We may be in a bubble:
Earth may be trapped in an abnormal bubble of space-time that is particularly void of matter.
Scientists say this condition could account for the apparent acceleration of the universe’s expansion, for which dark energy currently is the leading explanation.
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“If we lived in a very large under-density, then the space-time itself wouldn’t be accelerating,” said researcher Timothy Clifton of Oxford University in England. “It would just be that the observations, if interpreted in the usual way, would look like they were.”
One reason why this theory still isn’t widely accepted:
One problem with the void idea, though, is that it negates a principle that has reined in astronomy for more than 450 years: namely, that our place in the universe isn’t special.
When Nicholas Copernicus argued that it made much more sense for the Earth to be revolving around the sun than vice versa, it revolutionized science.
Since then, most theories have to pass the Copernican test. If they require our planet to be unique, or our position to be exalted, the ideas often seem unlikely.
This is obliquely tied to the problem of the apparent un-arbitraryness of our universe: a key scientific and philosophical problem for the 21st Century – why is it that the universe seems to be conveniently set up for life.