies. What non-matter do you know of that has gravity, we could start there.
This is due to the tetrahedral structure of timespace. If you examine the large scale order of galaxies you will see they are stacked in tetrahedrons. The inflow and outflow of timespace causes the distortions of the fictitious "dark matter", as their centeres contain naked singularities
Benni
4.5 / 5 (2) Jan 05, 2014
"This is due to the tetrahedral structure of timespace."

This is the source of the gravity? What if the timespace structure were hexahedrons & mass doesn't change?

MRBlizzard
not rated yet Jan 05, 2014
Here's the presentation:
Poster session at AGU

http://fallmeetin...rg/2013/ select "eposters" search for Author "Harris"
kochevnik
1 / 5 (2) Jan 05, 2014
"This is due to the tetrahedral structure of timespace."

This is the source of the gravity? What if the timespace structure were hexahedrons & mass doesn't change?

Not the gravity of "dark matter". What they claim is gravitational bending is actually the tetrahedral structure of matter at all timescales. The same fallacy caused physicists to postulate a strong and weak nuclear force, which are simply gravity becoming extremely powerful near the naked singularity at the center of atoms

Structure is the most fundamental of all things. The structure of the vacuum creates particles out of nothing even in the absence of energy
TheGhostofOtto1923
4.2 / 5 (5) Jan 05, 2014
A while ago, a colleague mentioned to me that JPL's General Relativistic model for our Solar System contained a best fit background, gravitational field. I don't see why this couldn't be the result of a light year scale, dark matter stream near our solar system. By stream, I am alluding to streams of stars in the Milky Way arising from smaller galaxies being taken in by the Milky Way. Yes, the Earth is much, much smaller; however, the mass of the Earth is unknown. What we work with is GxM (gravitational constant times mass of the Earth). That stays pretty constant, but we don't know the value of G. So the estimate of the Earth's mass changes by values larger than 10^17 metric tons.

2. Where can I get the whole paper?
Why don't you try google?
Rute
3 / 5 (1) Jan 06, 2014
If the hypothesized dark matter disk would be located as a disk above the equator, then surely it would have a measurable impact on the differences of gravitational pull between the surface environments of the polar regions and equatorial regions of Earth. To my understanding there exists a difference but it is completely explained by the difference in centrifugal force of those regions due to Earth's rotation around its own axis. EDIT: The equatorial bulge has an effect as well and it is supposed to contribute half to the observed difference.

From Wikipedia: "In combination, the equatorial bulge and the effects of the Earth's inertia mean that sea-level gravitational acceleration increases from about 9.780 m·s−2 at the Equator to about 9.832 m·s−2 at the poles, so an object will weigh about 0.5% more at the poles than at the Equator.[5][6]"
Benni
5 / 5 (1) Jan 06, 2014
"This is due to the tetrahedral structure of timespace."


This is the source of the gravity? What if the timespace structure were hexahedrons & mass doesn't change?

Not the gravity of "dark matter". What they claim is gravitational bending is actually the tetrahedral structure of matter at all timescales.The same fallacy caused physicists to postulate a strong and weak nuclear force, which are simply gravity becoming extremely powerful near the naked singularity at the center of atoms


?

Structure is the most fundamental of all things. The structure of the vacuum creates particles out of nothing even in the absence of energy


.......not if you believe in the laws of Conservation of Energy. You just did a good job of proposing "perpetual motion". I don't know how particles can be created "out of nothing" without an input of energy such as occurs in photosynthesis.
Captain Stumpy
5 / 5 (1) Jan 06, 2014
ok...IF
In general relativity, a naked singularity is a gravitational singularity without an event horizon.

and
In a black hole, the singularity is completely enclosed by a boundary known as the event horizon, inside which the gravitational force of the singularity is strong enough so that light cannot escape. Hence, objects inside the event horizon—including the singularity itself—cannot be directly observed. A naked singularity, by contrast, is observable from the outside.

THEN
even at small scales, the singularity would begin to pull ALL matter INTO it and crush it/absorb it growing as it does,
AND
being small and hot it would then also EVAPORATE incredibly quickly

therefore a "naked singularity" CANNOT possibly EXIST
INSIDE
an object like protons and neutrons where the Strong and weak nuclear forces are at work

...to be continued
Captain Stumpy
5 / 5 (2) Jan 06, 2014
...cont
therefore
The same fallacy caused physicists to postulate a strong and weak nuclear force, which are simply gravity becoming extremely powerful near the naked singularity at the center of atoms

can be determined to be total nonsense or pseudo-science
WITHOUT even having to do ANY math

there would ALSO be signs of Hawking radiation
(of which I have heard NOTHING about as of yet, even as well studied the atom tends to be)

now as for
The structure of the vacuum creates particles out of nothing even in the absence of energy


it is creating "Virtual" particles and they do not exist for long enough to even measure, but give off energy of which we are able to measure

you must be plugging for one of the PU/EU hypothesis... or is it another?
Captain Stumpy
5 / 5 (2) Jan 07, 2014
Sorry,
my last TWO posts are directed at
kochevnik

who stated
The same fallacy caused physicists to postulate a strong and weak nuclear force, which are simply gravity becoming extremely powerful near the naked singularity at the center of atoms


when there obviously CANNOT be a singularity inside a proton/neutron (or at the center of atoms) "causing" the strong/weak nuclear forces
A singularity means a point where some property is infinite. For example, at the center of a black hole, according to classical theory, the density is infinite (because a finite mass is compressed to a zero volume).

http://curious.as...umber=55
Mike_Massen
not rated yet Jan 07, 2014
I concur with those that show there cannot be a singularity in accepted physics sense, it occurs to me to look at singularity in the probabilistic sense.

Have been thinking on this for decades since exploring advanced probability & stats in a post grad unit at Western Australian Institute of Technology in 1981, I never bothered completing it as it didnt seem to have hard practical aspect but, for some 10 years or it seems there is a hard issue to address.

ie.Space is replete with energy, one aspect is virtual particles. The casimir effect seems to show that when excluding some of the probabilities of wave phenomena a force is generated.

One might then infer particles are none other than a device by which the largely infinite probabilities of space are reduced to a finite subset and this coalescence, if you like, gives rise to what we classify as a particle. Different exclusions give rise to different particles.

The more probabilities that are excluded the more mass is observed.
eHofmann
not rated yet Jan 10, 2014
... there is more that bothers me concerning "dark matter" ... how can we name "something" that, clearly, can't be seen "dark matter" and not "invisible matter" ... darkness is the absence of light and can be "seen" indirectly ... invisibility is just what it say and what this matter actually is, so it seems. Can anyone please explain why we/they don't just call this "invisible matter" ...

Erwin

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