The Stochastic Schwinger Effect

by Azadeh Maleknejad (Swansea University (GB))

Wednesday Jun 10, 2026, 11:30 AM → 12:30 PM Europe/Zurich

4/2-011 - TH common room (CERN)

Particle production from background fields is one of the sharpest manifestations of quantum field theory in extreme environments. I will begin with a brief overview of particle creation in external fields, from the classical coherent Schwinger effect to its modern generalizations. I will then introduce a new mechanism that we call the stochastic Schwinger effect, motivated by the fact that realistic gauge fields in the early Universe and high-energy astrophysical environments are often transient and statistically fluctuating. Unlike the static Schwinger effect, where particle production is intrinsically non-perturbative, here the stochastic spectrum opens a perturbative channel for vacuum decay. Using the effective action formalism, we derive analytical results for the decay rate and particle number density for both scalar and fermionic fields. I will conclude by discussing possible implications for the early Universe, within and beyond the Standard Model, and by placing this effect in a broader theoretical perspective alongside its gravitational analogue: particle production by stochastic cosmic perturbations, or gravitational-wave freeze-in. Together, these mechanisms point toward a wider paradigm in which fluctuating gauge and gravitational backgrounds can leave behind quantum relics of the primordial Universe.