Seminar by Professor Neil Bourne will be held in the Ray Dolby Auditorium in the Physics Department from 16:00 on May 19th.

When plasma comes to earth

Quantum, electron‑degenerate matter usually belongs in white dwarfs and fusion capsules, but states within a shock front can connect that physics to ordinary solids. Solids under extreme loading organise themselves around the shock front, not the phase diagram. This talk shows that metals, polymers, silicates and ionic crystals share a common hierarchy of limits: a weak‑shock cut‑off where defect‑mediated shear is exhausted, a lattice‑collapse band, and an electron‑degenerate branch at the highest pressures. ​ When stresses are normalised by the weak‑shock limit, these very different systems fall on a single strong‑shock trajectory over many decades in strain rate, following a near‑universal fourth‑power law for the shock‑front strain rate. This mechanics‑to‑quantum hierarchy leads to a dynamic equation of state that couples thermodynamics to front kinetics and turns microstructure and processing into genuine design knobs for response in extremes.