Abstracts/Topics:

Speaker (Affiliation): Nima Arkani-Hamed (Institute for Advanced Study, Princeton)

Title: Spacetime, Quantum Mechanics and Positive Geometry at Infinity

Abstract: TBA

Speaker (Affiliation): Alessandra Buonanno (Max Planck Institute for Gravitational Physics)

Title: The Making of High-Precision Gravitational Waves to Explore the Dark Universe

Abstract: The solution of the two-body problem in General Relativity has been crucial in observing gravitational waves from binary systems composed of black holes and neutron stars, and inferring their astrophysical, cosmological and gravitational properties. I will review the theoretical groundwork that has enabled these observations, and discuss recent theoretical advances aimed at predicting highly accurate waveform models for future detectors on the ground and in space. Finally, I will highlight some interesting observational findings obtained recently by the LIGO and Virgo detectors.

Speaker (Affiliation): Zohreh Davoudi (University of Maryland)

Title: Toward quantum simulation of systems of relevance to nuclear and particle physics

Abstract: A vibrant program has formed in recent years in various scientific disciplines to take advantage of near-term and future quantum-simulation and quantum-computing hardware to study complex quantum many-body systems, building upon the vision of Richard Feynman for quantum simulation. Such activities have recently started in nuclear and particle physics, hoping to bring new and powerful experimental and computational tools to eventually address a range of challenging problems in strongly interacting quantum field theories and nuclear many-body systems. In this talk, I first motivate the need for quantum simulation in nuclear physics by showcasing some of the state of the art in our classical simulations and discussing the existing challenges to move ahead. I will then review a number of important developments in quantum simulation, including proposals for simulating strongly interacting field theories with the ultimate goal of studying strong dynamics of quarks and gluons, and of nucleons. Some of the requirements for hardware technologies that are expected to enable both the analog simulations and the digital quantum computations of these problems will be enumerated, and an experiment-theory co-development program will be motivated with an emphasis on trapped-ion platforms.

Speaker (Affiliation): George Efstathiou (Kavli Institute for Cosmology, Cambridge)

Title: The Hubble Tension

Abstract: I will review the constraints on H_0 from the Planck CMB measurements and compare the best fit Planck model with recent results from ACTpol. The CMB value of H_0 is secure, yet is in tension with Cepheid based measurements of H_0.  Although the CMB  value is based on the Lambda CDM cosmology, there has been no compelling theoretical modification of the model that can explain the tension. I will therefore explore  whether systematic errors may be affecting the Cepheid distance scale and if so, what must these errors look like.

Speaker (Affiliation): Netta Engelhardt (MIT)

Title: The Information Paradox in the Age of Holographic Entanglement Entropy

Abstract: 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 to find its resolution in the deep quantum gravity regime. Recent developments in the holographic dictionary and in particular its application to entanglement, however, have shown that a semiclassical analysis of gravitational physics has a hallmark feature of unitary evolution. I will describe this recent progress and discuss some potential new avenues for working towards a resolution of the information paradox.

Speaker (Affiliation): Pol Forn-Díaz (IFAE)

Title: A superconducting Qbit as a universal approximant 

Abstract: A single qubit can approximate any bounded complex function as stored in the degrees of freedom defining the quantum state. This result is analogue to two known theorems ensuring approximations for functions, namely Fourier series and the Universal Approximation Theorem (UAT), that holds for neural networks with a large enough single, intermediate hidden layer. The single qubit circuit becomes more accurate as the independent function variable is re-uploaded in an increasing number of gates, analogous to the classical methods that grow in accuracy with an increased number of intermediate steps. We further implement a one-qubit approximant in a real superconducting qubit device consisting of a transmon qubit in a three-dimensional cavity, explicitly showing how the ability to describe a set of functions improves with the depth of the quantum circuit.

Speaker (Affiliation): Manfred Lindner, (Max Planck Institute for Nuclear Physics, Heidelberg)

Title: The XENON1T excess

Abstract: The XENON1T experiment aims at detecting signatures of dark matter. The latest analysis showed, however, an unexpected excess of events with low recoil energy. The talk will cover in detail how the signal is obtained and different interpretations of this excess. The signal might point to new physics and several theoretical directions and their implications for future measurements and other experiments will be discussed.

Speaker (Affiliation): Thomas Schwetz-Mangold (Karlsruhe Institute of Technology)

Title: The fate of hints: recent developments in neutrino physics

Abstract: Finite neutrino mass points to new physics beyond the Standard Model. In this talk I give an overview over recent results in neutrino physics, including the results of a combined analysis of latest neutrino oscillation data. We comment on the implications of this years results for the type of neutrino mass ordering (normal versus inverted) and on the status of leptonic CP violation within the minimal 3-flavour framework. I review the status of absolute neutrino mass searches and searches for lepton-number violation. I will briefly discuss some examples for searches for more exotic physics in the neutrino sector, including sterile neutrinos. The guidline of my talk will be various "hints" for standard as well as non-standard physics, which have been around for some time in neutrino data, and their fate due to recent developements.

Speaker (Affiliation): Jesse Thaler (MIT)

Title: Collider Physics and Machine Learning

Abstract: Modern machine learning has had an outsized impact on many scientific fields, and particle physics is no exception.  What is special about particle physics, though, is the vast amount of theoretical and experimental knowledge that we already have about many problems in the field.  In this talk, I draw on examples from collider phenomenology and quantum chromodynamics to highlight the fascinating interplay between theoretical principles and machine learning strategies.