Physics

Quantum Chromodynamics (QCD) is 50 years old. It was born in an atmosphere of skepticism toward the possibility that a local quantum field theory could ever describe the strong interaction. The experimental discoveries of the J/Psi and high-energy hadron jets, the establishment of asymptotic freedom, and the formulation of lattice QCD and effective field theories, among other facts, have changed the original skepticism about such a possibility. By now, the evidence that QCD is indeed the fundamental theory of strong interaction is overwhelming. Yet, we are far from understanding how it actually works. In this talk, I will focus on a couple of problems that challenge our understanding of QCD and get me out of bed in the morning.

The recent advancement of machine learning provides new opportunities for tackling challenges in quantum science, ranging from condensed matter physics, high energy physics to quantum information science. In this talk, I will first discuss a class of anti-symmetric wave functions based on neural network backflow,  which is efficient for simulating strongly-correlated lattice models and artificial quantum materials. Next, I will talk about recent progress of simulating continuum quantum field theories with neural quantum field state, and lattice gauge theories such as 2+1D quantum electrodynamics with finite density dynamical fermions using gauge symmetric neural networks. I will further discuss neural network representation based on positive-value-operator and phase space measurements for quantum dynamics simulations. Finally, I will present applications of machine learning in quantum control, quantum optimization and quantum machine learning.

Zoom link:  https://pitp.zoom.us/j/93834456412?pwd=R0hxdEpxanFFRnZmTHlqZTBXRi82QT09

In this colloquium, I will review how the notion of quantum error-correction has transformed our understanding of quantum gravity in the past decade.

Zoom link:  https://pitp.zoom.us/j/94349082665?pwd=OFdJdkpHU1NEcmlNeW5pWlg4WmNBZz09

Neste colóquio discorreremos sobre como conceitos da física são aplicados no mercado financeiro, enfatizando (i) o que mercado financeiro espera dos jovens ingressantes e (ii) como é a relação academia – mercado financeiro.

 I will present a novel behavior developed by scattering amplitudes in certain regions of the kinematic space, in which amplitudes factorize into 3 pieces without becoming singular. This is opposed to what happens in standard factorization or soft limits. We call this behavior a 3-split, and it is "semi-local" in nature. As 3-splits cannot be obtained from standard unitarity arguments, they represent a new phenomenon in QFT. I will introduce 3-splits in their simplest version, i.e. for the biadjoint scalar theory (which I will also introduce). If time allows, I will also comment on how 3-splits arise in other QFTs and how they lead to the discovery of more general theories.

Zoom link:  https://pitp.zoom.us/j/95575818902?pwd=V1RKYW9WMmZQNElVL2VyUGFGMFgxQT09

In this talk, I will first introduce the notion of operator delocalization, to be contrasted with the more conventional notion of operator growth, as a fundamental building block of operator scrambling.I will then use this machinery to analytically investigate the quantum charging advantage of a family of SYK quantum batteries. I will show that such an advantage ultimately relies on the operator delocalization properties of large size operators under the SYK dynamics, while it is unaffected by the presence or absence of operator growth.