Researchers interpret new experimental data aimed at showing dark matter interacts with ordinary matter

July 13, 2018, University of California - Riverside
In search of dark matter
Photo shows PandaX, a xenon-based detector in China. Credit: PandaX.

An international team of scientists that includes University of California, Riverside, physicist Hai-Bo Yu has imposed conditions on how dark matter may interact with ordinary matter—constraints that can help identify the elusive dark matter particle and detect it on Earth.

Dark —nonluminous material in space—is understood to constitute 85 percent of the matter in the universe. Unlike normal matter, it does not absorb, reflect, or emit light, making it difficult to detect.

Physicists are certain dark matter exists, having inferred this existence from the gravitational effect dark matter has on visible matter. What they are less certain of is how dark matter interacts with ordinary matter—or even if it does.

In the search for direct detection of dark matter, the experimental focus has been on WIMPs, or weakly interacting massive , the hypothetical particles thought to make up dark matter.

But Yu's international research team invokes a different theory to challenge the WIMP paradigm: the self-interacting dark matter model, or SIDM, a well-motivated framework that can explain the full range of diversity observed in the galactic rotation curves. First proposed in 2000 by a pair of eminent astrophysicists, SIDM has regained popularity in both the particle physics and the astrophysics communities since around 2009, aided, in part, by work Yu and his collaborators did.

Yu, a theorist in the Department of Physics and Astronomy at UCR, and Yong Yang, an experimentalist at Shanghai Jiaotong University in China, co-led the team analyzing and interpreting the latest data collected in 2016 and 2017 at PandaX-II, a xenon-based dark matter direct detection experiment in China (PandaX refers to Particle and Astrophysical Xenon Detector; PandaX-II refers to the experiment). Should a dark matter particle collide with PandaX-II's liquefied xenon, the result would be two simultaneous signals: one of photons and the other of electrons.

Yu explained that PandaX-II assumes dark matter "talks to" normal matter—that is, interacts with protons and neutrons—by means other than gravitational interaction (just gravitational interaction is not enough). The researchers then search for a signal that identifies this interaction. In addition, the PandaX-II collaboration assumes the "mediator particle," mediating interactions between dark matter and normal matter, has far less mass than the mediator particle in the WIMP paradigm.

"The WIMP paradigm assumes this mediator particle is very heavy—100 to 1000 times the mass of a proton—or about the mass of the dark matter particle," Yu said. "This paradigm has dominated the field for more than 30 years. In astrophysical observations, we don't, however, see all its predictions. The SIDM model, on the other hand, assumes the mediator particle is about 0.001 times the mass of the dark matter particle, inferred from astrophysical observations from dwarf galaxies to galaxy clusters. The presence of such a light mediator could lead to smoking-gun signatures of SIDM in dark matter direct detection, as we suggested in an earlier theory paper. Now, we believe PandaX-II, one of the world's most sensitive direct detection experiments, is poised to validate the SIDM model when a dark matter particle is detected."

The international team of researchers reports July 12 in Physical Review Letters the strongest limit on the interaction strength between dark matter and visible matter with a light mediator. The journal has selected the research paper as a highlight, a significant honor.

"This is a particle physics constraint on a theory that has been used to understand astrophysical properties of dark matter," said Flip Tanedo, a dark matter expert at UCR, who was not involved in the research. "The study highlights the complementary ways in which very different experiments are needed to search for dark matter. It also shows why theoretical physics plays a critical role to translate between these different kinds of searches. The study by Hai-Bo Yu and his colleagues interprets new experimental data in terms of a framework that makes it easy to connect to other types of experiments, especially astrophysical observations, and a much broader range of theories."

PandaX-II is located at the China Jinping Underground Laboratory, Sichuan Province, where pandas are abundant. The laboratory is the deepest underground laboratory in the world. PandaX-II had generated the largest dataset for when the analysis was performed. One of only three xenon-based dark matter direct detection experiments in the world, PandaX-II is one of the frontier facilities to search for extremely rare events where scientists hope to observe a dark matter particle interacting with ordinary matter and thus better understand the fundamental particle properties of dark matter.

Particle physicists' attempts to understand dark matter have yet to yield definitive evidence for dark matter in the lab.

"The discovery of a interacting with ordinary matter is one of the holy grails of modern physics and represents the best hope to understand the fundamental, particle properties of dark matter," Tanedo said.

For the past decade, Yu, a world expert on SIDM, has led an effort to bridge particle physics and cosmology by looking for ways to understand dark matter's particle properties from astrophysical data. He and his collaborators have discovered a class of dark matter theories with a new dark force that may explain unexpected features seen in the systems across a wide range, from dwarf galaxies to galaxy clusters. More importantly, this new SIDM framework serves as a crutch for particle physicists to convert astronomical data into particle physics parameters of . In this way, the SIDM framework is a translator for two different scientific communities to understand each other's results.

Now with the PandaX-II experimental collaboration, Yu has shown how self-interacting dark matter theories may be distinguished at the PandaX-II experiment.

"Prior to this line of work, these types of laboratory-based dark matter experiments primarily focused on dark matter candidates that did not have self-interactions," Tanedo said. "This work has shown how dark forces affect the laboratory signals of dark matter."

Yu noted that this is the first direct detection result for SIDM reported by an experimental collaboration.

"With more data, we will continue to probe the dark matter interactions with a light mediator and the self-interacting nature of ," he said.

Explore further: 3 knowns and 3 unknowns about dark matter

More information: Xiangxiang Ren et al. Constraining Dark Matter Models with a Light Mediator at the PandaX-II Experiment, Physical Review Letters (2018). DOI: 10.1103/PhysRevLett.121.021304

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tallenglish
1.6 / 5 (8) Jul 13, 2018
I think this too will show a null result. DM is connected via spacial dimensions only and inverse of time. So DM is to negative time as mass is to positive time and both curve spacetime in mutually opposite ways.

Explains why they only interact via gravity, what the source of the big bang was and why it tends to be where mass isnt (like around galaxies).

You have to assume time is inherintly cyclical though so +/- infinity is where it reflects back on itself and t=0 where there is greatest interaction between the two.

Question is DM also the missing anti-matter from the big bang as well?
Old_C_Code
2.2 / 5 (13) Jul 13, 2018
DM is a math error. I can't believe people buy this crap, seems like no evidence required what so ever, just a fudge factor in an equation.
RealityCheck
3.2 / 5 (11) Jul 13, 2018
From the second-last paragraph in above article:
Yu noted that this is the first direct detection result for SIDM reported by an experimental collaboration.


When just before that, in the fourth-last paragraph:
Now with the PandaX-II experimental collaboration, Yu has shown how self-interacting dark matter theories MAY be distinguished at the PandaX-II experiment.
So there has been NO actual "direct detection result for SIDM" at all!

So far its ONLY their HYPOTHESIS/HOPE that a future 'DM detection event' MAY 'occur'; and that it MAY 'confirm' their hypothesis/hope!

'Publish-or-Perish' imperative strikes again. :)
arcmetal
2.2 / 5 (10) Jul 13, 2018
DM is a math error. I can't believe people buy this crap, seems like no evidence required what so ever, just a fudge factor in an equation.

Pursuits of money distorts so much. Grifters will be grifters.

A cardboard box surrounded by duct tape would get the same results.
gculpex
2.6 / 5 (5) Jul 13, 2018
Thank you, RealityCheck
jonesdave
3 / 5 (14) Jul 13, 2018
Oh dear. Spot the non-scientifically qualified above! Science really isn't their thing, is it? Bless them. Guess that when you are crap at a particular subject at school, and you get the p!ss taken out of you because of it, you end up believing woo, and have an enormous chip on your shoulder. W*nk*rs.
Give it up, lads, you're fooling nobody with your ignorance.
eachus
3 / 5 (4) Jul 13, 2018
Sorry. I happen to think that DM interacts with matter through the weak force, and since the weak force is mediated by the (heavy) W+, W−, and Z bosons, the only long distance interaction we see with DM is via gravity. However there are huge numbers of neutrinos that can interact via the weak force, and a large fraction of them in the vicinity of Earth are headed away from the sun. Could this be what is sweeping DM from the solar system? Something must be--or you can believe that all the DM in the solar system is in the core of the sun and various planets. A lot of gravity experiments, both intentional and accidental put the mass of free DM in the solar system at zero. (Accidental experiments are things like the Pioneer Anomaly.--which was resolved.) In fact, I think we can rule out significant DM in the sun.

Is it possible that there are a few hundred DM particles passing through the solar system per year? I guess so, but don't expect one of them to hit a detector soon.
Benni
3.8 / 5 (10) Jul 13, 2018
Oh dear. Spot the non-scientifically qualified


So why are you here? All you ever do is spend your time on name calling rants.
RealityCheck
3 / 5 (10) Jul 13, 2018
@jonesdave.
Oh dear. Spot the non-scientifically qualified above! Science really isn't their thing, is it? Bless them. Guess that when you are crap at a particular subject at school, and you get the p!ss taken out of you because of it, you end up believing woo, and have an enormous chip on your shoulder. W*nk*rs.
Give it up, lads, you're fooling nobody with your ignorance.
Why do you (an otherwise intelligent person) keep making such drive-by trolling insult posts adding nothing of value to thread/discourse, jonesy? It only confirms your agenda here is NOT science discourse/understanding, but trolling and ego/denial crap. So stop your own "W*nk*ing". Go read article (and my post) in thread:

https://phys.org/...rce.html

Then admit I was correct all along in...

https://phys.org/...ary.html

I try to get you/RNP 'up to speed' (by 'connecting the dots' for you), but you just deny/insult.

Learn. :)
howhot3
5 / 5 (1) Jul 14, 2018
Sorry. I happen to think that DM interacts with matter through the weak force, and since the weak force is mediated by the (heavy) W+, W−, and Z bosons, the only long distance interaction we see with DM is via gravity. However there are huge numbers of neutrinos that can interact via the weak force, and a large fraction of them in the vicinity of Earth are headed away from the sun. Could this be what is sweeping DM from the solar system? Something must be--or you can believe that all the DM in the solar system is in the core of the sun and various planets. A lot of gravity experiments, both intentional and accidental put the mass of free DM in the solar system at zero. (Accidental experiments are things like the Pioneer Anomaly.--which was resolved.) In fact, I think we can rule out significant DM in the sun.

Excellent post! But what if DM is just a small modification to GR? Would it not appear the same as DM?
Parsec
5 / 5 (8) Jul 14, 2018
@hotshot3 - The decades old controversy of DM vs MTOG has basically been laid to rest. If a modified theory of gravity was able to explain the radial rotational speed abnormalities, then we should see that modification for all galaxies. But we do not. There are a few galaxies inside large clusters that have been seemingly swept free of DM because they have normal Einsteinian gravity velocity curves. In other words, MOTG continues to have more and more evidence stacked up against it.

The velocity curves I am talking about is a map of the radial velocity of stars as plotted from distance from the center of a galaxy.
Ojorf
4.2 / 5 (5) Jul 14, 2018
DM might be a WIMP!
There is still place wheres they could be hiding:

"Plot showing the parameter space of dark matter particle mass and interaction cross section with nucleons. The LUX and SuperCDMS limits exclude the parameter space above the labelled curves. The CoGeNT and CRESST-II regions indicate regions which were previously thought to correspond to dark matter signals, but which were later explained with mundane sources. The DAMA and CDMS-Si data remain unexplained, and these regions indicate the preferred parameter space if these anomalies are due to dark matter."
https://upload.wi...ints.png

Not to say it IS a WIMP, DM might mot interact via the weak force, don't know yet.
Modified gravity is pretty much ruled out though.
tomwestboro
1 / 5 (6) Jul 14, 2018
Dark matter is a supersolid that fills empty space and is displaced by the protons and neutrons the Earth consists of. What is referred to geometrically as curved spacetime physically exists in nature as the state of displacement of the supersolid dark matter. The state of displacement of the supersolid dark matter is gravity.
TheGhostofOtto1923
4 / 5 (4) Jul 14, 2018
Dark matter is a supersolid that fills empty space and is displaced by the protons and neutrons the Earth consists of. What is referred to geometrically as curved spacetime physically exists in nature as the state of displacement of the supersolid dark matter. The state of displacement of the supersolid dark matter is gravity
No it's not.
Old_C_Code
1.8 / 5 (5) Jul 14, 2018
Dark matter is a math error. These comments are insane.
howhot3
5 / 5 (2) Jul 14, 2018
Good objection @parsec, I didn't think about the rotational speed anomaly of GR. Instead, I was thinking about the Emergent Gravity concept of an additional entropic force when a paritition of space is occupied by matter. The entropic forces are developed in Hawkin's work on the event horizon I believe. Just google Entropic Gravity. It seems like a better solution to DM than all of the made up particle concepts where the particles have to have magic properties to fit observations.
Cusco
5 / 5 (4) Jul 14, 2018
Dark matter is a math error. These comments are insane.


So physicists worldwide have been making the same error over and over for almost a century? Care to explain how that works?
Old_C_Code
1.7 / 5 (6) Jul 14, 2018
Dark matter is a math error. These comments are insane.

So physicists worldwide have been making the same error over and over for almost a century? Care to explain how that works?

Almost a century? lol, You never heard about dark matter till recently trying to explain why the rotation equation doesn't work. It tries to take into account a galaxy that won't spin right. No mass, no charge, no f***ing evidence what so ever. Dopes.

TheGhostofOtto1923
4 / 5 (4) Jul 15, 2018
Dark matter is a math error
No it's not.
These comments are insane
No they're not.
Dopes
No you're a dope.
Reg Mundy
not rated yet Jul 15, 2018
@jonesdave.
Oh dear. Spot the non-scientifically qualified above! Science really isn't their thing, is it? Bless them. Guess that when you are crap at a particular subject at school, and you get the p!ss taken out of you because of it, you end up believing woo, and have an enormous chip on your shoulder. W*nk*rs.
Give it up, lads, you're fooling nobody with your ignorance.
Why do you (an otherwise intelligent person) keep making such drive-by trolling insult posts adding nothing of value to thread/discourse, jonesy? It only confirms your agenda here is NOT science discourse/understanding, but trolling and ego/denial crap. So stop your own "W*nk*ing". Go read article (and my post) in thread:

https://phys.org/...rce.html

I try to get you/RNP 'up to speed' (by 'connecting the dots' for you), but you just deny/insult.

Learn. :)

C'mon, RC, put the tw*t on your ignore list like I advised Benni to do....
Reg Mundy
3.2 / 5 (5) Jul 15, 2018
Why don't you forget DM and simply apply expansion theory to known masses? It produces excellent agreement with observation. but it is obviously not as lucrative as inventing DM and DE and creating experiments to search for them....
Cusco
4.2 / 5 (6) Jul 15, 2018
[qYou never heard about dark matter till recently trying to explain why the rotation equation doesn't work.

Fritz Zwicky detected dark matter in the Coma Cluster of galaxies in 1933, 15 years short of a century (thus "almost"). There is more mass in the universe than we can detect with our current equipment at scales less than a galaxy, that's an observable fact for galaxies, galactic clusters, superclusters and clusters of superclusters.
jonesdave
2.7 / 5 (7) Jul 15, 2018
Why don't you forget DM and simply apply expansion theory to known masses? It produces excellent agreement with observation. but it is obviously not as lucrative as inventing DM and DE and creating experiments to search for them....


Hey, Reg? Stop being such a dickhead. Yes? Write the paper, woo boy. A Nobel awaits you, sh1t f0r brains. Yes? What is stopping you, woo boy? Bit dumb, aren't we Reggie boy? Science wasn't your first choice at school (assuming you ever attended one) was it, dear? Got a bit of a chip on your shoulder about that, haven't we Reg?
Come on Reg, own up! You are the idiot Thornhill! Correct? Nobody could be that stupid, and keep pumping out the same shite, without either being the idiot in question, or being very close to the idiot in question. Correct, Reg?
Science is not really your thing, is it dear? Lay off it Reg! Whatever you're smoking, just stop it. Yes?
Benni
2.2 / 5 (10) Jul 15, 2018
There is more mass in the universe than we can detect with our current equipment at scales less than a galaxy, that's an observable fact for galaxies, galactic clusters, superclusters and clusters of superclusters.


Then why can't we find any of it within our solar system? I know, it's the magic of distance that creates it's obscurity within our solar system, right? Our solar system is just not near enough to a big pocket of this Pop-Cosmology fantasy to make it detectable, right?
jonesdave
3.8 / 5 (10) Jul 15, 2018
There is more mass in the universe than we can detect with our current equipment at scales less than a galaxy, that's an observable fact for galaxies, galactic clusters, superclusters and clusters of superclusters.


Then why can't we find any of it within our solar system? I know, it's the magic of distance that creates it's obscurity within our solar system, right? Our solar system is just not near enough to a big pocket of this Pop-Cosmology fantasy to make it detectable, right?


Benni? Give up dear. Yes? This stuff is waaaay beyond you. Correct?
Benni
2.8 / 5 (9) Jul 15, 2018
Hey, Reg? Stop being such a dickhead. Yes? Write the paper, woo boy. A Nobel awaits you, sh1t f0r brains. Yes? What is stopping you, woo boy? Bit dumb, aren't we Reggie boy? Science wasn't your first choice at school (assuming you ever attended one) was it, dear? Got a bit of a chip on your shoulder about that, haven't we Reg?
Come on Reg, own up! You are the idiot Thornhill! Correct? Nobody could be that stupid, and keep pumping out the same shite, without either being the idiot in question, or being very close to the idiot in question. Correct, Reg?
Science is not really your thing, is it dear? Lay off it Reg! Whatever you're smoking, just stop it. Yes?


......and you have nothing better to do with your time? Your ONLY "thing" is your foul mouthed ranting, you should try something else as a retirement career.
jonesdave
3.3 / 5 (7) Jul 15, 2018
@Benji,
Hey, sh1t f0r brains! How you doing, woo boy? Science is still a bit beyond you, isn't it dear? Go away, Benji. Sweep some floors, or whatever else you do, dear. Stay away from science, luv, because you are a bit crap at it. Correct?
Has that nuclear power station that you live near got a restraining order on you yet? If not, they seriously need to get one sorted out. Couldn't give a crap, personally, as I'm not in that continent. However, other people are.....
RealityCheck
2.1 / 5 (7) Jul 15, 2018
@Reg Mundy.
@jonesdave. Why do you (an otherwise intelligent person) keep making such drive-by trolling insult posts adding nothing of value to thread/discourse, jonesy? It only confirms your agenda here is NOT science discourse/understanding, but trolling and ego/denial crap. So stop your own "W*nk*ing". Go read article (and my post) in thread:

https://phys.org/...rce.html

I try to get you/RNP 'up to speed' (by 'connecting the dots' for you), but you just deny/insult.

Learn. :)
C'mon, RC, put the tw*t on your ignore list like I advised Benni to do..
My username also reflects my function here; namely: to provide indicated reality checks when comments/assertions are made which are egregiously at odds with the objective logic and/or science relating to the reality. It's a sacrifice worth the making in the interests of science, RM. And one can hardly do reality checks if one puts others on 'ignore', can one? :)
RealityCheck
2.6 / 5 (5) Jul 15, 2018
PS @Reg Mundy.

I also noted your following post/comment (presumably 'addressed' to forum at large?):
...forget DM and simply apply expansion theory to known masses? It produces excellent agreement with observation. but it is obviously not as lucrative as inventing DM and DE and creating experiments to search for them..
I must agree, it is not as 'lucrative' as that 'publish-or-perish' studies/papers 'industry' that has been 'going strong to nowhere' for DECADES now, due mainly to 'exotic' DM/DE/INFLATION/BigBang-caused furphies.

PPS: Your post reminded me that, in our last conversation way back when, I may have omitted to ask you how your expansion theory treats ROTATION and the various variables/consequences if a point on the surface of a spherical body (eg, Earth) is physically moving further away (up) from the previous height/position it had earlier (eg, with respect to Earth's center). Would there be any 'weird' centrifugal effects from that? Thanks. :)
Ojorf
4.4 / 5 (7) Jul 16, 2018
@Benni

Then why can't we find any of it within our solar system? I know, it's the magic of distance that creates it's obscurity within our solar system, right? Our solar system is just not near enough to a big pocket of this Pop-Cosmology fantasy to make it detectable, right?


No, that's not it at all, " the magic of distance that creates it's obscurity within our solar system" is only in your mind. I suspect you are getting confused between DM and DE.
It is because, just as Fritz Zwicky originally speculated (and the reason it was named Dark Matter), it seems to be matter that ONLY interacts via gravity. Since you don't know anything about gravity I don't expect you to understand the implications of the existence of matter that can only interact via gravity.
So the answer might not make sense to you.

If there is anything you would like explained, please ask.
Reg Mundy
2.3 / 5 (3) Jul 16, 2018

PPS: Your post reminded me that, in our last conversation way back when


Hi RC, Sorry, but I don't want to get sucked back into serious scientific discussion on this site again, its a waste of time. So, briefly, if you assume conservation of angular momentum, and consider that it applies to all the miniscule parts of the Earth which are expanding proportionally whilst retaining their "original" mass, the net result as far as ALL observers in our universe are concerned is that after the passage of a quantum of time absolutely nothing has happened beyond the originally-occurring macro events which continue unabated except for the effects which "scientists" ascribe to "gravity". The "macro" laws of physics still apply as they are actually the statistical aggregation of the countless particles creating the necessary pattern to meet the criteria for selection as the next time quanta from the almost infinite possibilities, those criteria dictated by those same laws of physics.
Benni
2.3 / 5 (6) Jul 16, 2018
Then why can't we find any of it within our solar system? I know, it's the magic of distance that creates it's obscurity within our solar system, right? Our solar system is just not near enough to a big pocket of this Pop-Cosmology fantasy to make it detectable, right?


it seems to be matter that ONLY interacts via gravity. Since you don't know anything about gravity I don't expect you to understand the implications of the existence of matter that can only interact via gravity.
So the answer might not make sense to you.

If there is anything you would like explained, please ask.
........no, I wouldn't want to put you through the pain of yet again trying to explain your impossible DM fantasies that have zero basis within the Laws of Physics as elucidated in Special & General Relativity.

When Pop-Cosmology can't find the 80% of the rest of our own solar system they claim is missing, then it's time to declare FRAUD.
Ojorf
3.3 / 5 (7) Jul 16, 2018
........no, I wouldn't want to put you through the pain of yet again trying to explain your impossible DM fantasies that have zero basis within the Laws of Physics as elucidated in Special & General Relativity.


If you had a grasp of the laws of physics in general, the explanations would be easy to comprehend.
Let's try to find out where the root of your misunderstanding is, let me ask you something.

As you understand "the Laws of Physics as elucidated in Special & General Relativity" what would the implications be of a particle that only interacts via gravity?
How would such a particle behave?
How would masses of such particles behave?
How would the universe look according to "the Laws of Physics as elucidated in Special & General Relativity" if about 23% of the mass and energy of the universe consisted of such particles?
RealityCheck
2 / 5 (8) Jul 16, 2018
@Ojorf.
@Benni
Then why can't we find any of it within our solar system?...
No, that's not it at all, " the magic of distance that creates it's obscurity within our solar system" is only in your mind. I suspect you are getting confused between DM and DE.
It is because, just as Fritz Zwicky originally speculated (and the reason it was named Dark Matter), it seems to be matter that ONLY interacts via gravity....
Mate, say what you like about Benni, he nevertheless has a point regarding your claimed 'exotic' DM 'content' in our solar system (4 times! that of ordinary matter). :)

For years I've urged everyone to consider the implications, for solar system gravitational dynamics, IF that much extra gravitationally active mass/matter WAS in our solar system!

Observed gravitational INTERACTIONS would be MUCH STRONGER; and motions/velocities MUCH MORE EXTREME than observed!

See? There CANNOT BE such 'extra' gravitationally active matter/mass within our solar system. :)
Benni
2.1 / 5 (7) Jul 16, 2018
If you had a grasp of the laws of physics in general, the explanations would be easy to comprehend.
Let's try to find out where the root of your misunderstanding is, let me ask you something.

As you understand "the Laws of Physics as elucidated in Special & General Relativity" what would the implications be of a particle that only interacts via gravity?
How would such a particle behave?
How would masses of such particles behave?
How would the universe look according to "the Laws of Physics as elucidated in Special & General Relativity" if about 23% of the mass and energy of the universe consisted of such particles?


If you had even the smallest grasp of these questions there's not the remotest chance you would believe in this DM fantasy, I unequivocally state this as a professional Scientist/Engineer who does not spend time dwelling in the basements of Cosmologist's favorite fantasies.

jonesdave
3.7 / 5 (6) Jul 16, 2018
I unequivocally state this as a professional Scientist/Engineer


Hahahahahahahahaha!
Benni
2.5 / 5 (8) Jul 16, 2018
For years I've urged everyone to consider the implications, for solar system gravitational dynamics, IF that much extra gravitationally active mass/matter WAS in our solar system!

Observed gravitational INTERACTIONS would be MUCH STRONGER; and motions/velocities MUCH MORE EXTREME than observed!

See? There CANNOT BE such 'extra' gravitationally active matter/mass within our solar system.


......but what you miss here is that COSMOLOGY plays by different rules than those of the Observable Laws of Physics, it's a game, not a science, akin to VIRTUAL REALITY.

For example Cosmologists believe a neutron has a half-life decay rate, they don't know it doesn't & Ojo has been one of those here making statements to the contrary, he sets himself up for his own failures to comprehend the subject material then goes on name calling rants when you don't agree with the fallacies of his reasoning, same as Fritz Zwicky did in labeling Einstein a "spherical bastard".
Ojorf
3.7 / 5 (3) Jul 17, 2018
If you had even the smallest grasp of these questions there's not the remotest chance you would believe in this DM fantasy, I unequivocally state this as a professional Scientist/Engineer who does not spend time dwelling in the basements of Cosmologist's favorite fantasies.


I bow to your superior knowledge as a "professional Scientist/Engineer" and beg for your help.
Please would you use your in-depth knowledge of "the Laws of Physics as elucidated in Special & General Relativity" to explain to me these mysteries?
Our hero Einstein loved thought experiments. Please explain to me how a bunch of hypothetical particles that only interact via gravity would behave? What would happen if they were mixed in with ordinary matter?
Please help me out here Benni, I want to learn.
granville583762
1 / 5 (2) Jul 17, 2018
After 9 Rounds! The last one Standing
RealityCheck> IF that much extra gravitationally active mass WAS in our solar system Observed gravitational INTERACTIONS would be MUCH STRONGER; and motions/velocities MUCH MORE EXTREME than observed! See? There CANNOT BE such 'extra' gravitationally active matter/mass within our solar system

Bennie> what you miss here is that COSMOLOGY plays by different rules than those of the Observable Laws of Physics, it's a game, not a science, akin to VIRTUAL REALITY. For example Cosmologists believe a neutron has a half-life decay rate, they don't know it doesn't & Ojo has been one of those here making statements to the contrary, he sets himself up for his own failures to comprehend the subject material then goes on name calling rants when you don't agree with the fallacies of his reasoning, same as Fritz Zwicky did in labeling Einstein a "spherical bastard".

Finally Benni, Ojorf and company including pottymouth have admitted defeat!
granville583762
3 / 5 (2) Jul 17, 2018
Milkyway Stars contain no darkmatter

Concerning matter and darkmatter, the gravitational force and therefore the gravitational constant is equally prevalent in both types of matter where the force of gravity is equally proportional to mass where matter and darkmatter are equally attracted to one another
RealityCheck> IF that much extra gravitationally active mass WAS in our solar system Observed gravitational INTERACTIONS would be MUCH STRONGER

Whether we like it or not the scientific prevalent view is Gravities equal dominance over all types of matter and its absolute velocity to that of Light

The undeniable fact is that the only gravitational force in the vacuum is emanating from galaxies which yet again the prevalent scientific view is they consist only of matter because there is no darkmatter in galaxies as proved by our sun as typical star constructed from galactic matter containing no darkmatter!
granville583762
3 / 5 (2) Jul 17, 2018
9 Rounds! The last one Standing
RealityCheck> that much extra gravitationally active mass WAS in our solar system Observed gravitational INTERACTIONS would be MUCH STRONGER and motions/velocities MUCH MORE EXTREME than observed! See There CANNOT BE such extra gravitationally active matter/mass within our solar system

Bennie> COSMOLOGY plays by different rules than those of Observable Laws of Physics a game not a science akin to VIRTUAL REALITY. Cosmologists believe a neutron has a half-life decay rate they don't know it doesn't & Ojo has been one of those making statements to the contrary he sets himself up for his own failures to comprehend the subject material then goes on name calling rants when you don't agree with the fallacies of his reasoning same as Fritz Zwicky did labelling Einstein a spherical bastard

granville583762> Finally Benni, Ojorf and company including pottymouth have admitted defeat!

Thanks Ojorf * 1 / 5 (1) nice complement
Benni
2.1 / 5 (7) Jul 17, 2018
Please explain to me how a bunch of hypothetical particles that only interact via gravity would behave? What would happen if they were mixed in with ordinary matter?
Please help me out here Benni, I want to learn.


You already answered your own question: "explain to me how a bunch of hypothetical particles"

Your biggest problem is your inability in responding & explaining your own "hypothetical"s. You Pop-Cosmologists with absolutely no educational background in Nuclear Physics invent silly hypotheticals, then expect those of us who are professionals in science/engineering to explain things that have no basis in science.
granville583762
5 / 5 (2) Jul 17, 2018
The last act of desperation dark matter talks to normal matter!
This last act of desperation to save darkmatter by consolidation with the mass of the vacuum, namely matter proving what we already know, matter and darkmatter are universally attracted by gravity

But this is not what the researchers are saying, the article says - Yu explained that PandaX-II assumes dark matter talks to normal matter – I ask you, we have highly qualified and presumably adequately enumerated scientists seriously discussing darkmatter talking to matter, the mind boggles at the possible conversations that are taking place

The conversation comes down to earth somewhat by explaining it is gravity interacting equally such that matter and darkmatter can coexist as single combination of matter because darkmatters properties are the as same matter, such that atomically speaking darkmatter is identical to matter – after all this time darkmatter is actually matter – a master stroke of Obfuscation!
granville583762
5 / 5 (1) Jul 17, 2018
Round 10 to Benni, the hypotheticals crowd the diminishing darkmatter corner!
Ojorf> Please explain to me how a bunch of hypothetical particles that only interact via gravity would behave? What would happen if they were mixed in with ordinary matter?

I did not notice this statement Benni, considering the state of affairs darkmatter has sunk into, such that it is so identical to matter darkmatter does not exist; it puts Ojorf's statement "Please explain to me how a bunch of hypothetical particles that only interact via gravity would behave? What would happen if they were mixed in with ordinary matter?" in to a completely new context Benni, how can one answer the question in the first instance if darkmatter exist as it is hypothetical, but seeing as darkmatter no longer exist it is no longer a valid question and an even less valid as a hypothetical question
Only the heavy weights stand 12 rounds Benni, everyone else with their theories has fallen to ways side!
Benni
1 / 5 (4) Jul 17, 2018
I ask you, we have highly qualified and presumably adequately enumerated scientists seriously discussing darkmatter talking to matter
.........no we have no such thing going on here granDy, just the standard & predictable fantasies all too common in this guy's world of Pop-Cosmology.

the mind boggles at the possible conversations that are taking place
.......Oh, you mean like Jonesy's & Ojo's concept of NEUTRON HALF-LIFE & how one whole neutron can morph into half-a-neutron, and then decay into one-quarter of a neutron, then an eighth...... ad infinitum ?

jonesdave
3.4 / 5 (5) Jul 17, 2018
Oh, you mean like Jonesy's & Ojo's concept of NEUTRON HALF-LIFE & how one whole neutron can morph into half-a-neutron, and then decay into one-quarter of a neutron, then an eighth...... ad infinitum ?


Christ you're thick! Stick to mopping floors, dumbo.

Benni
1.8 / 5 (5) Jul 17, 2018
Oh, you mean like Jonesy's & Ojo's concept of NEUTRON HALF-LIFE & how one whole neutron can morph into half-a-neutron, and then decay into one-quarter of a neutron, then an eighth...... ad infinitum ?


Christ you're thick! Stick to mopping floors, dumbo.


Oh? So what do you believe? Maybe beta-decay doesn't work that way? If you do, you never knew it until I explained it to you sometime back. I wonder if Pop-Cosmologist Hai-Bo Yu knows what I've taught you, and many others here, about neutron decay rate of 15 minutes?
jonesdave
3.7 / 5 (6) Jul 17, 2018
Oh, you mean like Jonesy's & Ojo's concept of NEUTRON HALF-LIFE & how one whole neutron can morph into half-a-neutron, and then decay into one-quarter of a neutron, then an eighth...... ad infinitum ?


Christ you're thick! Stick to mopping floors, dumbo.


Oh? So what do you believe? Maybe beta-decay doesn't work that way? If you do, you never knew it until I explained it to you sometime back. I wonder if Pop-Cosmologist Hai-Bo Yu knows what I've taught you, and many others here, about neutron decay rate of 15 minutes?


I know how B-decay works you idiot. We spent a whole thread explaining it to your idiotic self. That was the whole irony of that thread, you moron - somebody who fantasises, in his Dunning-Kruger addled mind, about being a nuclear engineer, and doesn't even understand a high school subject like radioactive decay!
You're an idiot, as you've demonstrated numerous times. My guess? You're still in grade school.
Benni
1.8 / 5 (5) Jul 17, 2018
I know how B-decay works you idiot. We spent a whole thread explaining it to you


It wasn't beta decay you were stumbling & fumbling around trying to explain, it was your convoluted concept of NEUTRON HALF-LIFE you were trying to pass off as only Pop-Cosmology could create fantasies for such distortions.
jonesdave
4 / 5 (4) Jul 17, 2018
I know how B-decay works you idiot. We spent a whole thread explaining it to you


It wasn't beta decay you were stumbling & fumbling around trying to explain, it was your convoluted concept of NEUTRON HALF-LIFE you were trying to pass off as only Pop-Cosmology could create such distortions.


Go away you uneducated idiot. You do not understand the concept of half-life, as you amply proved previously. You are too thick to understand even very basic science. What the hell makes you think you can come on here, making a complete arse of yourself, thread after thread, on stuff that is beyond your extremely limited intellectual capacity to understand? You're a bloody moron.
jonesdave
4 / 5 (4) Jul 17, 2018
It wasn't beta decay you were stumbling & fumbling around trying to explain, it was your convoluted concept of NEUTRON HALF-LIFE you were trying to pass off as only Pop-Cosmology could create such distortions.


And there, in a nutshell, is an example of the scientific illiteracy I'm talking about from this loon. Hey, Benni, what do you think beta-decay is?

A free neutron will decay with a half-life of about 10.3 minutes but it is stable if combined into a nucleus. ***This decay is an example of beta decay*** with the emission of an electron and an electron antineutrino.

http://hyperphysi...ton.html

Just plain stupid.

Benni
1.8 / 5 (5) Jul 17, 2018
It wasn't beta decay you were stumbling & fumbling around trying to explain, it was your convoluted concept of NEUTRON HALF-LIFE you were trying to pass off as only Pop-Cosmology could create such distortions.


And there, in a nutshell, is an example of the scientific illiteracy I'm talking about from this loon. Hey, Benni, what do you think beta-decay is?


A free neutron will decay with a half-life of about 10.3 minutes but it is stable if combined into a nucleus. ***This decay is an example of beta decay*** with the emission of an electron and an electron antineutrino.


Free unbound neutron decay rate is not measured in half-life increments,

Just a continuum of your Pop-Cosmology fantasy, beta decay has nothing to do with radio-active half life in the real world of nuclear physics, only in your unreal world of Pop-Cosmology fantasies, 10.3 minutes being just another one of those fantasies mis-educated people like you take so seriously.
jonesdave
3.4 / 5 (5) Jul 17, 2018
Free unbound neutron decay rate is not measured in half-life increments,


Yes it is, loser. Get an education. Why do you think it is called a half-life, you moron?
jonesdave
3.4 / 5 (5) Jul 17, 2018
.......beta decay has nothing to do with radio-active half life in the real world of nuclear physics,


Jesus H. Christ. Anybody still believe that this nutter has ever qualified in anything to do with nuclear physics? Does anybody else want to put the knife in, before I do?
granville583762
2.3 / 5 (3) Jul 17, 2018
I ask you, we have highly qualified and presumably adequately enumerated scientists seriously discussing darkmatter talking to matter
no we have no such thing going on here granDy, just the standard & predictable fantasies all too common in this guy's world of Pop-Cosmology.
the mind boggles at the possible conversations that are taking place
Oh, you mean like Jonesy's & Ojo's concept of NEUTRON HALF-LIFE & how one whole neutron can morph into half-a-neutron, and then decay into one-quarter of a neutron ad infinitum ?

Concerning the Neutron and its Magic half-life with its mean life is 15min, theoretically the Sun could burn its last hydrogen molecule, still are Neutron stubbornly refuse's to decay
Which comes to Albert's little problem concerning the same, namely the Muon decaying to electrons and neutrinos it has this same Magic half-life 2.2x10-06s of mean-life
I don't see the same criteria applied to the muon half-life, apparently it just decays
granville583762
2 / 5 (3) Jul 17, 2018
Muons do not decay in motion
I think the criteria for half life conditionally laid down was 50:50 chance of decay as this should apply to any particle undergoing decay through the exponential half-life life involving electrons in the decay process. But when it comes to Albert and his cherished theory applied to the muon the half-life apparently takes on Magic properties and decays precisely when Albert says so in 2.2x10-06s.
The reality is muons do not decay in motion as they travel practically at C they cover the same distance in 2.2x10-06s as photons the reason they reach the upper atmosphere to the ground in the same time as light is they do not decay on the move, they only decay when stationary!

granville583762
2 / 5 (3) Jul 17, 2018
Muons do not decay in motion
I think the criteria for half life conditionally laid down was 50:50 chance of decay as this should apply to any particle undergoing decay through the exponential half-life life involving electrons in the decay process. But when it comes to Albert and his cherished theory applied to the muon the half-life apparently takes on Magic properties and decays precisely when Albert says so in 2.2x10-06s.
The reality is muons do not decay in motion as they travel practically at C they cover the same distance in 2.2x10-06s as photons the reason they reach the upper atmosphere to the ground in the same time as light is they do not decay on the move, they only decay when stationary!

Now jonesdave you have to prove it, in preference to giving it a single star
jonesdave
2.3 / 5 (3) Jul 17, 2018

Now jonesdave you have to prove it, in preference to giving it a single star


No, you f***ing moron, I do not need to prove it, idiot. It has already been proven by far smarter people than you or I, dummy. Yes?
Do they do Grammar Schools in Yorkshire? If so, I would suggest attending one, you eejit. Stop posting about stuff that is obviously way beyond your ability to understand, yes? i.e. kindergarten level.
Now, bugger off, there's a good chap. You are becoming awfully tiresome.
granville583762
2.3 / 5 (3) Jul 17, 2018
Faith, Gospel and Religion seem to have considerable prevalence of late

I am not saying do not give it a single star J.D, it is just that I am becoming accustomed to accepting as Gospel certain aspects of theories without question and we should not be bringing the Gospel into Albert's theories. To date where ever any one points to proof positive on these questions J.D. It always ends up in accepting certain aspects of the answer requiring blind unquestioning Faith, and Faith is not a Religion I expect to be practicing with Albert's theories
Thank you for replying
Benni
2.3 / 5 (6) Jul 17, 2018
Free unbound neutron decay rate is not measured in half-life increments,


Yes it is, loser. Get an education. Why do you think it is called a half-life, you moron?
......half a neutron, HERE COMES JONESY.

Making it plain why you studied Anthropology rather than a field of endeavor where you need to know how to solve Differential Equations.
jonesdave
2.3 / 5 (3) Jul 17, 2018
Faith, Gospel and Religion seem to have considerable prevalence of late

I am not saying do not give it a single star J.D, it is just that I am becoming accustomed to accepting as Gospel certain aspects of theories without question and we should not be bringing the Gospel into Albert's theories. To date where ever any one points to proof positive on these questions J.D. It always ends up in accepting certain aspects of the answer requiring blind unquestioning Faith, and Faith is not a Religion I expect to be practicing with Albert's theories
Thank you for replying


Then read some f***ing science, yes? Stop posting crap on here that can be refuted by a half decent high school student, yes? You are as bad as the moron Benni. All talk, no education. Now, piss off, and get an education, yes? Christ you people are f***ing tiresome. Idiots.
jonesdave
2.3 / 5 (3) Jul 17, 2018
Making it plain why you studied Anthropology rather than a field of endeavor where you need to know how to solve Differential Equations.


Sorry? Where did I do anthropology, you f***wit? I have studied it, dipsh*t, yes? And you have been shown to be mathematically illiterate. Yes? Want me to post the link to the image? It's still on imagebam, I believe. You cannot do differential equations, you idiot. You are a janitor! Correct? Now go away, little boy. Idiot.

jonesdave
2.3 / 5 (3) Jul 17, 2018
Free unbound neutron decay rate is not measured in half-life increments,


Yes it is, loser. Get an education. Why do you think it is called a half-life, you moron?
......half a neutron, HERE COMES JONESY.

Making it plain why you studied Anthropology rather than a field of endeavor where you need to know how to solve Differential Equations.


This is the f***wit who couldn't do simple maths to figure out a Schwarzschild radius, even though he was given every parameter! Benni, you are a waster, correct? Get back to mopping the floors, dear. About all you're good for, yes? Maths is beyond you, dear. So is science. Now, go play nicely with the rest of the inmates.
granville583762
not rated yet Jul 17, 2018
I know I said I am not saying do not give it a single star, but without answering you weren't supposed to give a single star, it's one of those grammar school pranks J.D.
IwinUlose
5 / 5 (1) Jul 18, 2018
Ojorf
1 / 5 (1) Jul 18, 2018
You already answered your own question: "explain to me how a bunch of hypothetical particles"

Your biggest problem is your inability in responding & explaining your own "hypothetical"s.


Ha, ha ha. Add "thought experiment" to the long list of subjects Benni is unable to comprehend.

I did not answer any questions dear Benni. Answers do not have question marks at the end. I asked YOU a few simple questions.
Loop up "thought experiment", read my questions again, see if you can give some simple answers in your own words. It would really be appreciated. Prove you status as a "professional Scientist/Engineer" and your mastery of linear equations.
LOL
Ojorf
5 / 5 (1) Jul 18, 2018
Thanks Ojorf * 1 / 5 (1) nice complement


Oh, stop complaining, I've voted every sensible post of yours a 5.
granville583762
5 / 5 (1) Jul 18, 2018
9 Rounds! The last one Standing
Thanks Ojorf * 1 / 5 (1) nice complement

Ojorf> Oh, stop complaining, I've voted every sensible post of yours a 5.

I wasn't complaining Ojorf, you genuinely gave a compliment, it was a light hearted post!
granville583762
4 / 5 (1) Jul 18, 2018
The unspoken etiquette
I know I said I am not saying do not give it a single star, but without answering you weren't supposed to give a single star, it's one of those grammar school pranks J.D.

Like the Emperor and his suit of clothes, everyone bar one knew of his new suit of clothes J.D.
The single sole was not supposed to say anything about the Emperor and his suit of clothes because even though he did not know about his new suit, the unspoken etiquette told him to stay quite; which is why without answering the question implied everyone would not elaborate as to the reason why if it was not awarded a single star J.D.
granville583762
4 / 5 (1) Jul 18, 2018
Light hearted posts
9 Rounds! The last one Standing
Thanks Ojorf * 1 / 5 (1) nice complement

Ojorf> Oh, stop complaining, I've voted every sensible post of yours a 5.

I wasn't complaining Ojorf, you genuinely gave a compliment, it was a light hearted post!

The implication Ojorf is when it is a light hearted post; you can't down vote a light hearted comment, it's a meaningless use of the rating system for when it's used to actually rate a poorly written comment which deservedly deserves a single star – because Ojorf the rating system is being used to maintain a cliché, not poorly written comments.
antialias_physorg
3.7 / 5 (3) Jul 18, 2018
as a "professional Scientist/Engineer"

Wow...first he tries to pass himself off as an engineer...then as an electrical engineer, then as a nuclear engineer...then as a scientist? What's next? A god?

Maybe he should try to pass himself off as a freshman in high school.

Naah...I wouldn't believe that either.
granville583762
5 / 5 (1) Jul 18, 2018
The infamous half a neutron and the 50-50 half-life decay
As this continued criticism of Bennies theories - the sticking point in all everyone objections appears to be exponential decay and the chance 50-50 half-life decay of the infamous neutron not decaying in 15minutes but probably, longer but when it comes to Albert's muon which travelling at practically the speed of light covers a greater distance than its 50-50 half-life this fact is ignored and it decays in 2.2x10-06s.
granville583762
5 / 5 (1) Jul 19, 2018
To decay or not to decay

The stark comparisons of the muon versus the neutron
Neutrons and Muons decay where both appear to be mediated by the nuclear weak force, both are undergoing exponential decay with a 50-50 chance of decay where both have half-lifes

If the acolytes would care to explain why the constant barrage on Bennies half a neutron; that it does not decay instantly at the 15minute point where as the same acolytes accept Albert's assertion the muon undergoes instant decay in 2.2x10-06seconds

Both the neutron and muon are atomic particles; both are mediated by the same nuclear forces, both decay into electrons and neutrinos and both experience exponential 50-50 decay

In this respect Benni is on a level playing field with Albert

granville583762
5 / 5 (1) Jul 19, 2018
The acolytes on Bennies Rule
Consequence of muon decay is the stalwart of Albert's length contraction
Albert's theories are subject to the same ordinary mundane every day rules as every ones else's
Neutrons ejected at relativistic velocities from nuclear reactions where they undergo 50-50 half-life decay
Muons ejected at relativistic velocities from Pions undergoing atomic reactions where they undergo 50-50 half-life decay
Similarities between muons and neutrons undergoing 50-50 half-life decay are identical in every respect in relativistic velocity, in 50-50 half-life decay and in elemental decay products
The contested point; at what point does the neutron or muon actually physically decay.
Common sense says all decay in same time within their half-life decay time
This means the muon does not decay in 2.2x10-06seconds just as the neutron does not decay in 881s which is why the muon can reach the ground from the upper atmosphere, nothing to do with length contraction
granville583762
5 / 5 (1) Jul 19, 2018
The acolytes on Bennies Rule
The alternative is the acolytes on Bennies Rule accept the fact Albert has already accepted that the neutron decays in 881seconds just as the muon decays in 2.2x10-06seconds, unless the acolytes are saying Albert is wrong in his assertion that by the muon decaying in 2.2x10-06seconds there by proves length contraction?
Unfortunately in real world down to earth realities the acolytes cannot have it both ways!

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