Dark energy explained by a bias in the measurements. (arXiv:2007.11044v3 [astro-ph.CO] UPDATED)
<a href="http://arxiv.org/find/astro-ph/1/au:+Deledicque_V/0/1/0/all/0/1">Vincent Deledicque</a>
Typical cosmological models are based on the postulate that the universe is
homogeneous and isotropic in its spatial dimensions. Space is however not
perfectly homogeneous, and contains overdense regions in which matter is
concentrating, leaving other underdense regions of almost void. The evolution
of the scale factor of the universe has been established from measurements on
SNIa. Since such events occur in regions were matter is present, we may expect
that most of the SNIa that have been observed are located in overdense regions.
This means that the evolution of the scale factor has been established in a
biased manner, by considering only information coming from these overdense
regions, and excluding the one from the underdense regions. We develop in this
article a simple model to analyze the effect of this bias, and show that it
leads to the appearance of a new term in the Friedmann equation, which can
account for the apparent acceleration of the expansion of the universe. We
further show that this term presents the properties of a cosmological constant,
in particular that it tends to have a constant value, and that it is associated
to an apparent negative pressure. We also develop a general model to allow a
more quantitative comparison with the observations.
Typical cosmological models are based on the postulate that the universe is
homogeneous and isotropic in its spatial dimensions. Space is however not
perfectly homogeneous, and contains overdense regions in which matter is
concentrating, leaving other underdense regions of almost void. The evolution
of the scale factor of the universe has been established from measurements on
SNIa. Since such events occur in regions were matter is present, we may expect
that most of the SNIa that have been observed are located in overdense regions.
This means that the evolution of the scale factor has been established in a
biased manner, by considering only information coming from these overdense
regions, and excluding the one from the underdense regions. We develop in this
article a simple model to analyze the effect of this bias, and show that it
leads to the appearance of a new term in the Friedmann equation, which can
account for the apparent acceleration of the expansion of the universe. We
further show that this term presents the properties of a cosmological constant,
in particular that it tends to have a constant value, and that it is associated
to an apparent negative pressure. We also develop a general model to allow a
more quantitative comparison with the observations.
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