Topic: effective field theory

Davide Germani discusses how established field-theory techniques help interpret precise ATLAS and CMS measurements of heavy-quark systems. The first case concerns top–antitop states near their production threshold, drawing on recent calculations by Paolo Nason and collaborators. Topics include threshold resummation, nonperturbative QCD corrections, and the way the top quark’s short lifetime controls the formation and decay of quasi-bound states at collider energies. The second case examines whether X(3872) is a compact exotic hadron or a weakly bound neutral D-meson molecule. A comparison of t

Precision measurements involving atoms and nuclei address dark matter, neutrino masses and leptonic CP violation. This talk explains how effective field theory improves predictions for neutrino–nucleus scattering, coherent muon conversion and beta decays. Superallowed beta decay provides an example in which multi-loop electromagnetic corrections matter for first-row CKM unitarity tests.

Vijay Balasubramanian connects quantum chaos with the complexity of time evolution. One approach bounds the smallest circuit needed to simulate physical dynamics; another measures how quickly and ergodically a state explores its accessible Hilbert space. Examples from spin chains, billiards, many-body systems and random matrices distinguish chaotic and integrable behaviour. Applications address geometric conjectures for complexity in quantum gravity and possible failure of effective field theory near spacelike singularities.