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Cosmology: a bird's eye view

Alan A. Coley·Sigbjorn Hervik·Woei Chet Lim
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Abstract

In this essay we discuss the difference in views of the Universe as seen by two different observers. While one of the observers follows a geodesic congruence defined by the geometry of the cosmological model, the other observer follows the fluid flow lines of a perfect fluid with a linear equation of state. We point out that the information these observers collect regarding the state of the Universe can be radically different; while one observes a non-inflating ever-expanding ever-lasting universe, the other observer can experience a dynamical behaviour reminiscent to that of quintessence or even that of a phantom cosmology leading to a 'big rip' singularity within finite time (but without the need for exotic forms of matter).

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Alan A. Coley, Sigbjorn Hervik, Woei Chet Lim. 2006-05-15. Cosmology: a bird's eye view. https://doi.org/10.1142/s0218271806009741

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