We are trying to develop a fundamental theory for Quantum Effects in Strong, Classical Potentials and trying to answer these questions:

1. When should we begin to consider Quantum Effects in Strong Classical Potentials?

2. How do we describe them? (Developing a Non-perturbative, Dynamic Quantum Field Theory)

Is a new theory of matter and light needed at the highest energies or the highest intensities?
Matter and radiation in the laboratory appear to be extraordinarily well described by the laws of quantum mechanics, electromagnetism, and their unification as quantum electrodynamics. However the universe presents us with places and objects, such as neutron stars and the sources of gamma ray bursts, where the conditions are far more extreme than anything we can reproduce on Earth that can be used to test these basic theories.

Sufficiently strong electromagnetic fields allow fundamentally new quantum processes: electron-positron pairs are created from vacuum; photons split, merge, and convert into pairs; new degrees of freedom may emerge due to breaking the classical conformal symmetry. These are the QED equivalents of Hawking radiation and quark-gluon plasma formation, that are important, hotly discussed questions in how quantum theory and gravity work together and how the theory of strong interactions (QCD) works at long wavelength.

Using PW-class lasers such as the TPW, we can access related nonperturbative effects, such as high-energy photon emission and pair bremsstrahlung from an accelerated electron, that occur at lower field strength. To predict them, we need to be able to separate classical radiation and plasma dynamics from the underlying quantum event. To this end, we are developing the first systematic theory of quantum electrodynamic processes in relativistic laser fields.

This theory and laser experiments offer a unique opportunity to test quantum dynamics at the newly-opened high intensity frontier.