Four-derivative interactions in asymptotically safe gravity
نویسندگان
چکیده
We summarize recent progress in understanding the role of higher-derivative terms in the asymptotic safety scenario of gravity. Extending previous computations based on the functional renormalization group approach by including a Weyl-squared term in the ansatz for the effective action, further evidence for the existence of a non-Gaussian fixed point is found. The fixed point also persists upon including a minimally coupled free scalar field, providing an explicit example of perturbative counterterms being non-hazardous for asymptotic safety.
منابع مشابه
Asymptotic Safety in Higher-Derivative Gravity
We study the non-perturbative renormalization group flow of higher-derivative gravity employing functional renormalization group techniques. The non-perturbative contributions to the β-functions shift the known perturbative ultraviolet fixed point into a non-trivial fixed point with three UV-attractive and one UV-repulsive eigendirections, consistent with the asymptotic safety conjecture of gra...
متن کاملدستهای از جوابهای دقیق گرانش با مشتقات بالاتر در چهار بعد
In this paper we consider the action of higher derivative gravity up to the second order terms in the scalars made from the Ricci scalar, Ricci and Riemann tensors. We use the Bach- Lanczos identity of the Weyl tensor in four dimensions and show that the solutions of 4-dimensional Einstein equations with cosmological constant term in vacuum, which are known as Einstein metrics, satisfy the fie...
متن کاملNon-supersymmetric Attractors in Born-Infeld Black Holes with a Cosmological Constant
We investigate the attractor mechanism for spherically symmetric extremal black holes in Einstein-Born-Infeld-dilaton theory of gravity in four-dimensions, in the presence of a cosmological constant. We look for solutions analytic near the horizon by using perturbation method. It is shown that the values of the scalar fields at the horizon are only dependent on the charges carried by the black ...
متن کاملBouncing Universes in String-inspired Gravity
We consider the effects on cosmology of higher-derivative modifications of (effective) gravity that make it asymptotically free without introducing ghosts. The weakening of gravity at short distances allows pressure to prevent the singularity, producing a solution with contraction preceding expansion.
متن کاملAn asymptotic-safety mechanism for chiral Yukawa systems
We introduce Weinberg’s idea of asymptotic safety and pave the way towards an asymptotically safe chiral Yukawa system with a U(NL)L⊗U(1)R symmetry in a leading-order derivative expansion using nonperturbative functional RG equations. As a toy model sharing important features with the standard model we explicitely discuss NL = 10 for which we find a non-Gaußian fixed point and compute its criti...
متن کامل