J un 2 00 4 Football Shaped Extra Dimensions and the Absence of Self - Tuning
نویسنده
چکیده
There have been some recent claims that brane-worlds of co-dimension two in a 6D bulk with compact extra dimensions may lead to self-tuning of the effective 4D cosmological constant. Here we show that if a phase transition occurs on a flat brane, so as to change its tension, then the brane will not remain flat. In other words, there is really no self-tuning in such models, which can in fact be understood in four-dimensional terms and are therefore subject to Weinberg’s no-go theorem.
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Sidestepping the Cosmological Constant with Football-Shaped Extra Dimensions
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