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Dark matter is a stuff that exists, we’re pretty sure, and some explanations for what it is would involve expansions for the standard model; seeing if one of th

Dark matter is a stuff that exists, we’re pretty sure, and some explanations for what it is would involve expansions for the standard model; seeing if one of those explanations is right is therefore a (supposedly) promising avenue for post-standard model physics.

sinuhe69 8y ago
Maybe one should read more before downgrading other people’ comment as nonsense. Excerpts from Wikipedia (text in square brackets are my): Dark matter is a hypothetical form of matter that is thought to account for approximately 85% of the matter in the universe...[speaks the existence of dark matter existence is not proven, is not even part of the standard model!] [...] Its presence is implied in a variety of astrophysical observations, including gravitational effects that cannot be explained unless more matter is present than can be seen. […] The primary evidence for dark matter is that calculations show that many galaxies would fly apart instead of rotating, or would not have formed or move as they do, if they did not contain a large amount of unseen matter.[2] Other lines of evidence include observations in gravitational lensing,[3] from the cosmic microwave background, from astronomical observations of the observable universe's current structure, from the formation and evolution of galaxies, from mass location during galactic collisions,[4] and from the motion of galaxies within galaxy clusters. [so mismatch in gravitational effect with Einstein General Relativity is the only reason why people think there “must” be dark matter out there. Imagining dark matter would help to keep Einstein General Relativity correct in its current form, in other words it’s a HACK!] […] Although the existence of dark matter is generally accepted by the scientific community, some astrophysicists, intrigued by certain observations that do not fit the dark matter theory, argue for various modifications of the standard laws of general relativity, such as modified Newtonian dynamics, tensor–vector–scalar gravity, or entropic gravity. These models attempt to account for all observations without invoking supplemental non-baryonic matter. [means without the need for the hypothetical, non-observable dark matter. And because the standard model can not explain gravity, dark matter or modified gravity theory has nothing to do with the standard model as stated in my original comment]
- maxander 8y ago
  For what it's worth, I didn't downvote you- but you should realize the gap between what your Wikipedia source says and what you originally asserted. Yes, Wikipedia is right that the existence of dark matter isn't proven, and it's also true that there's no proven connection to the Standard Model; it's also true, as I said, that scientists are pretty sure that it does exist (the alternate theories are widely regarded as long shots.) And if it exists, this novel form of matter would need to be fit into the Standard Model somewhere, since that is intended to describe all forms of matter. Incidentally, I also think you're getting your history of science confused; the "cosmological constant" term Einstein used to make relativity consistent with his belief in a static, non-expanding universe was a "hack" (he himself wound up admitting it was unjustified.) But that's entirely unrelated to dark matter. Similar modern theories to the cosmological constant have been termed "dark energy," but the use of the word "dark" in both doesn't imply a real connection- it simply means that they each haven't been directly observed.

sinuhe69 8y ago

Maybe one should read more before downgrading other people’ comment as nonsense. Excerpts from Wikipedia (text in square brackets are my): Dark matter is a hypothetical form of matter that is thought to account for approximately 85% of the matter in the universe...[speaks the existence of dark matter existence is not proven, is not even part of the standard model!] [...] Its presence is implied in a variety of astrophysical observations, including gravitational effects that cannot be explained unless more matter is present than can be seen. […] The primary evidence for dark matter is that calculations show that many galaxies would fly apart instead of rotating, or would not have formed or move as they do, if they did not contain a large amount of unseen matter.[2] Other lines of evidence include observations in gravitational lensing,[3] from the cosmic microwave background, from astronomical observations of the observable universe's current structure, from the formation and evolution of galaxies, from mass location during galactic collisions,[4] and from the motion of galaxies within galaxy clusters. [so mismatch in gravitational effect with Einstein General Relativity is the only reason why people think there “must” be dark matter out there. Imagining dark matter would help to keep Einstein General Relativity correct in its current form, in other words it’s a HACK!] […] Although the existence of dark matter is generally accepted by the scientific community, some astrophysicists, intrigued by certain observations that do not fit the dark matter theory, argue for various modifications of the standard laws of general relativity, such as modified Newtonian dynamics, tensor–vector–scalar gravity, or entropic gravity. These models attempt to account for all observations without invoking supplemental non-baryonic matter. [means without the need for the hypothetical, non-observable dark matter. And because the standard model can not explain gravity, dark matter or modified gravity theory has nothing to do with the standard model as stated in my original comment]

maxander 8y ago
For what it's worth, I didn't downvote you- but you should realize the gap between what your Wikipedia source says and what you originally asserted. Yes, Wikipedia is right that the existence of dark matter isn't proven, and it's also true that there's no proven connection to the Standard Model; it's also true, as I said, that scientists are pretty sure that it does exist (the alternate theories are widely regarded as long shots.) And if it exists, this novel form of matter would need to be fit into the Standard Model somewhere, since that is intended to describe all forms of matter. Incidentally, I also think you're getting your history of science confused; the "cosmological constant" term Einstein used to make relativity consistent with his belief in a static, non-expanding universe was a "hack" (he himself wound up admitting it was unjustified.) But that's entirely unrelated to dark matter. Similar modern theories to the cosmological constant have been termed "dark energy," but the use of the word "dark" in both doesn't imply a real connection- it simply means that they each haven't been directly observed.