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Asymptotic safety is a scenario in which gravity is not emergent, ie. degrees of freedom at low energy are sufficient for a complete description at high energy.
Calculations from Bern and colleagues have been showing that N=8 supergravity is less divergent than previously suspected. A new paper from Kallosh http://arxiv.org/abs/1009.1135 states "30 years ago N=8 supergravity in four dimensions was suspected to be UV divergent at higher loop orders. The suspicion was based on a construction of an infinite set of superinvariants [6, 7] in a Lorentz covariant on shell superspace geometry with 32 Grassmann coordinates. These counterterms were viewed as candidates for UV divergences. 2 years ago one of the accusers proposed to restore the presumption of innocence ... Thus, in this paper N=8 d = 4 supergravity is acquitted from the previous accusation in [6, 7] and is predicted to be UV finite if there are no anomalies violating the equivalence theorem for physical observables."
What might the implications of this be for Asymptotic Safety, and for string theory?
Calculations from Bern and colleagues have been showing that N=8 supergravity is less divergent than previously suspected. A new paper from Kallosh http://arxiv.org/abs/1009.1135 states "30 years ago N=8 supergravity in four dimensions was suspected to be UV divergent at higher loop orders. The suspicion was based on a construction of an infinite set of superinvariants [6, 7] in a Lorentz covariant on shell superspace geometry with 32 Grassmann coordinates. These counterterms were viewed as candidates for UV divergences. 2 years ago one of the accusers proposed to restore the presumption of innocence ... Thus, in this paper N=8 d = 4 supergravity is acquitted from the previous accusation in [6, 7] and is predicted to be UV finite if there are no anomalies violating the equivalence theorem for physical observables."
What might the implications of this be for Asymptotic Safety, and for string theory?