Title: Our Expanding Universe: What Lies Ahead?

Abstract: Our Universe is expanding at an increasing rate. What does the future hold? What will be here one billion years from now? A trillion years from now?.

Zoom Link: https://uky.zoom.us/j/88994568052

YouTube Link: You can find information about the impending nova, T Coronae Borealis, here- https://observatory.as.uky.edu/t-crb

• Star Trails at Raven Run.jpg
• (PDF maps on this page were created using Guide 9)

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After parking, please exit the parking structure come down one of the east exits, closest to the Young Library. 

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Dr. Paul Torrey, University of Virginia

Title: Simulating the Universe: From Illustris to DREAMS

Abstract: Over the past few decades, cosmological simulations have revolutionized how we study galaxy formation and the large-scale structure of the universe. By combining advances in computational methods, physical modeling and high-performance computing, these simulations now allow us to trace the evolution of cosmic structure from the earliest moments after the Big Bang to the richly structured galaxies we observe today. 

Projects such as Illustris and IllustrisTNG have provided detailed, physically grounded predictions for how galaxies form and evolve, capturing the interplay among dark matter, gas dynamics, star formation and feedback from supermassive black holes. The publicly released data from these simulations have become a cornerstone of modern extragalactic astrophysics, powering thousands of scientific studies worldwide and shaping how we interpret observations across wavelengths and cosmic time. 

In this talk, I will highlight some of the key insights these simulations have revealed, emphasizing both their predictive successes and the limits of our current physical understanding. I will also discuss how new approaches, specifically the DREAMS simulation framework, are enabling us to quantify uncertainty across large, high-resolved cosmological ensembles, transforming simulations from single “best guess” models into powerful statistical laboratories for testing theories of galaxy formation.

Dr. Hendrik Schatz, Michigan State University

Title: Rare Isotopes in the Cosmos

Abstract: Atomic nuclei with short lifetimes of fractions of seconds, so called rare isotopes, play an important role in the universe despite their fleeting existence. They serve as stepping stones for the synthesis of chemical elements, they shape the nature of stellar explosions, and they are the major constituents of neutron stars. I will give an overview of the role of rare isotopes in the cosmos and recent efforts to study astrophysical reactions involving rare isotopes at the Facility for Rare Isotope Beams at Michigan State University. As an example, I will discuss accreting neutron stars. These systems are among the brightest X-ray sources in the sky and exhibit an extraordinay range of rare isotope physics. By combining observations, astrophysical modeling, and nuclear physics experiments they can provide new insights into the behavior of matter under extreme temperatures and densities. 

Dr. Ambrose Seo, University of Kentucky

Title: Shaping Light and Charge in Two-Dimensional Materials with Plasmonic Nanostructures

Abstract: Two-dimensional materials such as MoS2 are just one atom thick, which gives them remarkable optical and electronic properties, but also makes them challenging to use efficiently in devices, since their ultrathin nature limits how strongly they interact with light. During my sabbatical in Seoul, I explored new ways to overcome this challenge by combining MoS2 with carefully designed metallic nanostructures that can trap and guide light at the nanoscale. By embedding gold or silver nanowires and nanogrooves beneath or alongside MoS2, we found that we could significantly boost its light emission, collect photo-generated charges more effectively, and improve the efficiency of heterostructures that pair MoS2 with oxide semiconductors. These studies show how "plasmonic" effects, i.e., collective oscillations of electrons in metals, can be harnessed to control light–matter interactions in atomically thin materials. I will present the key outcomes of these projects and discuss how they point toward future opportunities for next-generation devices.

Title: How "Little Red Dots" Broke the Universe (and how we're unbreaking it)

Abstract: One of the biggest mysteries of the early era of JWST's operation has been "Little Red Dots," compact sources with strange V shaped spectral energy distributions and broad emission lines. These sources have been incredibly hard to model, and over the course of three years, leading theories have ranged from over-massive galaxies that assembled Milky Way levels of stellar mass in the first Gyr of cosmic time to over-massive active galactic nuclei that defy models of black hole assembly. I will walk through the brief history of discover in this sources, demonstrating how we have slowly been getting closer and closer to understanding them by leveraging JWST, ALMA, and several other observatories to constrain their panchromatic spectral energy distribution. I will discuss our current best understanding of these sources, and how we might move forward to incorporate them into our picture of galaxy and black hole assembly.

Dr. Daniel Tataru, University of California, Berkeley

Title: Free boundary problems for Euler flows

Abstract: Free boundary problems are very interesting but also very challenging problems in fluid dynamics, where the boundary of the fluid is also freely moving along with the fluid flow. 

I will discuss two such models, governed by the compressible, respectively the incompressible Euler equations, including also MHD flows.  This is joint work with Mihaela Ifrim, and in part with Benjamin Pineau and Mitchell Taylor.

Title: Conformal prediction of future insurance claims in the regression problem

Abstract: In the current insurance literature, prediction of insurance claims in the regression problem is often performed with a statistical model. This model-based approach may potentially suffer from several drawbacks: (i) model misspecification, (ii) selection effect, and (iii) lack of finite-sample validity. This article addresses these three issues simultaneously by employing conformal prediction-a general machine learning strategy for valid predictions. The proposed method is both model-free and tuning-parameter-free. It also guarantees finite-sample validity at a pre-assigned coverage probability level. Examples, based on both simulated and real data, are provided to demonstrate the excellent performance of the proposed method and its applications in insurance, especially regarding meeting the solvency capital requirement of European insurance regulation, Solvency II.