BEGIN:VCALENDAR VERSION:2.0 PRODID:-//CERN//INDICO//EN BEGIN:VEVENT SUMMARY:Do Lyapunov exponents measure chaos? DTSTART;VALUE=DATE-TIME:20260413T160000Z DTEND;VALUE=DATE-TIME:20260413T162000Z DTSTAMP;VALUE=DATE-TIME:20261017T094951Z UID:indico-contribution-23-283@fisindico.uniandes.edu.co DESCRIPTION:Speakers: Jorge Kurchan (ENS Paris)\nThe solar system has a re latively large Lyapunov exponent\, and yet has been stable for much longer than the inverse Lyapunov time. Similarly\, almost integrable systems lik e the low energy Fermi-Pasta-Ulam chain take much longer to thermalize tha n one would expect from their Lyapunov exponent.\nThis phenomenon has more recently been studied in quantum systems.\n\nEl sistema solar tiene un ex ponente de Lyapunov relativamente grande y\, sin embargo\, ha permanecido estable durante mucho más tiempo que el inverso del tiempo de Lyapunov. D e manera similar\, sistemas casi integrables como la cadena de Fermi–Pas ta–Ulam a baja energía tardan mucho más en termalizar de lo que cabrí a esperar a partir de su exponente de Lyapunov.\nEste fenómeno ha sido es tudiado más recientemente en sistemas cuánticos.\n\nhttps://fisindico.un iandes.edu.co/event/23/contributions/283/ LOCATION:Universidad Nacional de Colombia Ed. 564 URL:https://fisindico.uniandes.edu.co/event/23/contributions/283/ END:VEVENT BEGIN:VEVENT SUMMARY:The complex evolution of chess openings DTSTART;VALUE=DATE-TIME:20260416T193000Z DTEND;VALUE=DATE-TIME:20260416T195000Z DTSTAMP;VALUE=DATE-TIME:20261017T094951Z UID:indico-contribution-23-305@fisindico.uniandes.edu.co DESCRIPTION:Speakers: Rafael Hurtado (Universidad Nacional de Colombia)\nC hess is a board game that demands deep positional understanding from the v ery first move of the opening to the end of the game. The initial moves\, by both White and Black\, contain information at the individual level abou t each player’s strengths\, knowledge of the adversary\, and personal pr eferences\, as well as broader insights into the state of the art of the g ame itself. The evolution of chess can be traced back to the fifteenth cen tury\, with major transformations linked to the formal establishment of ru les—such as Ruy López’s treatise—\, the beginning of organized tour naments in London\, the formation of FIDE—Fédération Internationale de s Échecs or International Chess Federation\, and the establishment of the Chess Olympiads. Several tournaments have been reserved for high-level pl ayers\, with selection processes ranging from direct invitations\, such as the Hastings call\, to eliminatory systems like the Chess Olympiads and t he World Championship Candidates Tournament. Participants in these events bring well-established strategies and techniques\, and innovations that em erge from the global practice of chess.\nIn this study\, we analyze the de velopment of chess openings over the course of a century\, using the compl ete dataset of matches played in the Olympiads from 1924 to 2024. We combi ne two theoretical and methodological approaches: on one hand\, we represe nt matches and tournaments using graphs\; on the other\, we apply entropy measures and complexity indices to explore and trace the organizational pr ocesses underlying the evolution of the game. Graphs are constructed by ad ding directed dyads corresponding to the first move of each match\, with n odes representing Black’s responses to White’s moves using Descriptive Notation (e.g.\, Pawn to King 4 as PK4)\, recorded in a 20×20 matrix. We compute the following measures of complexity: Shannon entropy\, Tsallis e ntropy\, the Shiner-Davison-Landsberg complexity index\, and the López-Ru iz-Mancini complexity index—based on both degree and strength of the nod es. These are analyzed across three match outcomes: White wins\, Black win s and draws. In- and out-degree and strength are associated with the playe r’s perspective (White or Black)\, while outcomes are treated as subsyst ems to estimate Tsallis entropy. Our results show that chess has evolved t owards increasing diversity\, due to broader explorations and preferences for rare strategies\, reflecting both innovation and adaptation to evolvin g winning patterns: While Shannon entropy captures the growing dispersion of opening choices and shifts in player´s preferences\, and complexity in dices highlight rising interdependence between moves\, assuming superaddit ivity Tsallis entropy parameter (q)\, ranges from 1.1 to 3.0\, signals a t ransition toward correlated structures.\n\nhttps://fisindico.uniandes.edu. co/event/23/contributions/305/ LOCATION:Universidad de los Andes ML-513 URL:https://fisindico.uniandes.edu.co/event/23/contributions/305/ END:VEVENT BEGIN:VEVENT SUMMARY:Threeway out of equilibrium many body dynamics DTSTART;VALUE=DATE-TIME:20260413T190000Z DTEND;VALUE=DATE-TIME:20260413T203000Z DTSTAMP;VALUE=DATE-TIME:20261017T094951Z UID:indico-contribution-23-354@fisindico.uniandes.edu.co DESCRIPTION:Speakers: Frédéric van Wijland (Université Paris Cité)\nTh ese three lectures will focus on three manners to fall out of equilibrium\ , and on the many-body effects that arise from the nonequilibrium nature o f the dynamics. We will begin with systems harboring a macroscopic current (leading to long range correlations). Then we shall stop by systems that should be relaxing towards equilibrium\, but that fail to do so for reason s that are still under investigation. And the final lecture will concern s ystems with no macroscopic current that are nevertheless maintained out of equilibrium by a constant input of energy that drives the individual moti on of the particles.\n\n1. Out of equilibrium with a macroscopic current: Driven Systems\n - Macroscopic Fluctuation Theory\n - The possibil ity of phase transitions in one dimension\n2. Out of equilibrium\, but los t on the way to equilibrium: Glasses\n - Mode-coupling approach\n - Infinite-dimensional insight\n3. Out of equilibrium\, because that's lif e: Active Matter\n - From one particle to many\n - Field theories for active matter\n\nhttps://fisindico.uniandes.edu.co/event/23/contributi ons/354/ LOCATION:Universidad Nacional Ed. 564 URL:https://fisindico.uniandes.edu.co/event/23/contributions/354/ END:VEVENT BEGIN:VEVENT SUMMARY:Temporal fluctuation scaling and thermostatistical study of the pe r capita gross domestic products of 105 countries of the world during the period 1960-2023 DTSTART;VALUE=DATE-TIME:20260416T201000Z DTEND;VALUE=DATE-TIME:20260416T203000Z DTSTAMP;VALUE=DATE-TIME:20261017T094951Z UID:indico-contribution-23-339@fisindico.uniandes.edu.co DESCRIPTION:Speakers: Alejandro Riascos Ochoa (Universidad Nacional de Col ombia)\nWe perform an econophysics study of the gross domestic product per capita (GDPP) data from $N=105$ countries worldwide\, which have annual r ecords in the World Bank database for every year between 1960 and 2023.\nS tarting from the time series of annual values of the average GDPP per coun try and the variance of the GDPP for the period 1960-2023\, we find that t he variance presents a power law relationship with respect to the average\ , that is\, the existence of the scaling of the temporal fluctuation in th is economic system is verified.\nSubsequently\, after verifying that there is also scaling of the time fluctuation for 15-year observation windows\, we studied the annual evolution of the values of the proportionality cons tant and the exponent of the scaling of the time fluctuation during the pe riod 1974-2023\, observing the existence of anticorrelated cycles for thes e two quantities.\nFinally\, defining the economic temperature (Te) as the first absolute moment of the 105 GDPP values with respect to the average GDPP per country\, the economic entropy (Se) as the average Shannon entrop y per country multiplied by $N$\, and the economic chemical potential (Pe) by establishing an analogy with the first law of thermodynamics\, we stud y the temporal evolution of the macroscopic variables Te\, Se\, and Pe ove r the period 1960–2023.\nWe find that\, in terms of these macroscopic va riables\, it is possible to identify historical periods in which different economic factors led to growth or decline dynamics in the annual values o f both the average GDPP per country and the variance of GDPP.\n\nhttps://f isindico.uniandes.edu.co/event/23/contributions/339/ LOCATION:Universidad de los Andes ML-513 URL:https://fisindico.uniandes.edu.co/event/23/contributions/339/ END:VEVENT BEGIN:VEVENT SUMMARY:Sobreviviendo la era de LLMs DTSTART;VALUE=DATE-TIME:20260414T210000Z DTEND;VALUE=DATE-TIME:20260414T212000Z DTSTAMP;VALUE=DATE-TIME:20261017T094951Z UID:indico-contribution-23-282@fisindico.uniandes.edu.co DESCRIPTION:Speakers: Raul Ramos Pollán (Universidad de Antioquia)\nSi bi en los LLMs han irrumpido con excepcional fuerza en el campo de la IA con una percepción de un potencial de impacto y cambio enorme\, su adopción para resolver problemas en la práctica sigue planteando muchísimos retos . Su naturaleza como modelos estadísticos del lenguaje es la causa princi pal de estas dificultades y\, en ese contexto se han creado muchas técnic as que permiten abordar parte de estos retos en distintas circunstancias. Esto incluye técnicas como grounding\, continual pretraining\, thinking m odels\, etc. En esta charla revisaremos algunos casos en la industria y en la investigación donde relucen estas limitaciones y las aproximaciones q ue con las que estamos intentando explotar ese potencial prometido.\n\nhtt ps://fisindico.uniandes.edu.co/event/23/contributions/282/ LOCATION:Universidad Nacional Ed. 564 URL:https://fisindico.uniandes.edu.co/event/23/contributions/282/ END:VEVENT BEGIN:VEVENT SUMMARY:La Relación de Crooks aplicada a sistemas de dos osciladores arm ónicos acoplados simulados bajo movimiento browniano DTSTART;VALUE=DATE-TIME:20260416T213000Z DTEND;VALUE=DATE-TIME:20260416T215000Z DTSTAMP;VALUE=DATE-TIME:20261017T094951Z UID:indico-contribution-23-320@fisindico.uniandes.edu.co DESCRIPTION:Speakers: Jose Daniel Muñoz Castaño (Departamento de Física \, Universidad Nacional de Colombia\, Bogotá)\nLa Relación de Crooks [1] \, uno de los teoremas de fluctuación\, es hoy en día un método estánd ar para calcular diferencias de energía libre entre dos estados de un sis tema utilizando procesos fuera del equilibro. En el presente trabajo const ruimos un sistema de dos osciladores armónicos de masa y resorte en un b año térmico acoplados por un tercer resorte\, y simulamos mediante diná mica browniana el proceso directo por el cual separamos los osciladores ha sta que el enlace entre ellos se rompe\, para luego volver a juntarlos en un proceso reverso durante el cual el enlace entre ellos se restablece. En un segundo sistema\, el resorte de acople vuelve a aparecer al final del proceso de estirado. Al trazar las curvas de fuerza vs. elongación y medi r para muchas repeticiones los histogramas de los trabajos realizados en l os procesos directo y reverso\, es posible usar la Relación de Crooks par a calcular la diferencia de energía libre entre los estados inicial y fin al. Nuestros resultados evidencian que la Relación de Crooks es capaz de predecir con exactitud del 1% la diferencia de energía libre entre los en sambles canónicos inicial y final\, incluso al ejecutar el protocolo con velocidades tres órdenes de magnitud mayores que las de la evolución cua si-estacionaria. Además\, las curvas obtenidas de fuerza vs elongación s e asemejan a las obtenidas en experimentos con horquillas de ARN [3]. Los sistemas propuestos no sólo ilustran el funcionamiento y significado conc eptual de la Relación de Crooks\, sino que también podrían usarse como punto de partida para construir modelos simplificados de moléculas bioló gicas.\n\n[1] Crooks\, G. E. Phys. Rev. E 60\, 2721-2726 (1999).\n[2] Juli án David Jiménez Paz\, “La relación de Crooks: trabajo y energía lib re en osciladores acoplados fuera del equilibrio”\, Trabajo de Grado\, F ísico. Director Prof. José Daniel Muñoz\, Universidad Nacional de Colom bia\, Bogotá (2024).\n[3] D. Collin et. al\, Bustamante\, C. et al. Natur e 437\, 231-234 (2005).\n\nhttps://fisindico.uniandes.edu.co/event/23/cont ributions/320/ LOCATION:Universidad de los Andes ML-513 URL:https://fisindico.uniandes.edu.co/event/23/contributions/320/ END:VEVENT BEGIN:VEVENT SUMMARY:Antifragility of stochastic transport on networks with damage DTSTART;VALUE=DATE-TIME:20260413T210000Z DTEND;VALUE=DATE-TIME:20260413T212000Z DTSTAMP;VALUE=DATE-TIME:20261017T094951Z UID:indico-contribution-23-280@fisindico.uniandes.edu.co DESCRIPTION:Speakers: Leidy Katherin Eraso Hernandez (Universidad Nacional Autónoma de México)\nA system is called antifragile when damage acts as a constructive element improving the performance of a global function. In this work\, we analyze the emergence of antifragility in the movement of random walkers on networks with modular structures or communities. The ran dom walker hops considering the capacity of transport of each link\, where as the links are susceptible to random damage that accumulates over time. We show that in networks with communities and high modularity\, the locali zation of damage in specific groups of nodes leads to a global antifragile response of the system improving the capacity of stochastic transport to more easily reach the nodes of a network. Our findings give evidence of th e mechanisms behind antifragile response in complex systems and pave the w ay for their quantitative exploration in different fields.\n\nhttps://fisi ndico.uniandes.edu.co/event/23/contributions/280/ LOCATION:Universidad Nacional Ed. 564 URL:https://fisindico.uniandes.edu.co/event/23/contributions/280/ END:VEVENT BEGIN:VEVENT SUMMARY:Interplay of quantum resources: magic-protected entanglement DTSTART;VALUE=DATE-TIME:20260417T195000Z DTEND;VALUE=DATE-TIME:20260417T201000Z DTSTAMP;VALUE=DATE-TIME:20261017T094951Z UID:indico-contribution-23-350@fisindico.uniandes.edu.co DESCRIPTION:Speakers: Julian Rincón (Universidad de los Andes)\nEntanglem ent and magic (non-stabilizerness) are widely regarded as necessary for qu antum universality and potential advantage. Yet the form in which they mus t appear within a quantum state remains unclear. We introduce an operation al diagnostic of their interplay: \\emph{magic-protected entanglement}\, d efined as entanglement remaining after optimal stabilizer (Clifford) proce ssing. This reframes the heuristic ``entanglement~+~magic'' as a sharp ope rational question: how much entanglement is intrinsically linked to magic. This perspective endows the state space with structure\, distinguishing \ \emph{T-magic}--type states\, where magic is injected locally and entangle ment can often be removed by stabilizer processing\, from \\emph{W-magic}- -type states (including Dicke and non-stabilizer hypergraph families)\, wh ose entanglement cannot be completely undone by Clifford circuits. The res ulting separation enables a principled discussion of nonlocal quantum reso urces.\n\nhttps://fisindico.uniandes.edu.co/event/23/contributions/350/ LOCATION:Universidad de los Andes ML-513 URL:https://fisindico.uniandes.edu.co/event/23/contributions/350/ END:VEVENT BEGIN:VEVENT SUMMARY:Preisach-percolation dynamics of multilevel resistive switching in phase-separated LPCMO DTSTART;VALUE=DATE-TIME:20260416T153000Z DTEND;VALUE=DATE-TIME:20260416T155000Z DTSTAMP;VALUE=DATE-TIME:20261017T094951Z UID:indico-contribution-23-284@fisindico.uniandes.edu.co DESCRIPTION:Speakers: Juan Gabriel Ramirez (Universidad de los Andes)\nWe investigate the complex interplay of competing phases in bulk La$_{5/8−x }$Pr$_x$Ca$_3/8$MnO$_3$ (LPCMO) to demonstrate the coexistence of volatile and non-volatile multilevel resistive switching (RS) within a single devi ce. In this system\, ferromagnetic metallic (FM-M) and chargeordered insul ating (COI) phases spatially coexist across a broad ∼160 K temperature w indow. While volatile RS is driven by a reversible\, electrically induced metal-insulator transition\, the non-volatile RS is governed by the therma l history of the FM volume fraction. Specifically\, voltage pulses that he at the device into a critical 90–210 K window permanently alter the phas e fraction\, modulating the resistance by up to seven orders of magnitude (∼300 Ω to ∼109 Ω). The metallic state is fully recoverable by cyc ling the temperature above the charge-ordering threshold (∼210 K). To qu antitatively capture this phase-fraction control\, we implement a Preisach –percolation framework. Calibrated directly from experimental R–T hyst eresis loops without free parameters\, the model extracts domain switching distributions and utilizes a percolation threshold of $p_c = 0.65$ to suc cessfully predict both macroscopic resistance at 2 K and magnetization at 5 K following specific thermal pathways. Ultimately\, we demonstrate the s tabilization of three distinct\, highly reproducible resistance states ove r 25 cycles with ratios exceeding $10^3$\, showcasing phase-fraction engin eering as a robust mechanism for multilevel memory in correlated oxides. \ n\nKeywords: resistive switching\, phase separation\, Preisach model\, per colation theory\, LPCMO\, neuromorphic computing. \n\nAcknowledgements\nTh is work was conducted in collaboration with Diego Carranza-Celis (Universi dad de los Andes)\, Pavel Salev (University of Denver)\, Ali C. Basaran (G eneral Atomics)\, and Ivan K. Schuller (UC San Diego). J.G.R. acknowledges support from the Facultad de Ciencias and Vicerrectoría de investigacion es of Universidad de los Andes. This work was also supported by Project No . INV2021-128-2313 of the Faculty of Science at Universidad de los Andes\, Bogotá\, Colombia. The research at University of California\, San Diego was supported by the U.S. Department of Energy’s Office of Basic Energy Science\, under Grant No. DE-FG02-87ER45332.\n\nhttps://fisindico.uniandes .edu.co/event/23/contributions/284/ LOCATION:Universidad de los Andes ML-513 URL:https://fisindico.uniandes.edu.co/event/23/contributions/284/ END:VEVENT BEGIN:VEVENT SUMMARY:Path integral approach to work beyond the two-point measurement sc heme DTSTART;VALUE=DATE-TIME:20260417T210000Z DTEND;VALUE=DATE-TIME:20260417T212000Z DTSTAMP;VALUE=DATE-TIME:20261017T094951Z UID:indico-contribution-23-360@fisindico.uniandes.edu.co DESCRIPTION:Speakers: Carlos Viviescas (Universidad Nacional de Colombia)\ nThe conventional approach to characterize work statistics in driven quant um systems is the two-point measurement scheme (TPMS)\, where work is defi ned as the difference between two projective energy measurements performed at the beginning and end of an evolution protocol. This scheme has been s hown to be consistent with classical stochastic thermodynamics [1]\, and t o enable the identification of a work functional that converges to its cla ssical counterpart in the semiclassical limit [2].\n\n\nDespite its import ance\, since the initial projective energy measurement suppresses coherenc es in the initial state\, the TPMS is not suited to assess the role of ini tial coherence in quantum thermodynamics. In this work we present a path i ntegral formulation of two alternative schemes that preserve initial coher ences and are consistent with the TPMS for incoherent states described by quasi-probability distributions: i) the Margenau-Hill (MH) scheme [3]\, wh ere the explicit introduction of the initial projective measurement is avo ided by introducing an estimation of the initial Hamiltonian based on proj ective measurements at the end of the protocol only\, and ii) the so-calle d full counting statistics scheme [4]\, where the characteristic function is related to the phase accumulated by a detector coupled to the system. \ n\n\n[1] Lostaglio\, M. (2018). Quantum fluctuation theorems\, contextuali ty\, and work quasiprobabilities. Physical review letters\, 120(4)\, 04060 2.\n\n[2] Funo\, K.\, & Quan\, H. T. (2018). Path integral approach to qua ntum thermodynamics. Physical review letters\, 121(4)\, 040602. \n[3] Pei\ , J. H.\, Chen\, J. F.\, & Quan\, H. T. (2023). Exploring quasiprobability approaches to quantum work in the presence of initial coherence: Advantag es of the Margenau-Hill distribution. Physical Review E\, 108(5)\, 054109. \n\n[4] Solinas\, P.\, & Gasparinetti\, S. (2016). Probing quantum interfe rence effects in the work distribution. Physical Review A\, 94(5)\, 052103 .\n\nhttps://fisindico.uniandes.edu.co/event/23/contributions/360/ LOCATION: URL:https://fisindico.uniandes.edu.co/event/23/contributions/360/ END:VEVENT BEGIN:VEVENT SUMMARY:From motifs to Lévy flights: modeling urban mobility in Bogotá ’s public transport system DTSTART;VALUE=DATE-TIME:20260413T212000Z DTEND;VALUE=DATE-TIME:20260413T214000Z DTSTAMP;VALUE=DATE-TIME:20261017T094951Z UID:indico-contribution-23-324@fisindico.uniandes.edu.co DESCRIPTION:Speakers: Juan Felipe Alayón Martínez (Universidad Nacional de Colombia)\nPaper published in 2026: we study two years of access card v alidation records from Bogotá’s multimodal public transport system\, co mprising over 2.3 billion trips across bus rapid transit\, feeder buses\ , dual-service buses\, and an aerial cable network. From user trajectories constructed exclusively from access records\, we derive motifs that revea l recurrent mobility patterns extending beyond simple two-location visits. This approach enables the construction of an integrated origin–destinat ion (OD) matrix covering 2828 urban zones. Similarity analysis using the J ensen–Shannon divergence confirms the temporal stability of mobility str uctures across semesters\, despite infrastructure changes and fare policy adjustments. From the obtained OD matrices\, we derive transition probabil ities between zones and uncover a robust power-law relationship with geogr aphical distance\, consistent with Lévy flight dynamics. We validate our model using Monte Carlo simulations showing that reproduces both local and long-range displacements\, with similar scaling exponents across time. Th ese findings demonstrate that Bogotá’s public transport mobility can be effectively modeled through Lévy processes\, providing a novel framework for analyzing complex transportation systems based solely on user access records.\n\nhttps://fisindico.uniandes.edu.co/event/23/contributions/324/ LOCATION:Universidad Nacional Ed. 564 URL:https://fisindico.uniandes.edu.co/event/23/contributions/324/ END:VEVENT BEGIN:VEVENT SUMMARY:El escalamiento temporal de la temperatura de los sistemas complej os: Una nueva propiedad en la naturaleza DTSTART;VALUE=DATE-TIME:20260416T195000Z DTEND;VALUE=DATE-TIME:20260416T201000Z DTSTAMP;VALUE=DATE-TIME:20261017T094951Z UID:indico-contribution-23-281@fisindico.uniandes.edu.co DESCRIPTION:Speakers: Carlos José Quimbay Herrera (Universidad Nacional d e Colombia)\nLos sistemas complejos presentan diferentes tipos de escalami ento\, tales como el escalamiento de la fluctuación temporal caracterizad a por el hecho de que la dispersión de los datos en una serie de tiempo n o estacionaria (cuantificada mediante la variancia) satisface una relació n de ley de potencia con respecto al promedio de los datos\, o el escalami ento del Theil temporal en el que la dispersión de los datos en una serie de tiempo de trayectoria difusiva (cuantificada mediante el índice de Th eil) satisface una relación de ley de potencia con respecto al promedio d e los datos mediante una expresión que tiene cierta similitud con la exis tente en las transiciones de fase de segundo orden. El objetivo principal de esta charla es mostrar la existencia en la naturaleza de una nueva rela ción de escalamiento\, en la que la temperatura de los sistemas complejos definida como el primer momento central absoluto se relaciona mediante un a ley de potencia con respecto al promedio de los datos. La anterior relac ión de ley de potencia\, que es denominada escalamiento temporal de la te mperatura de los sistemas complejos\, está presente en diferentes tipos d e sistemas complejos de naturaleza económica\, social\, financiera\, mete orológica\, epidemiológica\, etc.\n\nhttps://fisindico.uniandes.edu.co/e vent/23/contributions/281/ LOCATION:Universidad de los Andes ML-513 URL:https://fisindico.uniandes.edu.co/event/23/contributions/281/ END:VEVENT BEGIN:VEVENT SUMMARY:StatMech Insights on Na+/I− Symporter transport cycle DTSTART;VALUE=DATE-TIME:20260417T212000Z DTEND;VALUE=DATE-TIME:20260417T214000Z DTSTAMP;VALUE=DATE-TIME:20261017T094951Z UID:indico-contribution-23-349@fisindico.uniandes.edu.co DESCRIPTION:Speakers: Alfonso Leyva (Pontificia Universidad Javeriana)\, M ario A Bianchet (Department of Biophysics and Biophysical Chemistry\, Joh ns Hopkins University School of Medicine)\nThe intrinsic transmembrane pro tein known as sodium iodide symporter (NIS) facilitates the active transpo rt of iodide across the basolateral membrane of thyroid follicular cells. Iodine is an essential molecule that is used to produce the classical thyr oid hormones.\nTo perform a molecular dynamics (MD) simulation\, we used s tructures of apo-NIS and NIS with I− and an oxyanion (ReO4−) bound to it. \nThe goal of our computational study was to explore the conformation al space of NIS and gain insights into the conformations it assumes over t he course of its transport cycle.\nWe prepared a realistic simulation syst em that included NIS Na+ + I− / Na+ + ReO4− complexes embedded in a ce ntral membrane with the mammalian lipid composition\, with two half-membra ne leaflets on either side. We simulated the membrane potential by applyin g a constant external electrical field to the system\, thereby bringing ab out the equivalent of a membrane potential. We are using this system to co nduct unbiased and enhanced dynamics (metadynamics\, Deep-Tica)\, a NPT st atistical ensemble\, with the program GROMACS (2023.3) and a modified CHAR MM36 force-field\, to include non-bonded interactions between I− and the oxyanion ReO4−. In order to determine the effects of the potential on t he outwardly open NIS events\, simulations were conducted with three diffe rent membrane potentials (0\, −70\, and −140 mV) using the wild-type N IS with the anion and oxyanion bound to it\, and using a double mutant wit h interesting transport characteristics.\nThe resulting MD trajectories ar e currently being analyzed using a Python 3.11 script and some public li braries such as mdtraj (v1.9)\, MDanalysis (v2.7)\, Pyemma (v2.5.12)\, ml colvs and pytorch for deep-learning analysis. Metadynamics calculations of the transport of I−/ReO4− free energy along the transport path are cu rrently being done for the different membrane potentials\, using funnel bi as metadynamics.\n\nhttps://fisindico.uniandes.edu.co/event/23/contributio ns/349/ LOCATION:Universidad de los Andes ML-513 URL:https://fisindico.uniandes.edu.co/event/23/contributions/349/ END:VEVENT BEGIN:VEVENT SUMMARY:Scaling limits of random curves via Schramm–Loewner evolution DTSTART;VALUE=DATE-TIME:20260417T214000Z DTEND;VALUE=DATE-TIME:20260417T220000Z DTSTAMP;VALUE=DATE-TIME:20261017T094951Z UID:indico-contribution-23-323@fisindico.uniandes.edu.co DESCRIPTION:Speakers: Leidy Milena Leal Abril (UPTC)\nThe Schramm–Loewne r Evolution (SLE) provides a rigorous framework for characterizing the sca ling limits of fractal curves\, encoding their geometric properties throug h the diffusion parameter of a Brownian motion and enabling a universal cl assification of stochastic growth processes. In this talk\, we introduce t he basic ideas behind SLE and discuss its role in understanding conformall y invariant scaling limits of critical lattice models\, such as coastlines and invasion percolation trees. We also discuss some limitations of this description and suggest possible directions for generalizations.\n\nhttps: //fisindico.uniandes.edu.co/event/23/contributions/323/ LOCATION:Universidad de los Andes ML-513 URL:https://fisindico.uniandes.edu.co/event/23/contributions/323/ END:VEVENT BEGIN:VEVENT SUMMARY:Very persistent random walkers reveal transitions in landscape top ology DTSTART;VALUE=DATE-TIME:20260413T162000Z DTEND;VALUE=DATE-TIME:20260413T164000Z DTSTAMP;VALUE=DATE-TIME:20261017T094951Z UID:indico-contribution-23-329@fisindico.uniandes.edu.co DESCRIPTION:Speakers: Jaron Kent-Dobias (ICTP-SAIFR & IFT-UNESP)\nIn large random systems\, certain behaviors are reliably predicted\, like the ener gy density of the ground state. The long-time behavior of many physical an d algorithmic dynamics is likewise predictable\, through DMFT and related approaches. But can these behaviors be connected to static structures of t he problem at hand\, like its energy landscape? Recently\, development of the Overlap Gap Property\, which depends on the existence of a system-span ning component of the energy level set\, suggests that static topological properties can predict the performance of the best algorithms. Here\, I wi ll describe progress towards predicting the performance of the mediocre bu t simple algorithms we usually use. We use the ergodicity of a random walk er to probe whether typical configurations belong to a system-spanning com ponent of the energy level set. Passive random walkers lose ergodicity at a depth associated with the glass transition\, but active random walkers r emain ergodic to greater depth. We argue that in the limit of infinite per sistence time\, the ergodicity-breaking transition coincides with the poin t at which system-spanning components become atypical\, and discuss connec tions with gradient descent dynamics.\n\nhttps://fisindico.uniandes.edu.co /event/23/contributions/329/ LOCATION:Universidad Nacional de Colombia Ed. 564 URL:https://fisindico.uniandes.edu.co/event/23/contributions/329/ END:VEVENT BEGIN:VEVENT SUMMARY:Active Quantum Particles from Engineered Dissipation DTSTART;VALUE=DATE-TIME:20260416T190000Z DTEND;VALUE=DATE-TIME:20260416T192000Z DTSTAMP;VALUE=DATE-TIME:20261017T094951Z UID:indico-contribution-23-351@fisindico.uniandes.edu.co DESCRIPTION:Speakers: Leticia F. Cugliandolo (Sorbonne Université\, Paris )\nWhile the physics of classical active particles—such as bacteria\,\ns ynthetic Janus colloids\, and bird flocks—is well-established via models like Active Brownian Motion (ABM)\, the extension of these principles to the quantum regime has only recently gained traction. This talk will first review the fundamental principles of classical self-propulsion\, highligh ting unique features of individual particle dynamics. We will then transit ion to new frameworks for Quantum Active Matter from Engineered Dissipatio n\, presenting three specific models and demonstrating that they all recov er the hallmark features of active motion.\n\nTalk based on the preprint w ith the same title\, by\nJeanne Gipouloux\, Matteo Brunelli\, Leticia Cugl iandolo\, Rosario Fazio\, Marco Schirò\narXiv:2603.19094\nhttps://arxiv.o rg/abs/2603.19094\n\nhttps://fisindico.uniandes.edu.co/event/23/contributi ons/351/ LOCATION:Universidad de los Andes ML-513 URL:https://fisindico.uniandes.edu.co/event/23/contributions/351/ END:VEVENT BEGIN:VEVENT SUMMARY:Criticality and non-reciprocity of catastrophic phase inversion in emulsions DTSTART;VALUE=DATE-TIME:20260417T155000Z DTEND;VALUE=DATE-TIME:20260417T161000Z DTSTAMP;VALUE=DATE-TIME:20261017T094951Z UID:indico-contribution-23-326@fisindico.uniandes.edu.co DESCRIPTION:Speakers: Andrea Scagliarini (Institute for Applied Mathematic s (IAC)\, National Research Council (CNR))\nThe production of concentrated emulsions involves high-shear flows and it is well known that at a critic al volume fraction the emulsion loses stability\, undergoing an extremely rapid process where the continuous and dispersed phases in the emulsion ex change roles. This process\, called catastrophic phase inversion\, which r esembles in several respects a dynamical phase transition\, has remained w idely elusive from an experimental and theoretical point of view. We prese nt state-of-the-art experimental and numerical data to support a dynamical -system framework capable of precisely highlighting the dynamics occurring in the system as it approaches the catastrophic phase inversion. The stud y clearly highlights that at high volume fractions\, dynamical changes in the emulsion morphology\, due to coalescence and breakup of droplets\, pla y a critical role in determining the emulsion rheology and stability. Addi tionally\, we show that at approaching the critical volume fraction\, the dynamics can be simplified as being controlled by the dynamics of a correl ation length represented\, in our systems\, by the size of the largest dro plet. This dynamics shares a close connection with non-reciprocal phase tr ansition where two different physical mechanisms\, coalescence and breakup s\, can get out of balance leading to large non-symmetric periodic excursi ons in phase space. We clarify the phenomenology observed and quantitative ly explain the essential aspect of the highly complex dynamics of stabiliz ed emulsions undergoing catastrophic phase inversion.\n\nhttps://fisindico .uniandes.edu.co/event/23/contributions/326/ LOCATION: URL:https://fisindico.uniandes.edu.co/event/23/contributions/326/ END:VEVENT BEGIN:VEVENT SUMMARY:Exploration mechanisms intrinsic to semantic networks and the nuan ced appraisal of lexical repetition occurrences DTSTART;VALUE=DATE-TIME:20260413T220000Z DTEND;VALUE=DATE-TIME:20260413T222000Z DTSTAMP;VALUE=DATE-TIME:20261017T094951Z UID:indico-contribution-23-338@fisindico.uniandes.edu.co DESCRIPTION:Speakers: Gustavo Espinosa Otalora ()\nSemantic memory is resp onsible for storing knowledge of concepts or meanings in the long term. Ba sed on the semantic network from the study by Goñi et al. (2011)\, we stu dy the efficiency and performance of the network using the switching rando m walker model for different transition biases between nodes. Diffusion in the network is described by Markov chains\, a process that allows the cal culation of descriptive random variables such as average first-pass time a nd entropy rate. The MFPT and the entropy rate are very useful measures be cause they provide information about how reachable a node is on average fr om any other node\, and the rate at which information can spread through t he network. In addition\, we designed a fluency test simulation model base d on the changing random walker (SRW) where the relationship between short -term memory (STM)\, the number of repetitions and the flexibility of chan ge is analyzed. STM was found to play an important role in verbal fluency performance\, at least as it relates to verbal fluency tests.\n\nhttps://f isindico.uniandes.edu.co/event/23/contributions/338/ LOCATION:Universidad Nacional Ed. 564 URL:https://fisindico.uniandes.edu.co/event/23/contributions/338/ END:VEVENT BEGIN:VEVENT SUMMARY:Wetting by active fluids DTSTART;VALUE=DATE-TIME:20260417T190000Z DTEND;VALUE=DATE-TIME:20260417T192000Z DTSTAMP;VALUE=DATE-TIME:20261017T094951Z UID:indico-contribution-23-352@fisindico.uniandes.edu.co DESCRIPTION:Speakers: Frédéric van Wijland ()\nIn equilibrium fluids\, w etting is controlled by the competition of three surface tensions between the three phases (liquid\, gas\, solid). When the particles comprising the fluid become self-propelled\, the question of wetting begins with a prope r definition of surface tension (which may not be unique out of equilibriu m). I will present a robust mechanics-based definition for surface tension . I will use this definition to explore the properties of a droplet at con tact with a solid. It will appear that the angle of contact of an active d roplet is no more governed by the Young-Dupré equation.\n\nWith Y. Zhao\, J. Tailleur\, A. Daerr\, R. Zakine\, Y. Kafri\n\nhttps://fisindico.uniand es.edu.co/event/23/contributions/352/ LOCATION: URL:https://fisindico.uniandes.edu.co/event/23/contributions/352/ END:VEVENT BEGIN:VEVENT SUMMARY:Critical time-dependent phenomena in diffusion generative models DTSTART;VALUE=DATE-TIME:20260414T215000Z DTEND;VALUE=DATE-TIME:20260414T215700Z DTSTAMP;VALUE=DATE-TIME:20261017T094951Z UID:indico-contribution-23-325@fisindico.uniandes.edu.co DESCRIPTION:Speakers: William Montaño (Egresado)\nIn recent years\, diffu sion generative models have become state-of-the-art for tasks such as imag e\, video\, and audio generation\, among others. More recently\, there has been growing interest in studying the statistical mechanics of these mode ls\, driven by the observation of apparent phase transitions during the sa mpling process. More specifically\, a symmetry breaking that resembles the one encountered in the Ising model. In this proposal\, a theoretical desc ription of the diffusion models is presented\, explaining what diffusion m odels are\, how they can be studied from perspective of equilibrium statis tical mechanics\, and how critical phenomena emerge in a simple case. Addi tionally\, a simple simulation using a feed forward network and two delta functions as the initial distributions provides some insight into the mode l's behavior near the critical point. The main objectives include a deeper investigation of this critical phenomenon\, with particular focus on ques tions concerning the relationship between data dimensionality and the numb er of spins in the Ising model\, as well as the emergence of scaling-free properties. Furthermore\, the development of new models is proposed to all ow for a more detailed observation and analysis of these critical behavior s.\n\nhttps://fisindico.uniandes.edu.co/event/23/contributions/325/ LOCATION:Universidad Nacional Edificio 564 URL:https://fisindico.uniandes.edu.co/event/23/contributions/325/ END:VEVENT BEGIN:VEVENT SUMMARY:El amplio espectro de la IA en temas estadísticos DTSTART;VALUE=DATE-TIME:20260414T212000Z DTEND;VALUE=DATE-TIME:20260414T215000Z DTSTAMP;VALUE=DATE-TIME:20261017T094951Z UID:indico-contribution-23-356@fisindico.uniandes.edu.co DESCRIPTION:Speakers: Carlos Lemoine (Centro Nacional de Consultoría)\nh ttps://fisindico.uniandes.edu.co/event/23/contributions/356/ LOCATION:Universidad Nacional Ed. 564 URL:https://fisindico.uniandes.edu.co/event/23/contributions/356/ END:VEVENT BEGIN:VEVENT SUMMARY:From ferrimagnetic to spin glass behavior and back in lamellar Mn oxides undoped and doped with Co DTSTART;VALUE=DATE-TIME:20260416T155000Z DTEND;VALUE=DATE-TIME:20260416T161000Z DTSTAMP;VALUE=DATE-TIME:20261017T094951Z UID:indico-contribution-23-306@fisindico.uniandes.edu.co DESCRIPTION:Speakers: Andrés Rosales Rivera (Universidad Nacional de Colo mbia\, Manizales)\nIn this work we describe magnetization measurements on lamellar Mn oxides un-doped and dope with Co. They show that the magnetic structure of this oxides system is extremely sensitivity to the (Co/Mn) ra tio. Special emphasis is given to the inverse susceptibility and the tempe rature derivative of the magnetic susceptibility. Interestingly\, the magn etic order changes from a typical ferrimagnetic one with two sublattices ( sample with Co/Mn = 0) to an unconventional ferrimagnetic one with many su blattices (sample with Co/Mn = 0.014) and\, subsequently\, to a possible s pin glass-type structure (sample with Co/Mn = 0.037)\, before finally back to a predominant typical ferrimagnetic order taking place at intermediate temperatures (sample with Co/Mn = 0.096) with increasing the (Co/Mn) rati o. The behavior of the susceptibility is described by means of its associa tion with the spatial range of correlations between the spins of the syste m. The possible mechanisms leading to such unusual changes of magnetic ord ering are discussed\, including the super exchange interaction\, double ex change interaction\, and the frustration associated to such magnetic inter actions.\n\nhttps://fisindico.uniandes.edu.co/event/23/contributions/306/ LOCATION:Universidad de los Andes ML-513 URL:https://fisindico.uniandes.edu.co/event/23/contributions/306/ END:VEVENT BEGIN:VEVENT SUMMARY:Encounter times of random walkers with simultaneous resetting on n etworks DTSTART;VALUE=DATE-TIME:20260414T215700Z DTEND;VALUE=DATE-TIME:20260414T220400Z DTSTAMP;VALUE=DATE-TIME:20261017T094951Z UID:indico-contribution-23-328@fisindico.uniandes.edu.co DESCRIPTION:Speakers: Cristian David Suarez Jimenez (Universidad Nacional de Colombia)\nIn this work\, we study the dynamics of multiple random walk ers on networks subject to a simultaneous resetting protocol\, whereby all walkers are synchronously returned to their respective initial nodes. For this collective Markovian process\, we derive exact analytical expression s for the mean first-encounter time\, defined as the average time required for all walkers to meet for the first time at a given node. These results are formulated in terms of the eigenvalues and eigenvectors of the transi tion matrices governing the dynamics without resetting\, providing a clear spectral interpretation of the impact of resetting on encounter processes . We further establish a general criterion for finite networks that determ ines when the introduction of a nonzero resetting probability reduces the mean first-encounter time and leads to an optimal resetting strategy. The theoretical predictions are illustrated through numerical results on regul ar and heterogeneous networks\, for encounters involving two or more walke rs\, and for combinations of local and nonlocal dynamics. Our findings dem onstrate that simultaneous resetting can significantly reduce encounter ti mes for specific targets and initial conditions\, while becoming ineffecti ve for highly exploratory dynamics or distant targets. The framework provi des a unified approach to collective search and encounter problems on netw orks with resetting.\n\nhttps://fisindico.uniandes.edu.co/event/23/contrib utions/328/ LOCATION:Universidad Nacional Edificio 564 URL:https://fisindico.uniandes.edu.co/event/23/contributions/328/ END:VEVENT BEGIN:VEVENT SUMMARY:Bosonisation of one-dimensional fermion systems and applications t o spin chains DTSTART;VALUE=DATE-TIME:20260414T230000Z DTEND;VALUE=DATE-TIME:20260414T230700Z DTSTAMP;VALUE=DATE-TIME:20261017T094951Z UID:indico-contribution-23-345@fisindico.uniandes.edu.co DESCRIPTION:Speakers: Camilo Moreno Alfaro (Universidad de los Andes)\nBos onisation is a technique to solve one-dimensional fermion models by transf orming them to bosonic systems. S. Coleman (1975) showed that the correlat ors of the massive Thirring model\, a one-dimensional Dirac fermion with s elf-interactions\, coincide with those of the Sine-Gordon boson\, and late r\, S. Mandelstam (1975) found the explicit map between these two systems. The identities found by Mandelstam generalise to a broader set of one-dim ensional fermion models\, that is\, those that can be associated to a boso n\, and whose properties can hence be studied in an often simpler way by m eans of this mapping.\nThe transformation between fermions and bosons\, ho wever\, is but a particular case of seeking equivalent models to a particu lar system in order to examine its behaviour in a potentially simpler way. Another example of such transformations is that of Jordan and Wigner (192 8)\, who developed a way to map quantum spin lattices to fermions. This pr oject seeks to examine quantum spin chains under the light of the Jordan-W igner transformation and a subsequent bosonisation\, which in many ways si mplify the study of the statistical and thermodynamic behaviour of the cha in.\n\nhttps://fisindico.uniandes.edu.co/event/23/contributions/345/ LOCATION:Universidad Nacional Edificio 564 URL:https://fisindico.uniandes.edu.co/event/23/contributions/345/ END:VEVENT BEGIN:VEVENT SUMMARY:Spin Glass Dynamics on Complex Hardware Topologies: A Bond-Correla ted Percolation Approach DTSTART;VALUE=DATE-TIME:20260416T163000Z DTEND;VALUE=DATE-TIME:20260416T165000Z DTSTAMP;VALUE=DATE-TIME:20261017T094951Z UID:indico-contribution-23-327@fisindico.uniandes.edu.co DESCRIPTION:Speakers: Viviana Gómez Ramírez (Universidad de los Andes)\n Understanding how frustration and disorder shape relaxation in complex sys tems is a central challenge in statistical physics and directly relevant t o quantum annealing. Spin-glass models provide a natural setting to addres s this problem\, as their energy landscapes are governed by competing inte ractions and constrained network topologies. In this talk\, I explore the non-exponential relaxation dynamics of spin glasses defined on hardware-re levant graphs such as Chimera\, Pegasus and Zephyr. These architectures im pose finite connectivity and embedding constraints that strongly influence how correlations propagate and how metastable states are organized. Using the Fortuin–Kasteleyn–Coniglio–Klein (FKCK) cluster framework\, I s how that even in the absence of a conventional finite-temperature spin-gla ss transition\, frustration and disorder generate multiple dynamical time scales. The emergence and fragmentation of large-scale clusters provide a geometric interpretation of slow relaxation and reveal how topology contro ls the onset of collective dynamics. This perspective offers a physically transparent way to characterize energy landscapes on realistic annealing h ardware and provides quantitative insight into how graph connectivity and frustration jointly determine the performance and limitations of quantum a nnealing architectures.\n\nhttps://fisindico.uniandes.edu.co/event/23/cont ributions/327/ LOCATION:Universidad de los Andes ML-513 URL:https://fisindico.uniandes.edu.co/event/23/contributions/327/ END:VEVENT BEGIN:VEVENT SUMMARY:Inducing synchronization in complex networks via stochastic resett ing in the Kuramoto model DTSTART;VALUE=DATE-TIME:20260414T220400Z DTEND;VALUE=DATE-TIME:20260414T221100Z DTSTAMP;VALUE=DATE-TIME:20261017T094951Z UID:indico-contribution-23-330@fisindico.uniandes.edu.co DESCRIPTION:Speakers: KEVIN PARAMERO ARIAS (UNIVERSIDAD NACIONAL DE COLOMB IA)\nCollective synchronization is an emergent phenomenon in physical\, bi ological\, and\ntechnological systems\, where local interactions enable dy namical adjustment among\noscillators. In complex networks\, the Kuramoto model provides a fundamental framework to study the transition between inc oherent and synchronized states\; however\, synchronization typically requ ires sufficiently strong coupling\, which limits its controllability in su bcritical regimes. In this work\, we investigate an extension based on the stochastic resetting of subsystems\, defined as random interruptions that restore the phase of a fraction of nodes to a reference value. We analyze this dynamics on different network topologies using numerical simulations and a mean-field theoretical approach\, evaluating the role of the resett ing rate\, the fraction of reset nodes\, and structural heterogeneity in t he synchronization transition. \nOur main result shows that stochastic res etting can induce synchronization even in regimes where the original dynam ics remains incoherent. This mechanism acts as a local realignment process that counteracts phase dispersion and reduces the effective coupling thre shold. These findings identify resetting as an effective strategy to promo te and control collective coherence in complex oscillator networks.\n\nhtt ps://fisindico.uniandes.edu.co/event/23/contributions/330/ LOCATION:Universidad Nacional Edificio 564 URL:https://fisindico.uniandes.edu.co/event/23/contributions/330/ END:VEVENT BEGIN:VEVENT SUMMARY:Dynamics of correlations in a Werner state weakly coupled to a the rmal bath DTSTART;VALUE=DATE-TIME:20260414T221100Z DTEND;VALUE=DATE-TIME:20260414T221800Z DTSTAMP;VALUE=DATE-TIME:20261017T094951Z UID:indico-contribution-23-332@fisindico.uniandes.edu.co DESCRIPTION:Speakers: Daniel Felipe Vargas Castillo (Universidad de los An des)\nQuantum thermodynamics aims to understand how thermodynamic processe s emerge in quantum systems\, particularly in relation to information and entanglement. In this work we study the dynamics of correlations of a Wern er state composed of two qubits weakly coupled to a thermal bath. The syst em is described using a Lindblad master equation\, modelling the environme nt as a thermal reservoir that induces transitions between the qubit energ y levels according to Boltzmann statistics. Within this framework we analy ze the evolution of thermodynamic and informational quantities\, such as e ntropy and mutual information\, as functions of temperature and of the Wer ner-state parameter. Finally\, we discuss mechanisms governing the transfo rmation between different Werner states and the thermodynamic aspects asso ciated with these changes.\n\nhttps://fisindico.uniandes.edu.co/event/23/c ontributions/332/ LOCATION:Universidad Nacional Edificio 564 URL:https://fisindico.uniandes.edu.co/event/23/contributions/332/ END:VEVENT BEGIN:VEVENT SUMMARY:Active Paths and Effective Stochastic Dynamics in Small Neural Net works DTSTART;VALUE=DATE-TIME:20260414T230700Z DTEND;VALUE=DATE-TIME:20260414T231400Z DTSTAMP;VALUE=DATE-TIME:20261017T094951Z UID:indico-contribution-23-344@fisindico.uniandes.edu.co DESCRIPTION:Speakers: Cristian Pena ()\nThis project proposes to study a s mall neural network trained on a simple supervised learning task from a pe rspective inspired by statistical mechanics. The central idea is to identi fy the active paths connecting the input and output layers\, analyze how t hey contribute to the represented function before and after training\, and investigate whether their collective behavior admits an effective macrosc opic description. To do this\, the network output will be decomposed into contributions associated with active paths\, and several collective observ ables will be introduced\, including the number of active paths\, the dist ribution of their effective contributions\, and their temporal evolution d uring learning. Using multiple random initializations and training traject ories under stochastic gradient descent\, the project will examine whether the evolution of the learned output can be approximated by an effective s tochastic differential equation of the form $df_t(x)=A_t(x)\,dt + B_t(x)\, dW_t$\, where $A_t(x)$ represents an average learning drift and $B_t(x)$ a fluctuation term induced by the stochastic nature of training. The main g oal is to explore whether active paths can be interpreted as mesoscopic va riables linking the microscopic dynamics of the weights with the macroscop ic evolution of the learned function\, providing a more structured descrip tion of supervised learning.\n\nhttps://fisindico.uniandes.edu.co/event/23 /contributions/344/ LOCATION:Universidad Nacional Edificio 564 URL:https://fisindico.uniandes.edu.co/event/23/contributions/344/ END:VEVENT BEGIN:VEVENT SUMMARY:Field-theoretic Formulation of Ion Correlations with Explicit Hard -Core Size in Aqueous and Non-Aqueous Electrolytes DTSTART;VALUE=DATE-TIME:20260417T161000Z DTEND;VALUE=DATE-TIME:20260417T163000Z DTSTAMP;VALUE=DATE-TIME:20261017T094951Z UID:indico-contribution-23-331@fisindico.uniandes.edu.co DESCRIPTION:Speakers: Sahin Buyukdagli (Associate Professor\, Bilkent Univ ersity)\nThe accurate formulation of ion correlations in charged solutions is a critical task for the control of various biological and industrial p rocesses ranging from ion transport through cells to water purification pr ocedures. The theoretical tools enabling the comprehension of these system s is based on the Debye-Hückel (DH) theory suffering from major limitatio ns [1]. Namely\, the validity of the DH formalism neglecting the ionic har d-core (HC) size and including exclusively electrostatic weak-coupling-lev el ion correlations is limited to the characterization of monovalent salts at dilute concentrations.\n\nIn this talk\, I will present an ion size-au gmented self-consistent DH (SCDH) theory of bulk electrolytes exploiting t he asymmetric incorporation of the short- and long-range ion interactions via their virial and cumulant-level treatment\, respectively [2\,3]. The u nderlying variational splitting of the distinct interaction ranges enables the accurate prediction of ionic activity coefficients\,\ninternal energi es\, osmotic pressures\, and radial distribution functions of aqueous and non-aqueous electrolytes up to molar salt concentrations. \n\n[1] P. Debye and E. Hückel\, "The theory of electrolytes. I. Lowering of freezing poi nt and related phenomena"\, Zur Theorie der Elektrolyte. Phys. Z. 24\, 185 (1923).\n[2] S. Buyukdagli\, "Self-consistent electrostatic formalism of bulk electrolytes based on the asymmetric treatment of the short- and long -range ion interactions"\, Soft Matter 20\, 9104 (2024).\n[3] S. Buyukdagl i\, "Unified theory of equilibrium thermodynamics and ion association in a queous and non-aqueous electrolytes with explicit hard-core size"\, J. Che m. Theory Comput. 22\, 831 (2026).\n\nhttps://fisindico.uniandes.edu.co/ev ent/23/contributions/331/ LOCATION: URL:https://fisindico.uniandes.edu.co/event/23/contributions/331/ END:VEVENT BEGIN:VEVENT SUMMARY:Defect-induced ferroic states in solid solutions of layered van de r Waals DTSTART;VALUE=DATE-TIME:20260416T161000Z DTEND;VALUE=DATE-TIME:20260416T163000Z DTSTAMP;VALUE=DATE-TIME:20261017T094951Z UID:indico-contribution-23-322@fisindico.uniandes.edu.co DESCRIPTION:Speakers: Paula Giraldo Gallo (Universidad de los Andes)\nSoli d solutions of transition-metal dichalcogenides (TMDs)\, a family of cuasi -2D van der Waals materials\, provide a powerful platform to explore how c omposition\, structural symmetry\, and defect chemistry collectively deter mine electronic and ferroic properties in layered materials. In particular \, the ability to independently tune substitutional disorder and intrinsic defect populations offers a route to stabilize emergent phases that are a bsent in stoichiometric compounds. These materials therefore offer a versa tile framework to investigate how compositional engineering and defect-med iated symmetry breaking can generate new functional states.\n\nIn this tal k\, I will discuss how alloying different TMDs can be a general strategy t o control structural symmetry and electronic instabilities that give rise to multiple ferroic orders. Within this framework\, chemical substitution primarily modifies lattice parameters\, bonding geometry\, and spin–orbi t coupling\, while deviations from ideal stoichiometry introduce defect po pulations that can locally break inversion symmetry and generate magnetic moments or electric dipoles. The interplay between these two control param eters provides a pathway to stabilize magnetic\, polar\, and multiferroic states in otherwise non-ferroic layered materials.\n\nI will illustrate th ese ideas with experimental examples from the alloy families WSe2-WTe2 and WS2-WTe2\, synthesized as bulk single crystals and characterized through structural\, magnetic\, piezoresponse and transport measurements. In parti cular\, the WSe2-WTe2 system reveals a systematic evolution of lattice sym metry and unit cell volume with tellurium substitution and the emergence o f defect-stabilized magnetic and polar responses as the chalcogen vacancy density increases. By correlating substitution and defect concentration\, a configurational ferroic phase diagram can be constructed that separates paramagnetic–ferromagnetic\, paraelectric-ferroelectric\, and multiferro ic regimes. These results highlight how solid-solution engineering in laye red van der Waals materials provides a general route to stabilize emergent ferroic phases through the coupled control of composition and defects.\n\ nhttps://fisindico.uniandes.edu.co/event/23/contributions/322/ LOCATION:Universidad de los Andes ML-513 URL:https://fisindico.uniandes.edu.co/event/23/contributions/322/ END:VEVENT BEGIN:VEVENT SUMMARY:Decoherence-assisted quantum key distribution DTSTART;VALUE=DATE-TIME:20260417T201000Z DTEND;VALUE=DATE-TIME:20260417T203000Z DTSTAMP;VALUE=DATE-TIME:20261017T094951Z UID:indico-contribution-23-321@fisindico.uniandes.edu.co DESCRIPTION:Speakers: Alejandra Valencia (Universidad de los Andes)\nIn th e development of quantum technologies\, the interaction between a quantum system and its environment\, that leads to decoherence\, is traditionally viewed as a fundamental obstacle. In Quantum Key Distribution (QKD) protoc ols like BB84\, environmental noise inevitably degrades state purity\, inc reases the Quantum Bit Error Rate (QBER)\, and ultimately compromises the security of the communication channel. \n\nIn this talk\, we challenge thi s standard paradigm by presenting a theoretical and experimental study of a controllable decoherence-assisted QKD scheme [1]. Rather than attempting to isolate the quantum system from environmental noise\, we demonstrate h ow decoherence can be actively harnessed as a tool to enhance security aga inst specific eavesdropping strategies\, such as the entangling probe atta ck.\n \nWe will discuss our method of introducing tunable decoherence to p olarization qubits by coupling them to the spatial degree of freedom of li ght. By treating the transverse \nmomentum of the light as a controllable environment\, the sender and receiver (Alice and Bob) can dynamically coor dinate and vary the induced dephasing during transmission. When incorporat ed into a modified key reconciliation stage\, this shared\, controlled dec oherence effectively limits the amount of information an eavesdropper \nca n extract.\n\nFinally\, we will share the results of our experimental impl ementation\, demonstrating that Alice and Bob can cancel out the dephasing effects to recover a low QBER of approximately 7.38%. Ultimately\, this w ork adds to the effort of a different perspective on open quantum systems: proving that system-environment interactions can be strategically managed to our advantage rather than merely mitigated. \n\n[1] Sci. Rep. 15\, 312 58 (2025).\n\nhttps://fisindico.uniandes.edu.co/event/23/contributions/321 / LOCATION:Universidad de los Andes ML-513 URL:https://fisindico.uniandes.edu.co/event/23/contributions/321/ END:VEVENT BEGIN:VEVENT SUMMARY:Scale invariance in heavy tails of the S&P 500 stock index using t he fractional Laskin model DTSTART;VALUE=DATE-TIME:20260414T221800Z DTEND;VALUE=DATE-TIME:20260414T222500Z DTSTAMP;VALUE=DATE-TIME:20261017T094951Z UID:indico-contribution-23-333@fisindico.uniandes.edu.co DESCRIPTION:Speakers: Oscar Fabio Herrera Marroquín (universidad nacion al de Colombia)\nIn this work\, we study the time scale invariance for the heavy tails of the minute log returns time series of the S&P 500 stock in dex for three different time periods (January 2011 – October 2015\, Nove mber 2015 – December 2019\, January 2020 – October 2023)\, considering minute\, hour\, and day time series for each case. Using the symmetric fr actional Laskin model\, which describes the dissipative effects of the fin ancial market through a shot noise type stochastic dissipative force that is similar for positive and negative log returns\, we calculate the fittin g parameters of the heavy tails for each of the considered time periods an d for each of the studied time scales. We contrast these fitting parameter s with the power law exponents calculated for the high log returns time se ries (data above a certain threshold)\, for both positive and negative log returns\, showing the existence of asymmetry for each of the cases. The a symmetries found in the heavy tails are consistent with those observed thr ough the Lévy distribution fitting parameters of the low and medium time series log returns.\n\nhttps://fisindico.uniandes.edu.co/event/23/contribu tions/333/ LOCATION:Universidad Nacional Edificio 564 URL:https://fisindico.uniandes.edu.co/event/23/contributions/333/ END:VEVENT BEGIN:VEVENT SUMMARY:Structural and magnetic characterization of $Pr_{0.5}Ca_{0.09}Sr_{ 0.41}MnO_3$ manganites DTSTART;VALUE=DATE-TIME:20260414T231300Z DTEND;VALUE=DATE-TIME:20260414T232000Z DTSTAMP;VALUE=DATE-TIME:20261017T094951Z UID:indico-contribution-23-357@fisindico.uniandes.edu.co DESCRIPTION:Speakers: Gabriela Rodriguez (Los Andes University)\nManganite s with a $CaMnO_3$-type structure are generally antiferromagnetic and insu lating at low temperatures. However\, chemical substitution with rare-eart h elements induces strong competition between coexisting antiferromagnetic (AFM) and ferromagnetic (FM) phases\, often leading to phase separation a nd field-induced metamagnetic transitions. These transitions can be unders tood as percolation events\, where FM metallic clusters grow within an AFM insulating matrix until a conducting network spans the system at the perc olation threshold\, driving the metal-insulator transition. Despite extens ive research\, the coupling between structural distortions and magnetic or dering in these systems remains not fully understood.\n\nHere\, we present a structural and compositional characterization of $Pr_{0.5}Ca_{0.09}Sr_ {0.41}MnO_3$ (PCSMO) powder. The crystal structure and phase purity were examined by X-ray diffraction (XRD) and Raman spectroscopy\, while the el emental composition was analyzed using energy-dispersive X-ray spectroscop y (EDX). Magnetic characterization was done through vibrating sample magne tometry (VSM) measurements performed at different temperatures to evaluate magnetic transitions. Our results suggest potential applications in neuro morphic computing as well as in magnetic and thermal sensing devices.\n\nh ttps://fisindico.uniandes.edu.co/event/23/contributions/357/ LOCATION:Universidad Nacional Edificio 564 URL:https://fisindico.uniandes.edu.co/event/23/contributions/357/ END:VEVENT BEGIN:VEVENT SUMMARY:Scaling of ensemble fluctuation and Pareto laws in the distributio ns of average property prices per block in Bogotá DTSTART;VALUE=DATE-TIME:20260414T222500Z DTEND;VALUE=DATE-TIME:20260414T223200Z DTSTAMP;VALUE=DATE-TIME:20261017T094951Z UID:indico-contribution-23-334@fisindico.uniandes.edu.co DESCRIPTION:Speakers: Esteban Quintero Martinez (Universidad Nacional de C olombia)\nAn econophysical study of datasets on cadastral and commercial v alues of average prices per property per block in Bogotá leads us to iden tify the existence of ensemble fluctuation scaling. This scaling\, which i s a property of complex systems observed in a variety of natural scenarios and is characterized by a power-law relationship between the variance and the mean of the data\, is found for the first time in data on average urb an property prices. Furthermore\, we find that the scaling of ensemble flu ctuations exhibit spatial scale invariance when considering average proper ty prices per block at the following spatial scales: blocks\, neighborhood s\, zoning planning units\, and localities. Finally\, for low and medium a verage price values\, we find that the probability distribution fits a log normal distribution\, while the distribution above a certain price thresho ld follows a Pareto law for heavy tails.\n\nhttps://fisindico.uniandes.edu .co/event/23/contributions/334/ LOCATION:Universidad Nacional Edificio 564 URL:https://fisindico.uniandes.edu.co/event/23/contributions/334/ END:VEVENT BEGIN:VEVENT SUMMARY:Disordered systems out of equilibrium DTSTART;VALUE=DATE-TIME:20260413T140000Z DTEND;VALUE=DATE-TIME:20260413T153000Z DTSTAMP;VALUE=DATE-TIME:20261017T094951Z UID:indico-contribution-23-353@fisindico.uniandes.edu.co DESCRIPTION:Speakers: Leticia F. Cugliandolo (Sorbonne Université\, Paris )\n1. Introduction. Quenched and configurational disorder. Coarsening. Gla ssiness and active matter. Models and methods.\n2. Equilibrium analysis. F ree-energy landscapes (extensions of Ginzburg-Landau).\n3. Out of equilibr ium dynamics. Dynamic mean-field theory.\n\nhttps://fisindico.uniandes.edu .co/event/23/contributions/353/ LOCATION:Universidad Nacional de Colombia Ed. 564 URL:https://fisindico.uniandes.edu.co/event/23/contributions/353/ END:VEVENT BEGIN:VEVENT SUMMARY:Thermostatistical study of the opinion formation phenomenon in the DNAW model DTSTART;VALUE=DATE-TIME:20260413T214000Z DTEND;VALUE=DATE-TIME:20260413T220000Z DTSTAMP;VALUE=DATE-TIME:20261017T094951Z UID:indico-contribution-23-335@fisindico.uniandes.edu.co DESCRIPTION:Speakers: Jefferson Rubiano Forero (Universidad Nacional DE Co lombia)\nThe model proposed by Default\, Neau\, Amblard\, and Weisbuch (DN AW) is relevant in sociophysics for studying the phenomenon of opinion for mation in social systems composed of agents that interact in a binary mann er. Its relevance lies in the fact that\, through the formulation of an op inion exchange rule between pairs of agents whose opinion differences are smaller than a bounded confidence threshold (d)\, and which is expressed i n terms of a convergence parameter (μ)\, it is possible to reproduce coll ective phenomena observed in social systems such as consensus\, fragmentat ion\, and polarization. Within the framework of this model\, by establishi ng an analogy between a system of social agents and an ideal gas of free p articles\, we present a novel thermostatistical study of the opinion forma tion phenomenon based on the definition of the following macroscopic varia bles: social temperature (Ts)\, social entropy (Ss)\, and social chemical potential (Ps). In particular\, we define Ts as the first absolute moment of the opinions of all agents in the system with respect to the average op inion (Op) per agent. Through numerical simulations that systematically ex plore the parameter space (d\, μ)\, we first identify the equilibrium sta te as the state for which Ss stabilizes and estimate the convergence time as the elapsed time required to reach equilibrium. Subsequently\, we study the opinion formation process by analyzing the temporal evolution of the macroscopic variables Op\, Ts\, Ss\, and Ps. In this way\, we observe that d can be interpreted as a measure of social tolerance to interact with di ffering opinions\, while μ quantifies the degree of mutual influence betw een a pair of agents during an interaction.\n\nhttps://fisindico.uniandes. edu.co/event/23/contributions/335/ LOCATION:Universidad Nacional Ed. 564 URL:https://fisindico.uniandes.edu.co/event/23/contributions/335/ END:VEVENT BEGIN:VEVENT SUMMARY:Random Walks on Networks: Effective Distance\, Entropy\, and Fract ional Dynamics DTSTART;VALUE=DATE-TIME:20260414T223200Z DTEND;VALUE=DATE-TIME:20260414T223900Z DTSTAMP;VALUE=DATE-TIME:20261017T094951Z UID:indico-contribution-23-336@fisindico.uniandes.edu.co DESCRIPTION:Speakers: Juan Pablo Castro Rodriguez (Universidad Nacional de Colombia)\nWe develop a path-integral formulation of first-passage random walks on networks and extend it to fractional transport dynamics. In this framework\, the random-walk effective distance is defined from the ensemb le of all first-passage trajectories connecting a source to a target\, wei ghted by both their probabilities and their lengths. This construction nat urally introduces a trajectory partition function\, an effective action\, and a free-energy-like interpretation of transport on networks. We further define the Shannon entropy of the first-passage trajectory ensemble and n ode-level indicators based on total shortest-path and total random-walk ef fective distances.\n\nThe formalism is first analyzed in simple benchmark topologies\, where it captures symmetry\, boundary effects\, hub dominance \, and hierarchy. It is then generalized to the fractional case by replaci ng local random-walk dynamics with nonlocal transport induced by the fract ional network operator. The results show that fractional dynamics reshapes effective distances\, trajectory diversity\, and node accessibility by en hancing long-range exploration across the network. Altogether\, the framew ork provides a unified description of local and nonlocal spreading on netw orks and offers a basis for future applications to complex systems.\n\nhtt ps://fisindico.uniandes.edu.co/event/23/contributions/336/ LOCATION:Universidad Nacional Edificio 564 URL:https://fisindico.uniandes.edu.co/event/23/contributions/336/ END:VEVENT BEGIN:VEVENT SUMMARY:Stability of Nonrelativistic Matter DTSTART;VALUE=DATE-TIME:20260414T223900Z DTEND;VALUE=DATE-TIME:20260414T224600Z DTSTAMP;VALUE=DATE-TIME:20261017T094951Z UID:indico-contribution-23-337@fisindico.uniandes.edu.co DESCRIPTION:Speakers: Juan Felipe Prieto Mateus (Universidad de los Andes) \nThe stability of matter is often assumed without question. We typically believe that established physical theories can easily predict that atoms a nd molecules will not collapse or that the total energy of matter scales l inearly with the number of particles. However\, these questions remained u nresolved when quantum theory was first established\, and it actually took several decades before any proof was provided. In this talk\, we present Lieb's proof of the stability of non-relativistic matter. By modeling matt er as a system of $N$ particles interacting under Coulomb forces\, we show how to derive a linear bound for the total energy of the system as a func tion of $N$\; that is\, to find a constant $k$ such that $\\mathcal{E}(\\p si) > kN $ for every wave function $ \\psi $ of the system. To achieve thi s\, we apply the Lieb-Thirring inequalities in the context of Schrödinger operators and use a semiclassical approximation of the Coulomb energy. Fi nally\, we discuss how this linear bound for the total energy leads to the conclusion that matter is extensive and bosonic matter is unstable.\n\nht tps://fisindico.uniandes.edu.co/event/23/contributions/337/ LOCATION:Universidad Nacional Edificio 564 URL:https://fisindico.uniandes.edu.co/event/23/contributions/337/ END:VEVENT BEGIN:VEVENT SUMMARY:Entanglement and dynamical scaling laws in quantum superabsorptio n DTSTART;VALUE=DATE-TIME:20260417T193000Z DTEND;VALUE=DATE-TIME:20260417T195000Z DTSTAMP;VALUE=DATE-TIME:20261017T094951Z UID:indico-contribution-23-359@fisindico.uniandes.edu.co DESCRIPTION:Speakers: John Henry Reina (Universidad del Valle)\nIn this ta lk\, we explore the superabsorption effect in quantum batteries\, which ex ploit collective quantum resources to surpass the limits of classical ener gy storage and power delivery. We analyse N-qubit cavity-coupled quantum b atteries governed by Dicke and Tavis-Cummings models under Gaussian drivin g and open-system dynamics. Finite-size scaling laws $O(N) \\sim N^\\alpha $ demonstrate an optimal region of relaxation and dephasing in which coher ent driving stabilises entanglement entropy growth for thermodynamic obser vables (maximum energy Emax\, charging time τ\, and maximum power Pmax) a nd for qubit and cavity entanglement entropies. The Dicke model exhibits e ntropy-suppressed extensive behaviour\, while the Tavis-Cummings model ach ieves super-extensive scaling ($\\alpha_{\\text{Emax}} \\in [1.08\,1.26]$\ , $\\alpha_T \\simeq −0.49$\, $\\alpha_{\\text{Pmax}}\\in [1.57\,1.73]$) \, supported by qubit-cavity entanglement. \n\nWe demonstrate that dissipa tion can act as a stabiliser source\, yielding scaling benchmarks relevant to several experimental platforms. Our findings connect entanglement\, di ssipation-enhanced scaling laws\, and superabsorption\, outlining a pathwa y towards scalable quantum batteries that offer practical quantum advantag e.\n\nWork in collaboration with Juan D. Álvarez\n\nhttps://fisindico.un iandes.edu.co/event/23/contributions/359/ LOCATION:Universidad de los Andes ML-513 URL:https://fisindico.uniandes.edu.co/event/23/contributions/359/ END:VEVENT BEGIN:VEVENT SUMMARY:A statistical physics perspective on the theory of machine learnin g DTSTART;VALUE=DATE-TIME:20260415T133000Z DTEND;VALUE=DATE-TIME:20260415T150000Z DTSTAMP;VALUE=DATE-TIME:20261017T094951Z UID:indico-contribution-23-355@fisindico.uniandes.edu.co DESCRIPTION:Speakers: Bruno Loureiro (ENS Paris)\nThe past decade has witn essed a surge in the development and adoption of machine learning algorith ms to solve day-a-day computational tasks. Yet\, a solid theoretical under standing of even the most basic tools used in practice is still lacking\, as traditional statistical learning methods are unfit to deal with the mod ern regime in which the number of model parameters are of the same order a s the quantity of data – a problem known as the curse of dimensionality. Curiously\, this is precisely the regime studied by Physicists since the mid 19th century in the context of interacting many-particle systems. This connection\, which was first established in the seminal work of Elisabeth Gardner and Bernard Derrida in the 80s\, is the basis of a long and fruit ful marriage between these two fields.\n\nThe goal of this mini-course is to provide an in-depth overview of these connections and a good vision of the different tools available in the statistical physics toolbox\, as well as their scope and limitations. \n\nSyllabus:\n\n- Historical overview of the connections between Statistical Physics and Computer Science.\n- Mean -Field Models 101: Curie-Weiss Model\n- Statistical-to-Computational Gaps\ n- The double-descent phenomena and benign overfitting (time permitting)\n \nBibliography:\n\nThe mini-course will the based on the following lecture s notes: https://brloureiro.github.io/assets/pdf/NotesPrinceton_BL.pdf\n\n https://fisindico.uniandes.edu.co/event/23/contributions/355/ LOCATION:Universidad Nacional Ed. 564 URL:https://fisindico.uniandes.edu.co/event/23/contributions/355/ END:VEVENT BEGIN:VEVENT SUMMARY:Non-Extensive Statistical Mechanics and Heavy Tails in Financial L og-Returns: Stocks\, FX\, and Cryptocurrencies DTSTART;VALUE=DATE-TIME:20260414T224600Z DTEND;VALUE=DATE-TIME:20260414T225300Z DTSTAMP;VALUE=DATE-TIME:20261017T094951Z UID:indico-contribution-23-340@fisindico.uniandes.edu.co DESCRIPTION:Speakers: Juan Diego Rueda Mantilla (Universidad Nacional de C olombia)\nNon-extensive statistical mechanics\, introduced by Tsallis\, pr ovides a robust theoretical framework for describing complex systems chara cterized by long-range correlations and extreme events. In the context of financial markets\, the q-Gaussian distributions that emerge from this for malism constitute a natural generalization of Gaussian approaches\, as the y are capable of capturing the heavy tails that characterize empirical log -returns\, which standard Gaussian models fail to reproduce. In this work\ , we present a comprehensive empirical validation of a hybrid model that i ntegrates non-extensive statistical mechanics with a microscopic agent-bas ed dynamics characterized by herding behavior. The simulated log-returns a re compared with high-frequency data from stocks in developed and emerging markets\, revealing that the q-Gaussian model reproduces the heavy tails of liquid markets with remarkable accuracy\, whereas the Gaussian model be tter captures the statistical structure of assets such as oil and exchange rates\, additionally exhibiting a surprising degree of temporal scale inv ariance. An additional finding is the identification of an intrinsic limit to the validity of the hybrid model\, arising from its own dynamics witho ut the need for externally imposed criteria. The analysis is further exten ded to high-frequency cryptocurrency and foreign exchange pairs\, where th e systematic variation of the parameter q enables the quantification of th e degree of non-extensivity inherent to each market. The results indicate that the Tsallis formalism not only successfully captures the heavy tails of the assets considered\, but also that the parameter q serves as a quant itative indicator of the degree of statistical complexity inherent in each asset class\, raising the question of the potential universality of this approach across financial markets as diverse as digital and traditional on es.\n\nhttps://fisindico.uniandes.edu.co/event/23/contributions/340/ LOCATION:Universidad Nacional Edificio 564 URL:https://fisindico.uniandes.edu.co/event/23/contributions/340/ END:VEVENT BEGIN:VEVENT SUMMARY:Scaling Laws and Spectra of Shallow Neural Networks in the Feature -Learning Regime DTSTART;VALUE=DATE-TIME:20260416T210000Z DTEND;VALUE=DATE-TIME:20260416T213000Z DTSTAMP;VALUE=DATE-TIME:20261017T094951Z UID:indico-contribution-23-358@fisindico.uniandes.edu.co DESCRIPTION:Speakers: Bruno Loureiro (ENS Paris)\nNeural scaling laws unde rlie many of the recent advances in deep learning\, yet their theoretical understanding remains largely confined to linear models. In this work\, we present a systematic analysis of scaling laws for quadratic and diagonal neural networks in the feature learning regime. Leveraging connections wit h matrix compressed sensing and LASSO\, we derive a detailed phase diagram for the scaling exponents of the excess risk as a function of sample comp lexity and weight decay. This analysis uncovers crossovers between distinc t scaling regimes and plateau behaviours\, mirroring phenomena widely repo rted in the empirical neural scaling literature. Furthermore\, we establis h a precise link between these regimes and the spectral properties of the trained network weights\, which we characterize in detail. Consequently\, we provide a theoretical validation of recent empirical observations conne cting the emergence of power-law tails in the weight spectrum with network generalization performance\, yielding an interpretation from first princi ples.\n\nhttps://arxiv.org/abs/2509.24882\n\nhttps://fisindico.uniandes.ed u.co/event/23/contributions/358/ LOCATION:Universidad de los Andes ML-513 URL:https://fisindico.uniandes.edu.co/event/23/contributions/358/ END:VEVENT BEGIN:VEVENT SUMMARY:Topological Edge States and Nonequilibrium Quantum Transport in On e-Dimensional Topological Models: A Green's Function Approach DTSTART;VALUE=DATE-TIME:20260414T225300Z DTEND;VALUE=DATE-TIME:20260414T230000Z DTSTAMP;VALUE=DATE-TIME:20261017T094951Z UID:indico-contribution-23-341@fisindico.uniandes.edu.co DESCRIPTION:Speakers: Juan José Mayorga Bonilla (Universidad Nacional de Colombia)\nThis work presents an analytical Green's function study of one- dimensional topological models aimed at connecting their equilibrium spect ral properties to nonequilibrium quantum transport. Working in the continu um limit\, we derive exact expressions for the retarded Green's function o f the bulk\, the semi-infinite chain\, and the finite chain\, computing th e Local Density of States (LDOS) in each geometry and tracing the progress ive emergence of topologically protected boundary states\, which are absen t in the bulk spectrum. By this framework\, we model a two-terminal juncti on consisting of a finite topological chain contacted by two normal metall ic leads and using the Keldysh Non-Equilibrium Green Function formalism\, we compute the transmission function and analyze the nonequilibrium transp ort properties of the junction. This work provides a fully analytical and unified framework connecting bulk topology\, boundary spectral properties\ , and out-of-equilibrium current statistics in topological junctions.\n\nh ttps://fisindico.uniandes.edu.co/event/23/contributions/341/ LOCATION:Universidad Nacional Edificio 564 URL:https://fisindico.uniandes.edu.co/event/23/contributions/341/ END:VEVENT BEGIN:VEVENT SUMMARY:Monte Carlo modeling of asphalt surface wear under studded-tire tr affic DTSTART;VALUE=DATE-TIME:20260417T153000Z DTEND;VALUE=DATE-TIME:20260417T155000Z DTSTAMP;VALUE=DATE-TIME:20261017T094951Z UID:indico-contribution-23-307@fisindico.uniandes.edu.co DESCRIPTION:Speakers: Dayani Loaiza Monsalve (Laval University)\nThis stud y investigates the evolution of asphalt pavement surface damage caused by studded-tire traffic using a combined experimental and stochastic modeling approach. Laboratory tests on six asphalt mixtures were integrated into a Monte Carlo simulation framework that models rutting as the cumulative ef fect of random stud impacts. The model incorporates parameters describing cumulative damage\, particle detachment energy thresholds\, and material s usceptibility to wear. The simulations successfully reproduce the transiti on from an initial nonlinear damage phase to a stabilized linear rutting r egime observed experimentally. A strong linear relationship was identified between the stochastic detachment parameter\, the laboratory rutting rate \, and the abrasion resistance of the mixtures. These results confirm the model’s capacity to reproduce measurable material behavior. By linking m ixture characteristics to probabilistic descriptions of surface deteriorat ion\, the proposed framework provides a predictive tool to support the des ign of more wear-resistant pavements in cold-climate regions.\n\nhttps://f isindico.uniandes.edu.co/event/23/contributions/307/ LOCATION:Universidad de los Andes URL:https://fisindico.uniandes.edu.co/event/23/contributions/307/ END:VEVENT BEGIN:VEVENT SUMMARY:Fast thermal equilibration using machine learning DTSTART;VALUE=DATE-TIME:20260413T164000Z DTEND;VALUE=DATE-TIME:20260413T170000Z DTSTAMP;VALUE=DATE-TIME:20261017T094951Z UID:indico-contribution-23-342@fisindico.uniandes.edu.co DESCRIPTION:Speakers: Diego Rengifo (Technical University Berlin )\nFast t hermal equilibration\, also known as a shortcut to adiabaticity\, is an ex ternal control technique employed to expedite operations beyond the system ’s natural timescale. In this talk\, we will introduce a machine learnin g technique\, specifically automatic differentiation\, to identify control protocols that accelerate the equilibration process in stochastic systems modeled by the overdamped Langevin equation.\n\nhttps://fisindico.uniande s.edu.co/event/23/contributions/342/ LOCATION:Universidad Nacional de Colombia Ed. 564 URL:https://fisindico.uniandes.edu.co/event/23/contributions/342/ END:VEVENT BEGIN:VEVENT SUMMARY:Two-Point Correlation in Dyson Gases Out-of-Equilibrum DTSTART;VALUE=DATE-TIME:20260417T163000Z DTEND;VALUE=DATE-TIME:20260417T165000Z DTSTAMP;VALUE=DATE-TIME:20261017T094951Z UID:indico-contribution-23-343@fisindico.uniandes.edu.co DESCRIPTION:Speakers: John Fredy Mateus Rubio (Universidad de los Andes)\n We study the dynamics of a Log-Coulomb gas consisting of N charged particl es confined to a unitary circle and coupled to a thermal bath characterize d by a dimensionless effective parameter $\\beta = q_0^2/(k_BT)$ with $q_0 $ the charge per particle\, $T$ the bath temperature\, and $k_B$ the Boltz mann’s constant. The use of a circular domain eliminates boundary effect s and ensures exact rotational invariance\, leading to an uniform equilibr ium density without external confinement. This geometry isolates universal collective properties and greatly simplifies both static and dynamical an alyses of logarithmic Coulomb gases particularly\, for $\\beta = 2$\, the system can be treated as a free-fermion model\, for which we can obtain an analytical expression for the two-point correlation function in the simpl est case $N = 2$\, and then extend our analysis to $N > 2$ both numericall y and analytically. By varying $\\beta$\, we show that a logarithmic time- law scaling governs the time evolution of this process\, and we verify the validity of the probability distribution of spacings between consecutive particles (levels)\, called Wigner’s surmise\, for $\\beta \\geq 1$ by c omparison with the corresponding Gaussian ensembles for times larger than the relaxation time\, $\\tau \\geq \\tau_{\\text{Eq}}$\, i.e.\, once the s ystem has reached thermal equilibrium.\n\nhttps://fisindico.uniandes.edu.c o/event/23/contributions/343/ LOCATION: URL:https://fisindico.uniandes.edu.co/event/23/contributions/343/ END:VEVENT BEGIN:VEVENT SUMMARY:Feedback control and the Second Law of thermodynamics in a ratchet physical system DTSTART;VALUE=DATE-TIME:20260416T215000Z DTEND;VALUE=DATE-TIME:20260416T221000Z DTSTAMP;VALUE=DATE-TIME:20261017T094951Z UID:indico-contribution-23-346@fisindico.uniandes.edu.co DESCRIPTION:Speakers: David Calderón Gómez (Universidad de los Andes)\nW e simulate a realization of Maxwell’s demon based on the experimental se tup developed in \\textit{Bayesian Information Engine that Optimally Explo its Noisy Measurements}\, in which a heavy bead\, immersed in water at roo m temperature\, is trapped by an optical tweezer and lifted through rapid feedback control without net work expenditure. This system functions as an information engine\, harnessing favorable thermal fluctuations to increas e the bead’s gravitational potential energy while keeping the trap’s p otential energy unchanged. Our simulations successfully reproduce key expe rimental findings regarding the engine’s performance across a range of n oisy measurements and verify the Generalized Jarzynski Inequality. In cont rast to previous works that employ a Langevin dynamics approach\, we imple ment a molecular dynamics algorithm to model the system. Our results confi rm that the Generalized Jarzynski Inequality holds for all tested cases\, by a significant margin. This study contributes to the theoretical underst anding of the thermodynamics of mesoscopic systems under feedback control and further reinforces the fundamental connection between information and thermodynamics.\n\nhttps://fisindico.uniandes.edu.co/event/23/contribution s/346/ LOCATION:Universidad de los Andes URL:https://fisindico.uniandes.edu.co/event/23/contributions/346/ END:VEVENT BEGIN:VEVENT SUMMARY:Modeling Invasion Percolation in Granular Media with Evolving Rheo logy: The Case of Rice Cooking. DTSTART;VALUE=DATE-TIME:20260414T231300Z DTEND;VALUE=DATE-TIME:20260414T232000Z DTSTAMP;VALUE=DATE-TIME:20261017T094951Z UID:indico-contribution-23-347@fisindico.uniandes.edu.co DESCRIPTION:Speakers: Braither Diaz ()\nThe rice cooking process represent s a complex physical system where phase transition thermodynamics\, biopol ymer leaching\, and granular media mechanics converge. In this work\, we p resent a cellular automaton model based on the Invasion Percolation (IP) a lgorithm to simulate the dynamics of nucleation and water vapor transport through a grain bed.Unlike standard IP models\, our approach incorporates a thermo-rheological coupling: the heat flux at the base induces a thermal gradient that governs starch gelatinization kinetics via an Arrhenius-typ e relationship. The subsequent leaching of amylose and amylopectin modifie s the viscosity of the continuous phase following the Quemada model\, lead ing to a viscosity divergence as the solvent is depleted. Simultaneously\, the mechanical transition of the grains is modeled through a critical inv asion radius ($R_c$)\, which discriminates between the physical displaceme nt of the grains (piston-like regime with geometric memory) and capillary flow (channeling).Preliminary results suggest that the competition between bubble buoyancy and the hardening of the polymeric gel defines the morpho logy of the vapor channels\, explaining the formation of the tubular struc tures ("rice holes") observed macroscopically during cooking. This model p rovides a framework to understand how local heterogeneities in friction an d dynamic surface tension dictate the final transport state in saturated g ranular systems.\n\nhttps://fisindico.uniandes.edu.co/event/23/contributio ns/347/ LOCATION:Universidad Nacional Edificio 564 URL:https://fisindico.uniandes.edu.co/event/23/contributions/347/ END:VEVENT BEGIN:VEVENT SUMMARY:Estudio Monte Carlo de la Entropía Residual en Redes de Ising Fru stradas DTSTART;VALUE=DATE-TIME:20260414T231300Z DTEND;VALUE=DATE-TIME:20260414T232000Z DTSTAMP;VALUE=DATE-TIME:20261017T094951Z UID:indico-contribution-23-348@fisindico.uniandes.edu.co DESCRIPTION:Speakers: Adriana María Velásquez Medina (Universidad de los Andes)\nEste trabajo analiza cómo las modificaciones topológicas afecta n la entropía residual y la degeneración del estado base en sistemas fru strados del modelo de Ising. Tomando como referencia las redes triangular y kagome antiferromagnéticas\, se emplea un enfoque computacional basado en simulaciones de Monte Carlo e integración termodinámica.\n\nSe estudi an tanto defectos aleatorios como modificaciones periódicas de la red. Lo s resultados muestran que la dilución de sitios y enlaces reduce la entro pía residual al aliviar la frustración\, mientras que las estructuras ti po stitched kagome permiten modificar la degeneración de forma controlada . Estos resultados muestran que la conectividad de la red modifica la dege neración del estado base y la entropía residual en estos sistemas.\n\nht tps://fisindico.uniandes.edu.co/event/23/contributions/348/ LOCATION:Universidad Nacional Edificio 564 URL:https://fisindico.uniandes.edu.co/event/23/contributions/348/ END:VEVENT END:VCALENDAR