Events Daily

Wednesday, January 29, 2025
      

Simulating Outflow Behavior in the GASOLINE-based Cosmological Simulations
Changhyun Cho, New York University Abu Dhabi
Event Type: Informal Astro Talk
Time: 11:00 AM - 11:30 AM
Location: 726 Broadway, 940, CCPP Seminar
Abstract: We propose a new black hole feedback algorithm for the GASOLINE-based cosmological Zoom-in simulations, focusing on two feedback modes: thermal feedback for high-accretion rates, which heats the surrounding gas, while kinetic feedback for low-accretion rates, which imparts momentum to simulate AGN-driven outflows and jets. Both modes incorporate realistic opening angles to better model the complex gas dynamics near the black hole, leading to a more physically realistic representation of galaxy evolution. Our model has successfully fit across several cosmological scaling relations, such as stellar mass vs. halo mass and black hole mass vs. stellar mass, while also producing more rotation-supported, disk-like morphologies. These results are consistent with observational evidence and offer new insights into the development of galaxy evolution. While further refinement and testing are necessary, this model presents a promising tool for advancing our understanding of galaxy formation and evolution, particularly in high-mass elliptical galaxies.

Emergent local physics in Quantum Gravity
Sam Leutheusser, Institute for Advanced Study
Event Type: HEP Seminar
Time: 2:00 PM - 3:15 PM
Location: 726 Broadway, 940, CCPP Seminar
Abstract: An important property for any candidate theory of quantum gravity is the emergence of classical geometry in an appropriate limit. We describe a framework to understand this emergence using von Neumann algebras as probes of local physics. In the context of the AdS/CFT correspondence, we demonstrate that many non-trivial "type III" algebras emerge in the limit where the number of local degrees of freedom of the boundary CFT becomes infinite. We argue that these non-trivial emergent boundary algebras: i) encode physical operations that can be performed in arbitrary bulk subregions, ii) are responsible for the causal structure of bulk geometry, and iii) describe how the boundary theory can perform non-local quantum tasks.

Link to the Event Video