Tootfinder

Dynamics of a data-driven low-dimensional model of Rayleigh-Benard convection
Qiwei Chen, Andres Castillo-Castellanos, C. Ricardo Constante-Amores
https://arxiv.org/abs/2507.11858

Dynamics of a data-driven low-dimensional model of Rayleigh-Benard convection
We present a multiscale, data-driven reduced-order framework for two-dimensional Rayleigh Benard convection in a square cell at high Rayleigh number, where the flow exhibits intermittent large-scale circulation reversals. Starting from direct numerical simulations using Nek5000, we extract a set of energy-ranked POD modes from the combined velocity and temperature fields. A Gaussian filter decomposes the temporal coefficients into low-frequency (slow) and high-frequency (fast) components, enabl…

The AdS Perspective on the Nonlinear Tails in Black Hole Ringdown
Alex Kehagias, Antonio Riotto
https://arxiv.org/abs/2506.14475 https://

The AdS Perspective on the Nonlinear Tails in Black Hole Ringdown
Black holes gradually settle into their static configuration by emitting gravitational waves, whose amplitude diminish over time according to a power-law decay at fixed spatial locations. We show that the nonlinear tails in the presence of a quadratic source, which have been recently found to potentially dominate over the linear ones, can be simply derived from the AdS$_2$$\times$S$^2$ spacetime perspective with their amplitudes being related to the Aretakis constants.

A Unified Theory of Compositionality, Modularity, and Interpretability in Markov Decision Processes
Thomas J. Ringstrom, Paul R. Schrater
https://arxiv.org/abs/2506.09499

A Unified Theory of Compositionality, Modularity, and Interpretability in Markov Decision Processes
We introduce Option Kernel Bellman Equations (OKBEs) for a new reward-free Markov Decision Process. Rather than a value function, OKBEs directly construct and optimize a predictive map called a state-time option kernel (STOK) to maximize the probability of completing a goal while avoiding constraint violations. STOKs are compositional, modular, and interpretable initiation-to-termination transition kernels for policies in the Options Framework of Reinforcement Learning. This means: 1) STOKs can…

Spatially resolved H$\alpha$ emission in B14-65666: compact starbursts, ionizing efficiency and gas kinematics in an advanced merger at the Epoch of Reionization
C. Prieto-Jim\'enez, J. \'Alvarez-M\'arquez, L. Colina, A. Crespo G\'omez, A. Bik, G. \"Ostlin, A. Alonso-Herrero, L. Boogaard, K. I. Caputi, L. Costantin, A. Eckart, M. Garc\'ia-Mar\'in, S. Gillman, J. Hjorth, E. Iani, I. Jermann, A. Labiano, D. Langeroodi, J. Melinder, T. Moutard, F. Pei{\ss}ker,…

Spatially resolved H$α$ emission in B14-65666: compact starbursts, ionizing efficiency and gas kinematics in an advanced merger at the Epoch of Reionization
We present MIRI/JWST medium resolution spectroscopy (MRS) and imaging (MIRIM) of B14-65666, a Lyman-break and interacting galaxy at redshift $z$=7.15. We detect the H$α$ line emission in this system, revealing a spatially-resolved structure of the H$α$ emitting gas, which consists of two distinct galaxies, E and W, at a projected distance of 0.4". Galaxy E is very compact in the rest-frame UV, while W galaxy is more extended, showing a clumpy structure reminiscent of a tidal tail. The total H…

An In-situ Solid Fuel Ramjet Thrust Monitoring and Regulation Framework Using Neural Networks and Adaptive Control
Ryan DeBoskey, Parham Oveissi, Venkat Narayanaswamy, Ankit Goel
https://arxiv.org/abs/2506.08157

An In-situ Solid Fuel Ramjet Thrust Monitoring and Regulation Framework Using Neural Networks and Adaptive Control
Controlling the complex combustion dynamics within solid fuel ramjets (SFRJs) remains a critical challenge limiting deployment at scale. This paper proposes the use of a neural network model to process in-situ measurements for monitoring and regulating SFRJ thrust with a learning-based adaptive controller. A neural network is trained to estimate thrust from synthetic data generated by a feed-forward quasi-one-dimensional SFRJ model with variable inlet control. An online learning controller base…

Ranked choice voting (RCV)
is an increasingly popular electoral institution that has been posited by reformers and media outlets to produce transformative effects on electoral outcomes and representation.
This article finds no empirical support for the proposition that RCV changed fiscal outcomes or the ideological composition of city councils
— both on absolute terms and relative to mass opinion.
Furthermore, the roll-call based ideal points of legislators serving …

Primordial Black Hole Ringdown: the Irreducible Stochastic Gravitational Wave Background
Valerio De Luca, Antonio J. Iovino, Antonio Riotto
https://arxiv.org/abs/2507.04083

Primordial Black Hole Ringdown: the Irreducible Stochastic Gravitational Wave Background
Independently from the formation mechanism of primordial black holes in the early universe, their generation is accompanied by a ringdown phase during which they relax to a stationary configuration and gravitational waves under the form of quasinormal modes are emitted. Such gravitational waves generate an irreducible and unavoidable stochastic background which is testable by current and future experiments. In particular, the presence of a primordial black hole ringdown allows to significantly …

SAKURAONE: Empowering Transparent and Open AI Platforms through Private-Sector HPC Investment in Japan
Fumikazu Konishi
https://arxiv.org/abs/2507.02124 ht…

SAKURAONE: Empowering Transparent and Open AI Platforms through Private-Sector HPC Investment in Japan
SAKURAONE is a managed high performance computing (HPC) cluster developed and operated by the SAKURA Internet Research Center. It reinforces the ``KOKARYOKU PHY'' configuration of bare-metal GPU servers and is designed as a cluster computing resource optimized for advanced workloads, including large language model (LLM) training. In the ISC 2025 edition of the TOP500 list, SAKURAONE was ranked \textbf{49th} in the world based on its High Performance Linpack (HPL) score, demonstrating its glob…

This https://arxiv.org/abs/2504.14978 has been replaced.
link: https://scholar.google.com/scholar?q=a

clusttraj: A Solvent-Informed Clustering Tool for Molecular Modeling
Clustering techniques are consolidated as a powerful strategy for analyzing the extensive data generated from molecular modeling. In particular, some tools have been developed to cluster configurations from classical simulations with a standard focus on individual units, ranging from small molecules to complex proteins. Since the standard approach includes computing the Root Mean Square Deviation (RMSD) of atomic positions, accounting for the permutation between atoms is crucial for optimizing …

This https://arxiv.org/abs/2502.07662 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_…

Exploring the mysterious high-ionization source powering [Ne V] in high-z analog SBS0335-052 E with JWST/MIRI
Nearby blue compact dwarf galaxies (BCDs) share similar properties with objects from the Epoch of Reionization revealed by JWST, in terms of low stellar mass, low metallicity and high specific star-formation rate. Thus, they represent ideal local laboratories for detailed multi-wavelength studies to understand their properties and the mechanisms shaping them. We report the first JWST MIRI/MRS observations of the BCD SBS 0335-052 E, analyzing MIR emission lines tracing different levels of ioniza…