Comments about the News & Views article in Nature: Missing matter found in the cosmic web
Following is a discussion about this Article in Nature Vol 558 21 June 2018, by Taotao Feng
To read the article select: https://www.nature.com/articles/d41586-018-05432-2
- The text in italics is copied from the article
- Immediate followed by some comments
In the last paragraph I explain my own opinion.
Introduction
The article starts with the following sentence:
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We live in a dark Universe: just 5% of it consists of ordinary matter such as that found in atoms, whereas the rest is ‘dark’ matter and energy that cannot currently be detected directly.
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The fact that the word dark is written between ‘’ is remarkable. This implies a certain uncertainty or doubt.
Accordingly to: https://en.wikipedia.org/wiki/Dark_matter
the mainstream opinion holds:
In the standard Lambda-CDM model of cosmology, the total mass–energy of the universe contains 4.9% ordinary matter and energy, 26.8% dark matter and 68.3% of an unknown form of energy known as dark energy. Thus, dark matter constitutes 84.5% of total mass, while dark energy plus dark matter constitute 95.1% of total mass–energy content. Etc
The primary candidate for dark matter is some new kind of elementary particle that has not yet been discovered, in particular, WIMPs, or GIMPs.
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In the next sentence we read:
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However, observations of the nearby Universe suggest that up to 40% of this ordinary matter — which is made up primarily of particles known as baryons — is missing.
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This is interesting. The common accepted opinion was that the missing matter is non-baryonic and now this has changed to baryonic This means the complete opposite.
Next we read:
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Baryonic matter is thought to be distributed through the Universe like a cosmic web, and the missing baryons are predicted to be located in the filamentary structures that connect the web, and in intergalactic space
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It seems quite logical that there is a lot of baryonic matter in intergalactic space.
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By combining the X-ray data with measurements of the ultraviolet emissions from 1ES 1553+113, Nicastro et al. estimated the density of the baryons associated with the X-ray absorbing features, and found that they account for 9–40% of the cosmic baryon density — suggesting that these features are a substantial reservoir of the missing baryons.
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A more quantitative evaluation seems necessary.
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"Action at a distance"
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The now
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Reflection
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Created: 24 May 2018
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