“Hubble tension”的版本间差异
(创建页面,内容为“* ArXiv:2406.15548 Given the abundance of precision cosmological data now avail�able, modifications to the standard ΛCDM that do not conflict with observations ar…”) |
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* ArXiv:2406.15548 |
* ArXiv:2406.15548 |
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Given the abundance of precision cosmological data now |
Given the abundance of precision cosmological data now available, modifications to the standard ΛCDM that do not conflict with |
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observations are surprisingly difficult to realize. The “least unlikely” |
observations are surprisingly difficult to realize. The “least unlikely” |
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type of modification that is allowed (Knox & Millea 2020) increases |
type of modification that is allowed (Knox & Millea 2020) increases |
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the expansion rate of the Universe before recombination. This |
the expansion rate of the Universe before recombination. This modification decreases the physical sound horizon measured by the CMB, |
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requiring an attendant decrease in the distance to the last scattering |
requiring an attendant decrease in the distance to the last scattering |
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that is obtained through an increase in 𝐻0. One possible mechanism |
that is obtained through an increase in 𝐻0. One possible mechanism |
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for achieving this increased expansion at early times is “Early Dark |
for achieving this increased expansion at early times is “Early Dark |
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Energy” (EDE), where a new cosmological energy source with an |
Energy” (EDE), where a new cosmological energy source with an |
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equation of state similar to dark energy contributes ∼ 10% of the |
equation of state similar to dark energy contributes ∼ 10% of the critical density at its time of maximal contribution (𝑧 ∼ 3000; see Poulin |
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et al. 2023 for a recent review). |
et al. 2023 for a recent review). |
2024年6月25日 (二) 07:11的最新版本
- ArXiv:2406.15548
Given the abundance of precision cosmological data now available, modifications to the standard ΛCDM that do not conflict with observations are surprisingly difficult to realize. The “least unlikely” type of modification that is allowed (Knox & Millea 2020) increases the expansion rate of the Universe before recombination. This modification decreases the physical sound horizon measured by the CMB, requiring an attendant decrease in the distance to the last scattering that is obtained through an increase in 𝐻0. One possible mechanism for achieving this increased expansion at early times is “Early Dark Energy” (EDE), where a new cosmological energy source with an equation of state similar to dark energy contributes ∼ 10% of the critical density at its time of maximal contribution (𝑧 ∼ 3000; see Poulin et al. 2023 for a recent review).