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I'm a graduate student in astronomy and I think it's extremely unlikely that dark energy or dark matter will go away. The concern of an "error cascade" was leg

I'm a graduate student in astronomy and I think it's extremely unlikely that dark energy or dark matter will go away. The concern of an "error cascade" was legitimate when these ideas were first proposed and many astronomers were skeptical of both dark matter and dark energy for long while. But over time there have been a number of independent lines of evidence pointing to the existence of both dark matter and dark energy. It's possible some comedy of errors could have lead to the spurious detection of dark matter or energy through one of these measurements, but very unlikely that it would be mimicked in other, independent measurements.

GravityWell 12y ago
Care to share some examples of dark energy evidence? If the evidence is a measurement of expansion, then it doesn't necessarily support the existence of dark energy.
- antognini 12y ago
  One of the other major pieces of evidence for the existence of dark energy is the observation of baryon acoustic oscillations. The basic idea is that as the universe was forming, there were concentrations of dark matter. Standing sound waves of photons and baryons (ordinary matter) formed around these concentrations. After decoupling, the photons streamed away, but the baryons remained and eventually formed galaxies. This results in a characteristic pattern seen on the sky, where there are clusters of galaxies observed, and then rings of galaxies around them. It is possible to calculate the physical size of these rings from first principles. Since you observe how big these rings appear on the sky, you can figure out how far away they are, and from this determine the expansion history of the universe.
  - vorg 12y ago
    > as the universe was forming, there were concentrations of dark matter. Standing sound waves of photons and baryons (ordinary matter) formed around these concentrations You make it sound like "dark matter" is normal matter and the "ordinary matter" is the abnormal stuff, since ordinary matter formed afterwards and has more complex interactions in that it supplements gravitation with electromagnetism and what not. And of course there's far more dark matter than ordinary.
- pdkl95 12y ago
  https://medium.com/starts-with-a-bang/five-reasons-we-think-dark-matter-exists-a122bd606ba8 https://medium.com/starts-with-a-bang/five-reasons-we-think-... While I'm not an astronomer, I think observations such as the the Bullet Cluster and the different position s for where the mass seems to be - including big changes in morphology, not just location - clearly indicates that something dark matter/energy-like must exist. The precise nature of this DM/DE is an a separate question.
- deleted 12y ago
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GravityWell 12y ago

Care to share some examples of dark energy evidence? If the evidence is a measurement of expansion, then it doesn't necessarily support the existence of dark energy.

antognini 12y ago
One of the other major pieces of evidence for the existence of dark energy is the observation of baryon acoustic oscillations. The basic idea is that as the universe was forming, there were concentrations of dark matter. Standing sound waves of photons and baryons (ordinary matter) formed around these concentrations. After decoupling, the photons streamed away, but the baryons remained and eventually formed galaxies. This results in a characteristic pattern seen on the sky, where there are clusters of galaxies observed, and then rings of galaxies around them. It is possible to calculate the physical size of these rings from first principles. Since you observe how big these rings appear on the sky, you can figure out how far away they are, and from this determine the expansion history of the universe.
- vorg 12y ago
  > as the universe was forming, there were concentrations of dark matter. Standing sound waves of photons and baryons (ordinary matter) formed around these concentrations You make it sound like "dark matter" is normal matter and the "ordinary matter" is the abnormal stuff, since ordinary matter formed afterwards and has more complex interactions in that it supplements gravitation with electromagnetism and what not. And of course there's far more dark matter than ordinary.
pdkl95 12y ago
https://medium.com/starts-with-a-bang/five-reasons-we-think-dark-matter-exists-a122bd606ba8 https://medium.com/starts-with-a-bang/five-reasons-we-think-... While I'm not an astronomer, I think observations such as the the Bullet Cluster and the different position s for where the mass seems to be - including big changes in morphology, not just location - clearly indicates that something dark matter/energy-like must exist. The precise nature of this DM/DE is an a separate question.
deleted 12y ago
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