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I mean, we need to have a convenient term for a phenomenon even if we don't understand it. What's the alternative? "The unnamed phenomenon were some astronomic

I mean, we need to have a convenient term for a phenomenon even if we don't understand it. What's the alternative? "The unnamed phenomenon were some astronomic bodies behave as though a vast quantity of matter were affecting them but that matter can't be otherwise detected or identified"? In medicine, they often call it a "syndrome". A collection of symptoms that together form a known pattern that is often closely associated with a disease or disorder but has no understood cause or origin (although some syndromes continue to be called that after they are better understood). How do you think we arrived at terms like "planets"? We noticed that some stars in the sky moved around while the rest didn't, and we called them "wandering stars". We still call them "atoms" even though that word means "indivisible". Weather is full of such names: rain, thunder, lightning, wind, morning glory, dew, tornado, rainbow, etc. All these words for material phenomenon existed long before we knew how they worked. So what's wrong with "dark matter" as a name?

colordrops 5y ago
I didn't read a negative judgment of the term in the grandparent comment, just an observation.
- da_chicken 5y ago
  Yes, and I'm challenging that observation. "Making an observation" doesn't mean you're not subject to criticism or questioning.
  - burnished 5y ago
    You haven't meaningfully challenged anything they said, though. Your thing was an odd rant about the need to name things (not a hot take), and theirs seemed more focused, well >>That is, an interrim scientific theory that will eventually be completely replaced by revisions of our physics.
    - deleted 5y ago
      [deleted]
  - colordrops 5y ago
    But you were reading criticism of the naming in the original comment, which wasn't there.
dnautics 5y ago
> So what's wrong with "dark matter" as a name? it encodes a normative, biased prejudgement about what we think explains the syndrome.
- tracedddd 5y ago
  What would you prefer the concept be called?
  - dnautics 5y ago
    Gravitational anomalies, gravitational discrepancy, unexplained gravity effect? Hell, dark gravity, if you want. Until the point where the observations are multimodal. Then I'd be more comfortable assigning provisionally normative names. Till then it should probably explicitly reference the fact that all observations are gravitational in nature.
    - slowmovintarget 5y ago
      Dark matter works just fine. It needs to be "matter" in the cosmological sense [1] because of the ratio of protons and neutrons to photons produced during Big Bang nucleosythesis. We know the ratio of the number of protons to number of photons. We know the number of photons in the universe (most of them are in the CMB), and we therefore know the number of protons. That means we know the amount of "normal" matter in the universe, and it is far less than the total amount of matter in the universe (that must have survived from baryogenesis). This requires there to be "dark matter" in the universe. The other effects like galaxy formation and stellar motion in galaxies are just things that might be caused by dark matter (though that's come into doubt). Sean Carroll discusses it here: https://youtu.be/tZQadPmTd84?t=4642 https://youtu.be/tZQadPmTd84?t=4642 [1] "Matter" in the cosmological sense is "stuff" that moves slower than the speed of light, as opposed to "energy" which moves at the speed of light.
- karmakaze 5y ago
  Exactly, the fact that it's a phenomenon gets lost--all we have to do is find the missing mass (X-Y problem) that's causing the gravitational effects.
MR4D 5y ago
Ether. X-rays. Black hole. Dark matter. I think it’s going to stick as a name even when the details have been largely worked out, especially considering the other examples I listed.
ASalazarMX 5y ago
> The unnamed phenomenon were some astronomic bodies behave as though a vast quantity of matter were affecting them but that matter can't be otherwise detected or identified" How about "missing matter"? To non-astronomers, dark matter sounds like it has already been found and it doesn't emit light.
- tcskeptic 5y ago
  It's not missing though, is it? It has the characteristic of having effects of mass but not being otherwise observable.
  - ASalazarMX 5y ago
    Other comments have suggested better names, based on the fact that we don't even know for sure that it's matter, just that gravity at large scale doesn't behave like it should.
- wumpus 5y ago
  If you say "missing matter", the thing most physicists think of first is probably missing anti-matter, and then missing baryons. Not dark matter. It's a bit late to suggest new nomenclature for something that's been around for many decades.
superduperycomb 5y ago
Those are all example of observable phenomena. Dark matter is an inference made by inconsistencies with theory. I think they’re vastly different because it overstates the certainty. Maybe I’m splitting hairs
fifticon 5y ago
No worry, I did not intend any criticism of 'dark matter'. I understand it as a placeholder concept for 'something we know amazingly little about, except that it appears to be in conflict with the naive version of our observations'. It reminds me of the very complex ways humans calculated the planetary motions, when they believed the sun revolved around the earth - once the proper relation was understood, a comparatively simpler model sufficed. As I understand it, we have plenty of guesses at what dark matter could be, including quantum particles that emit no energy we (currently) can observe. I believe the original theory of ether also sufficed in its time, until we had enough observations that contradicted that model. I'm not saying dark matter is wrong in any way, but it appears to me, it's a place-holder concept for until knowing what is _really_ going on, like 'planet X'.

colordrops 5y ago

I didn't read a negative judgment of the term in the grandparent comment, just an observation.

da_chicken 5y ago
Yes, and I'm challenging that observation. "Making an observation" doesn't mean you're not subject to criticism or questioning.
- burnished 5y ago
  You haven't meaningfully challenged anything they said, though. Your thing was an odd rant about the need to name things (not a hot take), and theirs seemed more focused, well >>That is, an interrim scientific theory that will eventually be completely replaced by revisions of our physics.
  - deleted 5y ago
    [deleted]
- colordrops 5y ago
  But you were reading criticism of the naming in the original comment, which wasn't there.

dnautics 5y ago

> So what's wrong with "dark matter" as a name? it encodes a normative, biased prejudgement about what we think explains the syndrome.

tracedddd 5y ago
What would you prefer the concept be called?
- dnautics 5y ago
  Gravitational anomalies, gravitational discrepancy, unexplained gravity effect? Hell, dark gravity, if you want. Until the point where the observations are multimodal. Then I'd be more comfortable assigning provisionally normative names. Till then it should probably explicitly reference the fact that all observations are gravitational in nature.
  - slowmovintarget 5y ago
    Dark matter works just fine. It needs to be "matter" in the cosmological sense [1] because of the ratio of protons and neutrons to photons produced during Big Bang nucleosythesis. We know the ratio of the number of protons to number of photons. We know the number of photons in the universe (most of them are in the CMB), and we therefore know the number of protons. That means we know the amount of "normal" matter in the universe, and it is far less than the total amount of matter in the universe (that must have survived from baryogenesis). This requires there to be "dark matter" in the universe. The other effects like galaxy formation and stellar motion in galaxies are just things that might be caused by dark matter (though that's come into doubt). Sean Carroll discusses it here: https://youtu.be/tZQadPmTd84?t=4642 https://youtu.be/tZQadPmTd84?t=4642 [1] "Matter" in the cosmological sense is "stuff" that moves slower than the speed of light, as opposed to "energy" which moves at the speed of light.
karmakaze 5y ago
Exactly, the fact that it's a phenomenon gets lost--all we have to do is find the missing mass (X-Y problem) that's causing the gravitational effects.

MR4D 5y ago

Ether. X-rays. Black hole. Dark matter. I think it’s going to stick as a name even when the details have been largely worked out, especially considering the other examples I listed.

ASalazarMX 5y ago

> The unnamed phenomenon were some astronomic bodies behave as though a vast quantity of matter were affecting them but that matter can't be otherwise detected or identified" How about "missing matter"? To non-astronomers, dark matter sounds like it has already been found and it doesn't emit light.

tcskeptic 5y ago
It's not missing though, is it? It has the characteristic of having effects of mass but not being otherwise observable.
- ASalazarMX 5y ago
  Other comments have suggested better names, based on the fact that we don't even know for sure that it's matter, just that gravity at large scale doesn't behave like it should.
wumpus 5y ago
If you say "missing matter", the thing most physicists think of first is probably missing anti-matter, and then missing baryons. Not dark matter. It's a bit late to suggest new nomenclature for something that's been around for many decades.

superduperycomb 5y ago

Those are all example of observable phenomena. Dark matter is an inference made by inconsistencies with theory. I think they’re vastly different because it overstates the certainty. Maybe I’m splitting hairs

fifticon 5y ago

No worry, I did not intend any criticism of 'dark matter'. I understand it as a placeholder concept for 'something we know amazingly little about, except that it appears to be in conflict with the naive version of our observations'. It reminds me of the very complex ways humans calculated the planetary motions, when they believed the sun revolved around the earth - once the proper relation was understood, a comparatively simpler model sufficed. As I understand it, we have plenty of guesses at what dark matter could be, including quantum particles that emit no energy we (currently) can observe. I believe the original theory of ether also sufficed in its time, until we had enough observations that contradicted that model. I'm not saying dark matter is wrong in any way, but it appears to me, it's a place-holder concept for until knowing what is _really_ going on, like 'planet X'.