6 ms·

Gamma rays from the Milky Way's core look ever more like signs of dark matter

51 points by universe520 11y ago

cgriswald 11y ago
My high school physics professor had a motto: "Good enough is not good enough." This was generally in response to the imprecision of lazy students who would say to themselves or their lab partners, "Good enough." It's something I've carried with me in life in a lot of contexts. So it was fun seeing Dr. Goodenough's name in the article.
- noobermin 11y ago
  Funny, I didn't see that in her name.
- ISL 11y ago
  Alas, her name is pronounced ~Good-en-know, not Good-en-nuff.
pc2g4d 11y ago
"and particle physicists will have six times more stuff to study than they had before." Can anyone out there explain this statement for us non-physicists?
- scentoni 11y ago
  There's roughly five or six times as much dark matter in the universe as there is conventional matter.
- jjtheblunt 11y ago
  Um, folks not producing results begging for continued government funding, without results being required.
- jaskerr 11y ago
  They're echoing a statement made in the third paragraph: "Everything from the motions of galaxies to calculations about what sort of universe came out of the Big Bang says it [dark matter] must exist—and must outweigh familiar, atomic, matter by about six to one."
hoodoof 11y ago
I know this betrays my ignorance but it just seems that dark matter is a rather implausible explanation for the apparent evidence of additional gravitational force being exerted. "must outweigh familiar, atomic, matter by about six to one" but despite our best efforts it cannot be detected but there's vast amounts of it. It seems to me there must be a better explanation because so far this one (i.e. it's there but we just can't detect it at all) just doesn't make sense.
- svachalek 11y ago
  It's not theoretically undetectable, just very hard to detect, to the point that we haven't yet been able to do it. This article suggests that finally, we may be able to see it other than via gravitational effects. For a long time I also subscribed to the idea that the missing matter was better explained by faulty math, somewhere, but as our observations get better it's looking more and more like there's really something there, that behaves independently and differently than the matter we know.
  - hoodoof 11y ago
    I don't question that the effect is there. I just wonder if it isn't a side effect of some other (not understood) aspect of the universe rather than the result of the behaviour of some particle. To illustrate, gravity per se doesn't exist, it's the outcome of the bending of space towards mass. So it's effect is real but it's not because some sort of gravitional particle is acting.
- bashinator 11y ago
  We have in fact detected one type of dark matter - neutrinos. They aren't sufficient to account for the mass needed to explain observations, but they are definitely dark matter in that they do not interact electromagnetically with regular matter. The problem with modified gravity, is that it requires a lot more theoretical complexity to explain observations like the Bullet cluster and galaxy rotation, and the large-scale distribution of matter in the observable universe. Ie. a modified gravity theory that works for one of those observations, fails for others. Slow, massive dark matter clouds explain all of them quite nicely.
emu 11y ago
Treat this article with skepticism. I think the journalist has badly misjudged the current consensus in the field when they say: "There are still a few die-hards who do not believe in hooperons. They suggest that if an ensemble of millisecond pulsars (dead stars that rotate hundreds of times a second) were buried in the Milky Way’s middle, that might do the trick." The way I hear it, a population of new point sources is a better match for the Fermi data than dark matter --- the excess is "clumpy", indicating point sources, when you would expect a dark matter signal to be diffuse.
mirimir 11y ago
Also see http://www.scientificamerican.com/article/dark-matter-explosions-at-milky-way-core/ http://www.scientificamerican.com/article/dark-matter-explos... Edit: I find this 2011 paper, but nothing newer: http://arxiv.org/pdf/1010.2752v3.pdf http://arxiv.org/pdf/1010.2752v3.pdf Maybe someone can point to their latest stuff.
poelzi 11y ago
Dark Matter is apparently 84.54% of our Universe. If this is so abandoned, why did the millions we spend looking for it did not yield anything ? Lets see: http://arxiv.org/pdf/physics/0612201.pdf http://arxiv.org/pdf/physics/0612201.pdf http://arxiv.org/pdf/1004.0716v3.pdf http://arxiv.org/pdf/1004.0716v3.pdf If you go through the list of papers on the Michelson-Morley experiment, you will see that it is not that clear. In fact, they did a lot of things wrong then. Averaged values that should have not been, missing information about the movement of the solar system around the galaxy core (~360 km/s), gas mode instead of vacuum,... There are many critical papers published over the years: http://arxiv.org/find/all/1/all:+AND+michelson+morley/0/1/0/all/0/1?skip=0&query_id=d6e27eb164d5921a http://arxiv.org/find/all/1/all:+AND+michelson+morley/0/1/0/... This is a very nice list of better experiments, looking into those is very interesting: http://www.helical-structures.org/new_evidences/modern-ether-drift-exp/ether-drift-exp.pdf http://www.helical-structures.org/new_evidences/modern-ether... Einstein only later understood, that general Relativity without aether is unthinkable (Sidelights on Relativity): """ Recapitulating, we may say that according to the general theory of relativity space is endowed with physical qualities; in this sense, therefore, there exists an ether. According to the general theory of relativity space without ether is unthinkable; for in such space there not only would be no propagation of light, but also no possibility of existence for standards of space and time (measuring-rods and clocks), nor therefore any space-time intervals in the physical sense. But this ether may not be thought of as endowed with the quality characteristic of ponderable media, as consisting of parts which may be tracked through time. The idea of motion may not be applied to it. """ He did not need aether for SR, but GR without aether, simply does not make sense. Also radial waves as predicted by Lord Kelvin and discovered by Tesla are not really understandable without. You can explain many virtual particles by creating a zoo like the standard model did, but radial waves you can't. Dark Matter is the aether, without it's mass, spiral galaxies and many other cosmological phenomena are not explainable - or at least not classical. The problem with most aether theories is, that they assume it as some sort of superfluid, or some special substance, which both do not make so much sense, as the complexity of the vacuum is simply to great. It must at least implement all virtual particles (β+/β-/photons/...), electric and magnet fields (Hertz & Tesla waves, as both exist),... The BSM-SG model has a completely different aether model, instead of some special substance, it is made of the same building materials as protons/electrons, just in a much smaller and different geometric structure. It has only one fundamental force and 2 very simple fundamental particles (balls). It becomes clear, that already quite large crystals, that look like prisms, under this one law of attraction, build a grid that looks like a 3d honey web. In this grid, you can find all the physical properties we can measure. Electric and Magnet Fields, Speed of Light, Photons, Vacuum Fluctuations, Gravity, Coulomb Barrier, Quantum Entanglement, Virtual Particles (without rest-mass).... Of course, many of those are iterations between the extremely complex geometrical structure of electrons/protons/neutrons and the Cosmic Lattice as its called in BSM-SG. Best physics book I read and most sensible unified theory I have encountered so far: http://www.amazon.com/Basic-Structures-Matter-Supergravitation-Unified/dp/1412083877 http://www.amazon.com/Basic-Structures-Matter-Supergravitati... Needs an open mind tho and some months of heavy thinking for really getting into this theory, but once you grasp the basic interactions, geometric structures etc the universe starts to make so much sense. So far, every phenomena I encountered was explainable after some minutes-days of thinking and I always came to the same conclusion as Stoyan Sarg. The universe is classic logical :)

51 points by universe520 11y ago

My high school physics professor had a motto: "Good enough is not good enough." This was generally in response to the imprecision of lazy students who would say to themselves or their lab partners, "Good enough." It's something I've carried with me in life in a lot of contexts. So it was fun seeing Dr. Goodenough's name in the article.

noobermin 11y ago
Funny, I didn't see that in her name.
ISL 11y ago
Alas, her name is pronounced ~Good-en-know, not Good-en-nuff.

pc2g4d 11y ago

"and particle physicists will have six times more stuff to study than they had before." Can anyone out there explain this statement for us non-physicists?

scentoni 11y ago
There's roughly five or six times as much dark matter in the universe as there is conventional matter.
jjtheblunt 11y ago
Um, folks not producing results begging for continued government funding, without results being required.
jaskerr 11y ago
They're echoing a statement made in the third paragraph: "Everything from the motions of galaxies to calculations about what sort of universe came out of the Big Bang says it [dark matter] must exist—and must outweigh familiar, atomic, matter by about six to one."

hoodoof 11y ago

I know this betrays my ignorance but it just seems that dark matter is a rather implausible explanation for the apparent evidence of additional gravitational force being exerted. "must outweigh familiar, atomic, matter by about six to one" but despite our best efforts it cannot be detected but there's vast amounts of it. It seems to me there must be a better explanation because so far this one (i.e. it's there but we just can't detect it at all) just doesn't make sense.

svachalek 11y ago
It's not theoretically undetectable, just very hard to detect, to the point that we haven't yet been able to do it. This article suggests that finally, we may be able to see it other than via gravitational effects. For a long time I also subscribed to the idea that the missing matter was better explained by faulty math, somewhere, but as our observations get better it's looking more and more like there's really something there, that behaves independently and differently than the matter we know.
- hoodoof 11y ago
  I don't question that the effect is there. I just wonder if it isn't a side effect of some other (not understood) aspect of the universe rather than the result of the behaviour of some particle. To illustrate, gravity per se doesn't exist, it's the outcome of the bending of space towards mass. So it's effect is real but it's not because some sort of gravitional particle is acting.
bashinator 11y ago
We have in fact detected one type of dark matter - neutrinos. They aren't sufficient to account for the mass needed to explain observations, but they are definitely dark matter in that they do not interact electromagnetically with regular matter. The problem with modified gravity, is that it requires a lot more theoretical complexity to explain observations like the Bullet cluster and galaxy rotation, and the large-scale distribution of matter in the observable universe. Ie. a modified gravity theory that works for one of those observations, fails for others. Slow, massive dark matter clouds explain all of them quite nicely.

emu 11y ago

Treat this article with skepticism. I think the journalist has badly misjudged the current consensus in the field when they say: "There are still a few die-hards who do not believe in hooperons. They suggest that if an ensemble of millisecond pulsars (dead stars that rotate hundreds of times a second) were buried in the Milky Way’s middle, that might do the trick." The way I hear it, a population of new point sources is a better match for the Fermi data than dark matter --- the excess is "clumpy", indicating point sources, when you would expect a dark matter signal to be diffuse.

mirimir 11y ago

Also see http://www.scientificamerican.com/article/dark-matter-explosions-at-milky-way-core/ http://www.scientificamerican.com/article/dark-matter-explos... Edit: I find this 2011 paper, but nothing newer: http://arxiv.org/pdf/1010.2752v3.pdf http://arxiv.org/pdf/1010.2752v3.pdf Maybe someone can point to their latest stuff.

poelzi 11y ago

Dark Matter is apparently 84.54% of our Universe. If this is so abandoned, why did the millions we spend looking for it did not yield anything ? Lets see: http://arxiv.org/pdf/physics/0612201.pdf http://arxiv.org/pdf/physics/0612201.pdf http://arxiv.org/pdf/1004.0716v3.pdf http://arxiv.org/pdf/1004.0716v3.pdf If you go through the list of papers on the Michelson-Morley experiment, you will see that it is not that clear. In fact, they did a lot of things wrong then. Averaged values that should have not been, missing information about the movement of the solar system around the galaxy core (~360 km/s), gas mode instead of vacuum,... There are many critical papers published over the years: http://arxiv.org/find/all/1/all:+AND+michelson+morley/0/1/0/all/0/1?skip=0&query_id=d6e27eb164d5921a http://arxiv.org/find/all/1/all:+AND+michelson+morley/0/1/0/... This is a very nice list of better experiments, looking into those is very interesting: http://www.helical-structures.org/new_evidences/modern-ether-drift-exp/ether-drift-exp.pdf http://www.helical-structures.org/new_evidences/modern-ether... Einstein only later understood, that general Relativity without aether is unthinkable (Sidelights on Relativity): """ Recapitulating, we may say that according to the general theory of relativity space is endowed with physical qualities; in this sense, therefore, there exists an ether. According to the general theory of relativity space without ether is unthinkable; for in such space there not only would be no propagation of light, but also no possibility of existence for standards of space and time (measuring-rods and clocks), nor therefore any space-time intervals in the physical sense. But this ether may not be thought of as endowed with the quality characteristic of ponderable media, as consisting of parts which may be tracked through time. The idea of motion may not be applied to it. """ He did not need aether for SR, but GR without aether, simply does not make sense. Also radial waves as predicted by Lord Kelvin and discovered by Tesla are not really understandable without. You can explain many virtual particles by creating a zoo like the standard model did, but radial waves you can't. Dark Matter is the aether, without it's mass, spiral galaxies and many other cosmological phenomena are not explainable - or at least not classical. The problem with most aether theories is, that they assume it as some sort of superfluid, or some special substance, which both do not make so much sense, as the complexity of the vacuum is simply to great. It must at least implement all virtual particles (β+/β-/photons/...), electric and magnet fields (Hertz & Tesla waves, as both exist),... The BSM-SG model has a completely different aether model, instead of some special substance, it is made of the same building materials as protons/electrons, just in a much smaller and different geometric structure. It has only one fundamental force and 2 very simple fundamental particles (balls). It becomes clear, that already quite large crystals, that look like prisms, under this one law of attraction, build a grid that looks like a 3d honey web. In this grid, you can find all the physical properties we can measure. Electric and Magnet Fields, Speed of Light, Photons, Vacuum Fluctuations, Gravity, Coulomb Barrier, Quantum Entanglement, Virtual Particles (without rest-mass).... Of course, many of those are iterations between the extremely complex geometrical structure of electrons/protons/neutrons and the Cosmic Lattice as its called in BSM-SG. Best physics book I read and most sensible unified theory I have encountered so far: http://www.amazon.com/Basic-Structures-Matter-Supergravitation-Unified/dp/1412083877 http://www.amazon.com/Basic-Structures-Matter-Supergravitati... Needs an open mind tho and some months of heavy thinking for really getting into this theory, but once you grasp the basic interactions, geometric structures etc the universe starts to make so much sense. So far, every phenomena I encountered was explainable after some minutes-days of thinking and I always came to the same conclusion as Stoyan Sarg. The universe is classic logical :)