“Hubble tension”的版本间差异

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* ArXiv:2406.15548
* ArXiv:2406.15548
Given the abundance of precision cosmological data now avail�able, modifications to the standard ΛCDM that do not conflict with
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”
observations are surprisingly difficult to realize. The “least unlikely”
type of modification that is allowed (Knox & Millea 2020) increases
type of modification that is allowed (Knox & Millea 2020) increases
the expansion rate of the Universe before recombination. This modi�fication decreases the physical sound horizon measured by the CMB,
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
requiring an attendant decrease in the distance to the last scattering
that is obtained through an increase in 𝐻0. One possible mechanism
that is obtained through an increase in 𝐻0. One possible mechanism
for achieving this increased expansion at early times is “Early Dark
for achieving this increased expansion at early times is “Early Dark
Energy” (EDE), where a new cosmological energy source with an
Energy” (EDE), where a new cosmological energy source with an
equation of state similar to dark energy contributes ∼ 10% of the crit�ical density at its time of maximal contribution (𝑧 ∼ 3000; see Poulin
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).
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).