Kavli Affiliate: Kohei Inayoshi | Summary:Recent observations have revealed a unique class of active galactic nuclei (AGNs), termed little red dots (LRDs). These objects are hypothesized to be powered by massive black holes rapidly accreting in dense gaseous environments. Theoretical studies suggest that the circum-nuclear gas can form an optically thick black hole envelope (BHE), […]
Kavli Affiliate: Andrew Vanderburg | Summary:Theoretical models predict that subgiants within a narrow mass regime can retain detectable lithium enrichment signatures from planetary engulfment. We test this prediction using TOI-5882, selected because it occupies this favorable subgiant parameter space and hosts a massive brown dwarf ($22 , M_ rm J$, $P=7.1 ,rm d$) companion capable […]
Kavli Affiliate: Felix Fischer | Summary:We study a family of Jacobi operators in which the diagonal entries are multiplied by a coupling parameter $λgeq0$. Under suitable conditions, the operator is self-adjoint for every $λ>0$, while the formal limit at $λ=0$ is a symmetric Jacobi operator admitting a one-parameter family of self-adjoint extensions. A central ingredient […]
Kavli Affiliate: Michael Fausnaugh | Summary:The observational determination of the lower limit of neutron star masses is crucial for the physics of core-collapse supernovae. In this light, SMC X-1 is an important object because of its estimated pulsar mass lying near or potentially below the theoretical lower limit. SMC X-1 exhibits a double peaked optical […]
Kavli Affiliate: David Muller | Summary:Transition metal dichalcogenide (TMD) moiré bilayers have realized a wide range of strongly correlated and topological phenomena. The physics in these materials is often sensitive to the interlayer stacking order. Polarization-resolved optical second harmonic generation (SHG) is the most used technique for stacking order characterization but unverified for most heterobilayers. […]
Kavli Affiliate: Feng Long| Summary: Low-rank adaptation (LoRA) has emerged as a powerful tool for parameter-efficient fine-tuning of large language models (LLMs). This paper studies LoRA under a federated learning setting, enabling collaborative fine-tuning across clients while preserving parameter efficiency. We focus on a highly heterogeneous regime in which clients share only partial structure and […]
Kavli Affiliate: Feng Long| Summary: We develop an adaptive jump test for discretely observed high-frequency semimartingales by combining the A"it-Sahalia–Jacod ratio statistic (A"it-Sahalia and Jacod, 2009) and the Lee–Mykland extreme-return statistic (Lee and Mykland, 2008) with the Cauchy combination rule. Allowing stochastic It^o drift, volatility, and leverage, we show asymptotic independence under the continuous-path null […]
Kavli Affiliate: Feng Long| Summary: We develop an adaptive jump test for discretely observed high-frequency semimartingales by combining the A"it-Sahalia–Jacod ratio statistic (A"it-Sahalia and Jacod, 2009) and the Lee–Mykland extreme-return statistic (Lee and Mykland, 2008) with the Cauchy combination rule. Allowing stochastic It^o drift, volatility, and leverage, we show asymptotic independence under the continuous-path null […]
Kavli Affiliate: Timothy Brown | Authors: Kristen C Ruegg, Christen M Bossu, Reza Goljani Amirkhiz, Nikunj Goel, Erica CN Robertson, Timothy M Brown, Kathryn Bernier, Ben J Vernasco, Peri E Bolton, Erik R Funk, Scott A Taylor, Mevin B Hooten and Erika S Zavaleta | Summary: Accelerated warming at high elevations is having a disproportionate […]
Kavli Affiliate: Massimo Scanziani and Jeanne Paz | Authors: Joshua M. Brenner, Sarah Ruediger, Cameron Wilhite, Josue M. Regalado, Yuta Senzai, Yuliya Voskobiynyk, Jeanne T. Paz, Massimo Scanziani and Riccardo Beltramo | Summary: Mammals rely on their senses to establish their position in space. Neural activity in the hippocampus maps position, yet how sensory signals […]