Whenexposedtointenseelectromagneticfields,thequantumvacuumisexpectedtoexhibitpropertiesofapolarizablemediumakintoaweaklynonlineardielectricmaterial.Variousschemeshavebeenproposedtomeasuresuchvacuumpolarizationeffectsusingacombinationofhigh-powerlasers.Motivatedbyseveralplannedexperiments,weprovideanoverviewofexperimentalsignaturesthathavebeensuggestedtoconfirmthispredictionofquantumelectrodynamicsofrealphoton–photonscattering.
