Efimov Physics and Connections to Nuclear Physics

Physical systems characterized by a shallow two-body bound or virtual state are governed at large distances by continuous scale invariance, which is broken into discrete scale invariance when three or more particles come into play. This symmetry induces a universal behavior for different systems that is independent of the details of the underlying interaction and rooted in the smallness of the ratio ℓ[Formula: see text] a B ≪ 1, where the length a B is associated with the binding energy of the two-body system [Formula: see text], and ℓ is the natural length given by the interaction range. Efimov physics refers to this universal behavior, which is often hidden by the onset of system-specific nonuniversal effects. In this review, we identify universal properties by providing an explicit link of physical systems to their unitary limit, in which a B → ∞, and we show that nuclear systems belong to this class of universality. Expected final online publication date for the Annual Review of Nuclear and Particle Science, Volume 71 is September 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Efimov physics in curved spacetime: Field fluctuations and exotic matter

Several experimental detections have demonstrated the existence of Borromean states predicted by Vitaly Efimov within a nuclear physics context, that is, trimers bound despite the absence of bound states of any of the two-body subsystems. I show that novel Efimov Physics is expected in gravitationally polarizable nonbaryonic dark matter beyond the Standard Model with van der Waals-like forces driven by quantum gravitational fluctuations. I also discuss ground and space-based tests of spacetime curvature effects on weakly bound, highly diffuse quantum three-body systems with standard electrodynamical van der Waals forces. Finally, I consider exotic gravitational quantum matter from higher-order Brunnian structures and analogies with classical systems, already proven in three-stranded DNA, driven by the stochastic gravitational wave background.