Scuola Internazionale Superiore di Studi Avanzati

Machine Learning the Nonradiative Decay Modes in Photochemical Processes

Abstract Nonradiative decay in photoexcited molecular systems is driven by nuclear motion toward conical intersections (CIs), where electronic states become degenerate and nonadiabatic transitions occur. Identifying the nuclear degrees of freedom responsible for CI access from no...

Resolving the Nature of the Lowest-Frequency Raman Mode of Liquid Water

Abstract The lowest-frequency Raman mode of water, observed through depolarized light scattering or optical Kerr effect techniques, is routinely used to track dynamic changes of interfacial water near ions or biomolecules. Despite this broad importance, its microscopic origin and...

MicroRNA 517a-3p suppresses α-synuclein fibril accumulation in human glioblastoma cells

Abstract Background Synucleinopathies are a group of neurodegenerative disorders characterized by the misfolding, aggregation, and accumulation of α-synuclein (α-syn) into oligomeric assemblies and amyloid inclusions. Alongside neurons, glial cells can internalize pathological α-...

A Fermion Primer

This is a review paper intended to illustrate a few critical issues concerning Dirac, Weyl, and Majorana fermions and their differences. The first part consists of a basic introduction to fermions, with further detail on fermions in 4d, focusing in particular on what differentiat...

Variance reduction for forces and pressure in variational Monte Carlo

We present simple and practical strategies to reduce the variance of Monte Carlo estimators. Our focus is on variational Monte Carlo calculations of atomic forces and pressure in electronic systems, although we show that the underlying ideas apply more broadly to other observable...

Torsion parallel pure spinors on neutral manifolds

Abstract We study irreducible real pure spinors on pseudo-Riemannian manifolds of neutral signature using the theory of real spinorial forms. We prove that the square of such a spinor is a decomposable differential form of middle degree satisfying a natural duality condition. In...

Mosco-Convergence of Convex Sets and Unilateral Problems for Differential Operators with Lower Order Terms Having Natural Growth

We study the stability of solutions to a class of variational inequalities posed on obstacle-type convex sets, under Mosco-convergence. Specifically, we consider problems of the form {u∈W01,p(Ω)∩L∞(Ω),u≥ψ in Ω,⟨A(u),v−u⟩+∫ΩH(x,u,Du)(v−u)≥0,∀ v∈W01,p(Ω)∩L∞(Ω),v≥ψ in Ω. Here, A is...

Beyond the Virial Expansion: Microscopic Origins of Partial Molar Volumes in LiCl Solutions

Abstract Although electrolyte density measurements have been reported for over a century, employing them to determine accurate partial molar volume (PMV) profiles as a function of salt concentration has remained elusive. Obtaining such curves requires precise density measurements...

The Simons Observatory: Development of a Pipeline to Detect Rapid Transients in Time-Ordered Data

We introduce a method for detecting astrophysical transients evolving on timescales of milliseconds to minutes using cosmic microwave background (CMB) survey telescopes. While previous transient searches in CMB data operate in map space, our pipeline directly processes the raw ti...

Perceptual misalignment of texture representations in convolutional neural networks

Mathematical modeling of visual textures traces back to Julesz's intuition that texture perception in humans is based on local correlations between image features. An influential approach for texture analysis and generation generalizes this notion to linear correlations between t...

Steady Vortex Sheets in Presence of Surface Tension

Abstract In this paper, we construct a new class of uniformly rotating vortex sheets arising as perturbations of the circular configuration within the Kelvin–Helmholtz model for two incompressible fluids of equal density, with surface tension effects taken into account. Despite t...

Addressing the Limits of Emx2 Therapy of Glioblastoma Multiforme by Transgene Insulation and Epigenetic Pharmacological Intervention

Introduction/Objectives: Implicated in the regionalization of the anterior central nervous system (CNS) and the progression of pallial astrogliogenesis, the transcription factor gene EMX2 has been reported to be specifically silenced in several tumors, both non-neural and neural....

Investigating causality between principal components in protein dynamics

Principal component analysis (PCA) is widely used to characterize collective protein motions from molecular dynamics (MD) simulations. While PCA identifies the dominant modes of structural fluctuation, it does not reveal whether different principal components (PCs) causally influ...

Machine‐Learning Enhanced Parametric Reynolds‐Averaged Navier‐Stokes Equations at the Full‐ and Reduced‐Order Levels

ABSTRACT In this contribution, we focus on the Reynolds‐averaged Navier‐Stokes (RANS) models and their exploitation to build reliable reduced‐order models to further accelerate predictions for real‐time applications and many‐query scenarios. Specifically, we investigate how machi...

Conformal Symmetry, SM and Gravity

This paper is a bottom-up attempt to incorporate the standard model and general relativity in a unique quantum field theory. In particular, the tentative model presented here is free of chiral gauge and gravitational anomalies that appear in the divergence of currents and in the...

Noisy models of the ventral stream reveal the impact of recurrence and learned representations on information processing timescales

A bstract In vision neuroscience, the temporal dynamics of the sensory stream and of its neural representations are thought to be deeply linked to the function of the hierarchy of cortical areas that deal with object recognition, known as the visual ventral stream. Neural represe...

Modular Transformations of Tau Functions and Conformal Blocks on the Torus

Abstract The connection problem for isomonodromic tau functions on the one-punctured torus concerns the ratio between the tau function and its modular transform, associated to dual pants decompositions of the torus. In this paper, we study the modular transformations of the tau f...

A three-dimensional morphoelastic model for self-oscillations in polyelectrolyte hydrogel filaments

Abstract We introduce a three-dimensional model for polyelectrolyte hydrogel filaments operating in a fluid environment under an electric field. The formulation builds on a morphoelastic framework for inextensible and unshearable rods, such that the filament’s activity is encoded...

Polynomial Prethermal Lifetimes in Non Smoothly Driven Quantum Systems

Abstract We study the dynamics of a quantum many-body lattice system with a local Hamiltonian subjected to a quasi-periodic driving with finite regularity. For sufficiently large driving frequencies, we prove that the system remains in a prethermal state for times growing polynom...

A quality measure for repeating multiple-unit spike patterns

We propose a quality measure for spatio-temporal spike patterns (STPs) in multiple-neuron recordings. In such recordings, repeating STPs or pattern repetitions (PRs) are often found, with many of these generated by chance. To rule those out, statistical tests have been developed...