Speaker: Zhengkang Zhang
Title: Structures of Neural Network Effective Theories
Room: 3024
Host: Luty
Abstract: The talk will discuss an intriguing connection between neural networks and effective field theories, and introduce a diagrammatic approach to perform calculations in these theories which makes transparent the structures of RG flows underlying the success of critical tuning of deep neural networks. Based on arXiv:2305.02334.
Speaker: Shruti Paranjape
Title: Double Copy, Soft Behaviour and Non-Linear Sigma Models
Room: 3024
Host: John Terning
Abstract: The double copy was originally a technique used to construct gravitational amplitudes from gluonic ones. It has since been extended to include other effective field theories. In this talk, we will focus on non-linear sigma models that result from spontaneous symmetry-breaking (e.g. chiral perturbation theory). We will discuss why these models are special at leading order. Beyond the leading order, we will understand how different leading-order properties (e.g. double soft theorems, extended theories, color-kinematics duality etc.) constrain higher-derivative corrections. We find that some properties must be preserved due to the double copy structure, some may not be and some others seem to be preserved with no known explanation.
Speaker: Hongwan Liu
Title: Cosmological Signatures of Dark Photons
Room: 3024
Zoom: https://zoom.us/j/186024391
Host: Hsin-Chia Cheng
Abstract: Cosmological observables are particularly sensitive to the existence of ultralight dark photons. I will describe the physics of conversions between visible and dark photons, and discuss how to use both the cosmic microwave background and the Lyman-alpha forest to look for such conversions.