arXiv subjects

Pablo Leon

Publications and source records attributed to Pablo Leon.

4 recordsLinked to original sources

arXiv2026

Discovery of Polymer Electrolytes with Bayesian Optimization and High-Throughput Molecular Dynamics simulations

Polymer electrolytes are critical for safe, high-energy-density solid-state batteries, yet discovering candidates that balance high ionic conductivity with high transference numbers remains a significant challenge. In this work, we develop a high-throughput screening platform that utilizes molecular dynamics simulations to navigate a chemical space of 1.7 million hypothetical polymer electrolyte candidates. Data from previous literature is used to warm-start batch Bayesian optimization for iteratively selecting new polymer electrolytes to evaluate. We iteratively identified, evaluated and analyzed 767 homopolymers as potential candidates. Our results reveal several candidates with transport properties exceeding the benchmark polyethylene oxide (PEO)/LiTFSI system. Crucially, our optimization campaigns for ionic conductivity and Li-diffusivity demonstrate that branched architectures and ketone functional groups significantly enhance ion-hopping mechanisms within the polymer matrix. We provide an in-depth mechanistic comparison of Li vs. Na cation transport and offer our open-source framework to accelerate the discovery of liquid, gel, and multi-cation electrolyte systems.

cond-mat.mtrl-sci↗

arXiv2024

On static and rotating decoupled black holes without inner horizons

Through gravitational decoupling using the extended minimal geometric deformation, a new family of static and rotating ``hairy'' black holes is provided. The background of these models is a generic Schwarzschild metric containing as special cases, the Schwarzschild, Schwarzschild-dS, Reissner-Nordstrom and Reissner-Nordstrom-dS black holes. Assuming the Kerr-Schild condition and a general equation of state, the unknown matter sector is solved given rise to black hole space-times without a Cauchy horizon, transforming the original time-like singularity of the Reissner-Nordstrom and Reissner-Nordstrom-dS black holes into a space-like singularity. This fact is preserved for the rotating version of all these solutions.

gr-qc↗

arXiv2024

Connecting Infinity to Soft Factors

In this note we study tree-level scattering amplitudes of gravitons under a natural deformation which in the large $z$ limit can be interpreted either as a $k$-hard-particle limit or as a $(n-k)$-soft-particle limit. When $k=2$ this becomes the standard BCFW deformation while for $k=3$ it leads to the Risager deformation. The hard- to soft-limit map we define motivates a way of computing the leading order behavior of amplitudes for large $z$ directly from soft limits. We check the proposal by applying the $k=3$ and $k=4$ versions to NMHV and N$^2$MHV gravity amplitudes respectively. The former reproduces in a few lines the result recently obtained by using CHY-like techniques in \cite{BCL}. The N$^2$MHV formula is also remarkably simple and we give support for it using a CHY-like computation. In the $k=2$ case applied to any gravity amplitude, the multiple soft-limit analysis reproduces the correct ${\cal O}(z^{-2})$ behavior while explicitly showing the source of the mysterious cancellation among Feynman diagrams that tames the behavior from the ${\cal O}(z^{n-5})$ of individual Feynman diagrams down to the ${\cal O}(z^{-2})$ of the amplitude.

hep-th↗

arXiv2024

Computing NMHV Gravity Amplitudes at Infinity

In this note we show how the solutions to the scattering equations in the NMHV sector fully decompose into subsectors in the $z\to \infty$ limit of a Risager deformation. Each subsector is characterized by the punctures that coalesce in the limit. This naturally decomposes the $E(n-3,1)$ solutions into sets characterized by partitions of $n-3$ elements so that exactly one subset has more than one element. We present analytic expressions for the leading order of the solutions in an expansion around infinite $z$ for any $n$. We also give a simple algorithm for numerically computing arbitrarily high orders in the same expansion. As a consequence, one has the ability to compute Yang-Mills and gravity amplitudes purely from this expansion around infinity. Moreover, we present a new analytic computation of the residue at infinity of the $n=12$ NMHV tree-level gravity amplitude which agrees with the results of Conde and Rajabi. In fact, we present the analytic form of the leading order in $1/z$ of the Cachazo-Skinner-Mason/CHY formula for graviton amplitudes for each subsector and to all multiplicity. As a byproduct of the all-order algorithm, one has access to the numerical value of the residue at infinity for any $n$ and hence to the corrected CSW (or MHV) expansion for NMHV gravity amplitudes.

hep-th↗