Present and future ofCosmoLattice.

We discuss the present state and planned updates ofCosmoLattice, a cutting-edge code for lattice simulations of non-linear dynamics of scalar-gauge field theories in an expanding background. We first review the current capabilities of the code, including the simulation of interacting singlet scalars and of Abelian and non-Abelian scalar-gauge theories. We also comment on new features recently implemented, such as the simulation of gravitational waves from scalar and gauge fields. Secondly, we discuss new extensions ofCosmoLatticethat we plan to release publicly. We comment on new physics modules, which include axion-gauge interactionsϕFF~, non-minimal gravitational couplingsϕ2R, creation and evolution of cosmic-defect networks, and magnetohydrodynamics. We also discuss new technical features, including evolvers for non-canonical interactions, arbitrary initial conditions, simulations in 2+1 dimensions, and higher-accuracy spatial derivatives.

Real-Time Nonperturbative Dynamics of Jet Production in Schwinger Model: Quantum Entanglement and Vacuum Modification.

The production of jets should allow testing the real-time response of the QCD vacuum disturbed by the propagation of high-momentum color charges. Addressing this problem theoretically requires a real-time, nonperturbative method. It is well known that the Schwinger model [QED in (1+1) dimensions] shares many common properties with QCD, including confinement, chiral symmetry breaking, and the existence of vacuum fermion condensate. As a step in developing such an approach, we report here on fully quantum simulations of a massive Schwinger model coupled to external sources representing quark and antiquark jets as produced in e^{+}e^{-} annihilation. We study, for the first time, the modification of the vacuum chiral condensate by the propagating jets and the quantum entanglement between the fragmenting jets. Our results indicate strong entanglement between the fragmentation products of the two jets at rapidity separations Δη≤2, which can potentially exist also in QCD and can be studied in experiments.

Open-boundary conditions in the deconfined phase.

In this work, we consider open-boundary conditions at high temperatures, as they can potentially be of help to measure the topological susceptibility. In particular, we measure the extent of the boundary effects at T = 1.5 T c and T = 2.7 T c . In the first case, it is larger than at T = 0 while we find it to be smaller in the second case. The length of this "boundary zone" is controlled by the screening masses. We use this fact to measure the scalar and pseudo-scalar screening masses at these two temperatures. We observe a mass gap at T = 1.5 T c but not at T = 2.7 T c . Finally, we use our pseudo-scalar channel analysis to estimate the topological susceptibility. The results at T = 1.5 T c are in good agreement with the literature. At T = 2.7 T c , they appear to suffer from topological freezing, which prevents us from providing a precise determination of the topological susceptibility.