This essay argues that gravity emerges from the running of physical constants with energy scale (called the Renormalization Group flow), and that this viewpoint can guide us to a viable theory of quantum gravity. It explains why this approach is not ruled out by "no go" theorems in the quantum gravity field, and what the existing paradigm for trying to develop a theory of quantum gravity may ge futile.
It's only ten pages long and more readable than many papers on the topic, so give it a read.
In this essay and utilizing the holographic Renormalization Group (RG) flow, we demonstrate how the effective action of a non-gravitating quantum field theory in the ultraviolet (UV) develops an Einstein-Hilbert term in the infrared (IR). That is, gravity is induced by the RG flow.
An inherent outcome of holography that plays a crucial role in our analysis is the RG flow of boundary conditions: the rigid Dirichlet conditions on the background metric in the UV become an admixture of Dirichlet and Neumann as we flow to the IR, thereby ``unfreezing'' the metric and transforming it from a non-dynamical background into a dynamical field.
This mechanism, which is a conceptually new addition to the standard Wilsonian RG flow, also provides the mechanism to evade the Weinberg-Witten no-go theorem.
Within the GR from RG picture outlined here, the search for a quantum theory of gravity by treating the metric as a fundamental field may be a hunt for a phantom -- akin to seeking the atomic structure of water by quantizing the equations of hydrodynamics.
M.M. Sheikh-Jabbari, V. Taghiloo, "GR from RG: Gravity Is Induced From Renormalization Group Flow In The Infrared" arXiv:2602.11806 (February 12, 2026) (Essay written for the Gravity Research Foundation 2026 Awards for Essays on Gravitation).
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