Physics

One of the best known open-source tools for studying numerical relativity is the Einstein Toolkit.  With it, you can simulate collisions of black holes and neutron stars, and study their horizons and gravitational waves. In this talk we learn more about what the Einstein Toolkit can do, how it works. An introductory, hands-on tutorial will follow.

Quantum complexity is a notion characterizing the universality of the entanglement arising from a quantum evolution. A universal evolution will result in a complex entanglement. At the same time, this also corresponds to small fluctuations and to unlearnability from the point of view of machine learning. All these aspects are connected to the different features of k-designs, which are under-samplings of the Hilbert space. 

We study the transition in complexity due to the doping of a quantum circuit by universal gates and show that the transition to complex entanglement can be obtained by just a single gate. 
These results are relevant for the notions of scrambling, quantum chaos, OTOCs and operator spreading.

We conjecture that the transition to 4−design, W-D and unlearnability are one and the same.

I will describe some connections between the Eigenstate Thermalization Hypothesis (ETH), the entanglement structure of generic excited eigenstates of chaotic quantum systems ("EE", arXiv:1906.04295), and the "bound on chaos" limiting the growth rate of the out-of-time-order four-point correlator in such systems ("OTOC", arXiv:1906.10808).

Higher spin symmetries are gauge symmetries sourced by massless particles with spin greater than two. When coupled with diffeomorphism, they give rise to higher spin gravity. After a review on higher spin gravity, I will discuss its holography and its embedding in the string theory. Finally I will talk about some applications of higher spin symmetry, both in string theory and in QFT. 

The core Python language is not particularly powerful or fast for numerical computing.  Fortunately, there is a large "numerical python" library, "numpy", that is a standard part of any Python-using scientist's toolkit.  I will present numpy, the associated "scientific python" library, "scipy", and the popular "matplotlib" plotting library.

Hypermassive neutron stars (HMNS) can be briefly formed after a binary neutron star merger and are likely to be highly deformed and strongly oscillating. These oscillations may be seen as modulation of the associated short gamma-ray burst and could provide observational evidence for the HMNS phase. I will discuss the prospects for their detection and the important physical information that can be gained by their observation.

 Python is a widely used programming language for scientific
computing, data analysis, and machine learning. This tutorial will
feature an introduction for those with little or no background.

In this talk I review some of what we have learned from string theory about the criteria one needs for a quantum theory to be able to consistently couple to quantum gravity (the landscape) as opposed to one that looks consistent but cannot be consistently coupled to gravity (the swampland).  Moreover, I review some of the cosmological implications of these conditions for our universe.