Can we be tricked into thinking W=-1

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SUMMARY

The discussion centers on the concept of dark energy, specifically the equation of state parameter w, and its implications in General Relativity (GR) and Brans-Dicke theory. It is established that dark energy models with w < -1, known as phantom energy, violate the dominant energy condition in GR, which poses a significant challenge to their validity. However, the paper referenced suggests that within the framework of Brans-Dicke theory, phantom energy can exist without violating this condition, offering a potential avenue for further exploration in cosmology.

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I'm always glad to read papers about dark energy. Dark energy can be described by its equation of state w. There's a model of dark energy with w<-1 called phantom energy. In the framework of GR, phantom energy violates the dominant energy condition. This seems a fatal blow to phantom energy. Generalizing, this paper says that in GR, all dark energy models with w<-1 violate the dominant energy condition.
But if you're a fan of phantom energy, this paper offers a hope: throw General Relativity to the trash bin, and worship a near relative called Brans-Dicke theory. This paper says that in the context of Brans-Dicke theory, phantom energy doesn't violate the dominant energy condition
 
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