Messengers from imaginary time: instantons and topological non-perturbative physics — from quantum mechanics to QCD and experimental searches
Tomas Sykora examines topological physics that perturbation theory cannot capture. Complex field configurations in path integrals include solitons, monopoles, domain walls, cosmic strings, sphalerons, baryon junctions and instantons; non-perturbative effects are central to confinement and hadron masses and spins. Starting with tunnelling in a double-well potential and imaginary time, the talk follows instantons into QCD, covering the theta vacuum, strong CP and axions, chiral symmetry breaking, topology and resurgence. It also considers whether a gluonic Y-shaped baryon junction carries baryon number instead of the valence quarks. The experimental discussion reviews instanton searches at HERA and the LHC, junction searches at RHIC, and prospective Electron-Ion Collider tests. No confirmed signal is claimed. Speaker: Tomas Sykora, Faculty of Mathematics and Physics, Charles University. Organized by Jiří Hejbal and Roman Lysák at FZU. Thursday 15 October 2026, 10:00–11:00 Europe/Prague (CEST). Attend at Dvořák Hall, FZU, Pod Vodárenskou věží 1, Prague, Czechia, or use the public Zoom link on the organizer’s event page.
Research Scientist or Senior Research Scientist — High-Energy QCD Theory Research Team (26-1024)
RIKEN is recruiting one indefinite-term Research Scientist or Senior Research Scientist for its High-Energy QCD Theory Research Team. Research spans lattice and perturbative QCD, the dynamical properties of strongly interacting matter, and connections to experimental data. The scientist will help establish the team and develop collaborations in Japan. Applicants need a relevant doctorate or equivalent research background and approximately seven years of postdoctoral experience. The position is based at Wako Campus, with an anticipated start after 1 February 2027. Applications must reach RIKEN by 30 September 2026; the official page specifies document uploads and applicant follow-up requirements.