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Limitations in using luminosity distance to determine the equation of state of the universe

Irit Maor·Ram Brustein·Paul J. Steinhardt
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Abstract

Supernova searches have been been suggested as a method for determining precisely the current value and time variation of the equation of state, $w$, of the dark energy component responsible for the accelerated expansion of the Universe. We show that the method is fundamentally limited by the fact that luminosity dista nce depends on $w$ through a multiple integral relation that smears out information about $w$ and its time variatio n. The effect degrades the resolution of $w$ that can be obtained from current d ata.

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Irit Maor, Ram Brustein, Paul J. Steinhardt. 2001-05-03. Limitations in using luminosity distance to determine the equation of state of the universe. https://doi.org/10.1103/physrevlett.86.6

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