Here are a list of our upcoming seminar or journal club programs : 

Jets provide one of the primary probes of the quark-gluon plasma produced in ultrarelativistic heavy ion collisions. In this talk, we will explore quantum technologies as a promising alternative theoretical laboratory to simulate jet evolution in QCD matter, to overcome inherent technical difficulties in classical calculations. Based on the light-front Hamiltonian formalism, we construct a digital quantum circuit that tracks the evolution of a multi-particle jet probe in the presence of a medium described as a stochastic color field. From the simulation, we observe and study the momentum broadening, medium-induced gluon emission, von-Neumann entropy of the jet. We will also discuss various ongoing endeavors for a fully quantum description of the jet in a medium, as well as novel applications to study other areas of heavy ion collisions.

In high-energy hadronic collisions, heavy quarks (charm and beauty), due to their large masses (mq >> ΛQCD), are mostly produced in the hard QCD processes during the early stages of the collisions. Their production is well understood by perturbative quantum chromodynamics (pQCD) calculations. Jets, which are collimated sprays of particles produced by the hard-scattered partons, have been a crucial observable in high-energy particle physics as they provide direct access to the kinematics of the parton initiating the shower. The properties of partonic fragmentation in QCD depend on the flavors of the partons involved in the 1→2 splitting processes that drive parton showers. These dependencies arise from the differences in the Casimir factors of quarks and gluons, as well as the mass of heavy quarks (dead-cone effect). To explore these flavor dependencies, we use heavy-flavor tagged jets as an experimental tool, particularly at low and intermediate transverse momenta where mass effects are significant. In this talk, I will present the recent results on charm-tagged (fully reconstructed D0 -mesons) jets by the ALICE experiment at the Large Hadron Collider (LHC). These results include the measurements of the fragmentation function of jets containing fully reconstructed D0-mesons, first direct measurement of the dead-cone effect at colliders, using the comparison of Lund planes of charm-tagged jets and inclusive jets, and the first measurement of jet generalized angularity which can be tuned in their sensitivity to mass and Casimir effects. Comparisons to flavor-untagged jet sample will probe both the flavor dependencies due to the mass of the charm quark, as well as the high purity quark nature of the D0-tagged jet sample. Further comparisons to different MC generators will access the role of these flavor dependencies in different parton shower prescriptions.

In this talk, I will cover the work in progress to accelerate the MadGraph5 program to get a code that meet the experimental needs for HL-LHC. This will cover two big topic: theoretical pile-up (i.e. data parralelism) and machine learning. Together those developments will break the boundary of what is possible to simulate today. If you do not know the detail of data-parralelism and the detail of machine learning, then this talk is made for you. You will learn during the talk the difference and similarity between a CPU and a GPU, you will learn how a Monte-Carlo integration works and how machine learning is crucial to have fast and efficient event generation.

In this talk, we introduce a new unbinned two sample test statistic sensitive to CP violation utilizing the optimal transport plan associated with the Wasserstein (earth mover's) distance. The efficacy of the test statistic is shown via two examples of CP asymmetric distributions with varying sample sizes: the Dalitz distributions of $B^0 \to K^+\pi^-\pi^0$ and of $D^0\to \pi^+\pi^-\pi^0$ decays. The windowed version of the Wasserstein distance test statistic is shown to have comparable sensitivity to CP violation as the commonly used energy test statistic, but also retains information about the localized distributions of CP asymmetry over the Dalitz plot. For large statistic datasets we introduce two modified Wasserstein distance based test statistics -- the binned and the sliced Wasserstein distance statistics, which show comparable sensitivity to CP violation, but improved computing time and memory scalings. Finally, general extensions and applications of the introduced statistics are discussed.

Hadronization is an important open problem in high energy physics and it is difficult to solve because of its non-perturbative and non-equilibrium character. I will discuss this problem in terms of reduced models in two spacetime dimensions for QCD strings with an emphasis on the dynamics of quantum entanglement. I will also outline how some of the relevant physics mechanisms could be investigated further using quantum simulation.

Recent results for high multiplicity pp and p-Pb collisions at the LHC have revealed that they exhibit heavy-ion-like behaviors. To understand the origin(s) of these unexpected phenomena, event shape observables such as transverse spherocity and the relative transverse activity classifier can be exploited as powerful tools to disentangle soft (non-perturbative) and hard (perturbative) particle production. After its successful implementation in small collision systems, transverse spherocity holds an opportunity to reveal more about theparticle production in heavy-ion collisions as well. In the absence of any experimental exploration in this direction at the LHC yet, we suggest an ML-based regression method to estimate event shape observables along with the impact parameter of a heavy-ion collision.

Heavy-ion collisions produce far-from-equilibrium QCD matter which rapidly becomes a hydrodynamic medium. In this talk, I discuss how jets are shaped by the initial stage of heavy-ion collisions. Most importantly, I show that anisotropic momentum broadening of jets at early times leads to net spin in emitted gluons. This means that there is net spin polarization of jet partons which is constant at all energy scales. I furthermore discuss jet broadening in the later hydrodynamic stage. Using tools of non-equilibrium field theory, I show that momentum broadening is substantially reduced at lower transverse momenta compared with a medium in thermal equilibrium.

In the course of the past 15 years there have been an enormous progress in understanding quantum underpinnings of gravity using the language of quantum information processing. I will discuss new ideas and progress that emerged on three fronts: entanglement entropy and surfaces in gravity, complexity and volumes in gravity and the Hawking's information paradox.

 The fast development of quantum technologies over the last decades has offered a glimpse to a future where the quantum properties of multi-particle systems might be fully understood. So far, quantum computing has seen ample application in areas such as quantum chemistry or condensed matter, but its usage in high energy physics is still in its infancy. In this talk, I will first provide a short introduction to elements of digital quantum computing and its application to real time simulation of physical systems. I will then proceed to discuss scattering at high energies in the S-matrix approach using a quantum computer. Finally, I will detail how jet evolution in a dense medium can be studied using a small scale quantum computer and what can be learned from these types of simulations.