Holography relates quantum many-body systems to gravitational theories. Quantum entanglement plays a key role to explain how the spacetime geometries in gravity emerge from quantum systems. A new class of holography can be found by introducing so called end-of-the-world branes and has been actively studied recently. Such holographic models…

 In this talk, I’ll survey some of the major open questions in particle physics and make the case that they can best be addressed by a qualitatively new type of particle accelerator: a high-energy muon collider.  Recent progress on long-standing accelerator and detector challenges make such a collider a compelling…

Intestinal organoids capture essential features of the intestinal epithelium such as crypt folding, spatial compartmentalization of different cell types, and cellular movements from crypt to villus. Each of these processes and their coordination in time and space requires patterned physical forces. I will present maps of the three-dimensional…

At the center of our Milky Way Galaxy lives a compact massive object called Sagittarius A* (Sgr A*) which is believed to be a black hole. Its mass, as inferred from the orbits of gravitationally bound stars as well as from direct images obtained by the Event Horizon Telescope, is 4 million solar masses. Gas accreting gravitationally on Sgr A*…

A new era in astrophysics was inaugurated with the 2015 discovery of gravitational waves from the collision of two black holes in data from the Laser Interferometer Gravitational-wave Observatory (LIGO). Since then, LIGO and its sister project Virgo have observed several more gravitational waves from the collision of black holes and neutron…

Liquid crystal elastomers are rubbery solids with liquid crystal mesogens incorporated into their polymer chains.  These solids combine the entropic elasticity of rubber with the orientational phase transitions of liquid crystals.  The deformation and orientational order are coupled, giving rise to a rich variety of phenomena…

The use of different perspectives on a problem is a very powerful principle in statistical physics, and has been especially important in mathematical physics. I will illustrate this theme with old and recent applications. These include the interpretation of QFTs at imaginary time as statistical fields, the relation of statistical fields to…

The bootstrap program leverages symmetry and positivity to carve out the space of consistent quantum theories. In this talk I will highlight some of its recent successes, ranging from the numerical solution of statistical models at criticality to universal constraints on quantum gravity.

Recording of Talk:…

Finding unconventional superconductors in proximity to various strongly correlated electronic phases has been a recurring theme in materials as diverse as heavy fermion compounds, cuprates, pnictides, and twisted bilayer graphene. The recent discovery of superconductivity in layered nickelates1 was motivated by looking for an analog of the…

There has been exciting recent progress in the study of the quantum nature of black holes through the use of certain exactly solvable models. This work shows how to realize, in concrete terms, various long-held expectations about quantum gravity, such as the transition from describing physics in terms of smooth spacetimes to a description in…

Cosmologists are proud of the standard cosmological model that has been developed to account for a wealth of disparate features of the Universe. The model requires, though, that we postulate the existence of some collisionless dark matter and also dark energy, a negative-pressure substance. The nature of both of these dark constituents is a…

The study of hyperuniform states of matter is an emerging multidisciplinary field, influencing and linking developments across the physical sciences, mathematics and biology. The hyperuniformity concept generalizes the traditional notion of long-range order to include not only all crystals and quasicrystals,…

The black hole information paradox — whether information escapes an evaporating black hole or not — remains one of the greatest unsolved mysteries of theoretical physics. The apparent conflict between validity of semiclassical gravity at low energies and unitarity of quantum mechanics has long been expected…

Remarkable experimental advances enabled creation of  highly tunable and controllable quantum systems of ultracold atoms, trapped ions, and superconducting quantum bits. These platforms proved to be uniquely suited for probing non-equilibrium properties of interacting quantum systems. Based on the intuition…

I will review the state of the field of gravitational wave astrophysics, framing the challenges, current observations, and future prospects within the context of the predictions of Einstein's theory of general relativity.

Recording of Prof. Pretorius' Talk: http:/…

Many modern materials feature a “Planckian metal”: a phase of electronic quantum matter without quasiparticle excitations, and relaxation in a time of order Planck's constant divided by the absolute temperature. The semiclassical theory of black holes predicts thermodynamic properties which are difficult to…

The discovery of compact object mergers by LIGO has opened up a new window into the Universe’s most exotic objects, neutron stars and black holes. Maximizing the scientific return of this new window requires connecting gravitational wave detections to the wealth of electromagnetic data on similar sources. I…

I will provide a brief overview of recent projects in my group where we identify new analytical and physical features of flows common to modern research questions. First, I will share some of our work (experimental and numerical) on fluid dynamics themes related to virus transmission by speech, which has…

String theory landscape of vacua point to new consistency conditions that a quantum gravitational system must satisfy.  There are only a small number of quantum field theories that satisfy these conditions and all the rest belong to the `Swampland' which cannot be consistently coupled to gravity.  In this talk I review some of these conditions…