Vol. 1 No. 4 (2020): Suplemento de la Revista Mexicana de Física. Homage to Prof. Germinal Cocho
Los participantes de este número especial dedicado al Profe Germi, al que pudiese catalogarse el Padre de las ciencias de la complejidad en México, hemos querido rendir este modesto homenaje. Nos pareció oportuno, que la mejor forma de rendirle un justo homenaje a Germi, era recoger de forma sucinta, los criterios y las vivencias de una serie de colegas y amigos, so pena de haber omitido alguno.
Guest Editors:
José Manuel Nieto Villar, Universidad de La Habana, Cuba.
Ricardo Mansilla, Centro de Investigaciones Interdisciplinarias en Ciencias y Humanidades, UNAM, México.
04 HOMENAJE AL DR. GERMINAL COCHO
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Preface
Abstract:El Prof. Germinal Cocho ha sido, no solo en México sino también en el resto del mundo, un paradigma de las Ciencias de la Complejidad. Como investigador y educador contribuyó notablemente a la formación de numerosas generaciones de científicos y a que la ciencia en México goce de un merecido prestigio.⬇️ Scroll down to see the full summary -
Logros en ciencias de la complejidad en el IFUNAM: una recopilación incompleta
Abstract:⬇️ Scroll down to see the full summaryA pesar de que la complejidad se suele considerar como un paradigma joven, que irrumpió hace poco en áreas muy diversas de la ciencia, la investigación en sistemas complejos tiene una larga tradición en México. Se inició en el Instituto de Física en los años 70 y Germinal Cocho fue un actor central de su desarrollo ahí y en la UNAM, a lo largo de cuatro décadas. Aquí presentamos una breve revisión, necesariamente incompleta, de logros obtenidos en varias áreas de la complejidad en el Instituto de Física por Germinal Cocho y sus numerosos colaboradores y colegas.
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Retarded hydrodynamic fluctuations effects on the light scattering spectrum and elastic moduli of a linear viscoelastic liquid
Abstract:Fluctuating hydrodynamics (FH) is one of the theories that describes the dynamics of the fluctuations for fluids at mesoscopic scales. However, it is only valid for Markovian processes. Here we extend this approach for a viscoelastic liquid by using a generalized Langevin equation (GLE). We obyain general analytic expressions for the density fluctuations correlation function, the dynamic structure factor and the light scattering spectrum. In particular, we calculate the intermediate scattering function when the time memory and the noise correlation function are power-laws. We find that the difference in values of this quantity as functions of the viscoelasticity may be ∼62% and might be measurable.⬇️ Scroll down to see the full summary -
¿Qué es la vida? 76 años después: una mirada desde la termodinámica y los sistemas complejos
Abstract:⬇️ Scroll down to see the full summarySe presenta una panorámica de los tópicos fundamentales del trabajo seminal de Schrödinger, ¿Qué es la vida?, Capítulos 6 y 7 respectivamente y se establece una análisis de los mismos desde el formalismo de la termodinámica de los procesos irreversibles y los sistemas complejos. De esta forma, se establecen una serie de consideraciones epistemológicas que evidencia la importancia y actualidad del mismo.
An overview of the fundamental topics of Schrödinger's seminal work, What is life? Chapters 6 and 7, respectively, and an analysis of them from the thermodynamic formalism of irreversible processes and complex systems is presented. In this way, a series of epistemological considerations have established that show its importance and timeliness.
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Una mirada a los sistemas complejos desde la termodinámica
Abstract:Se presenta una panorámica del formalismo termodinámico irreversible y su vinculación con los sistemas complejos. Se muestra como la velocidad de producción de entropía constituye per se una función natural de Lyapunov. Una extensión a los sistemas biofísico-químicos, evidenció como la velocidad de producción de entropía representa una vía magnitud física para medir la complejidad y la robustez del cáncer.⬇️ Scroll down to see the full summary -
Cancer metastasis and the immune system response: modeling the micro-environment by Ising hamiltonian
Abstract:⬇️ Scroll down to see the full summaryTo overcome the cancer seeding and late metastasis, the immune system opportune response is essential. Recently, the system biology approach is relevant for better understanding the highly complex process of cancer metastasis and the immune system response CM-IS. Diverse
mathematical modeling and algorithmic simulations has been introduced in the tumor immune research. In spite of that the comprehension is far away to be satisfactory. In this paper we introduce an Ising Hamiltonian energy function to model the micro-environment of CM-IS,
focus on the innate immune system response. -
A zodiac of studies on complex systems
Abstract:⬇️ Scroll down to see the full summaryWe offer a brief description of a set of interrelated research lines on the physics of complex systems developed under a unifying methodology grown out from nonlinear dynamics of low dimensionality. The research lines were, and are, developed over a two-decade period (tacitly or not) under a simplifying assumption (and a posteriori corroboration) of a drastic reduction of degrees of freedom. The studies are conveniently grouped into twelve units, and these in turn into four groups, as in a zodiac. The studies in the first group, named Sensitivities, Glasses and Localizations, have in common a clear-cut original opening in the sense that, to our knowledge, the main tenet or result is not found elsewhere. Those in the second group, named Sums, Rankings and Fluctuations, have as a starting point previous stimulating studies or ideas that we followed up but then we converted into separate approaches. The subjects in the third group, named Networks, Measures and Games, involve preset work programs to be followed but ended up within unanticipated, perhaps deeper, grounds. The topics in the final fourth group, named Partitions, Diagonals and Windows, occurred, or are taking place, as specific technical goals that have become after belated realizations to be possible contributions towards the answer of fundamental quests. We discuss connections underlying different aspects of these investigations. Nonlinear dynamics
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Stroboscopic observation of a random walker
Abstract:The patterns of motion of mobile agents have received recently wide attention in the literature. There is a number of recent studies centered around the motion behavior of many agents ranging from albatrosses to human beings. Special attention has been given to the covered distances statistical distributions. In some cases, due to the lack of accurate data about the motion of the agents it has been necessary to plan very clever experiments to obtain them. These experiments try to infer the statistical properties of the agents' real motion from the observed positions in consecutive time intervals. The length of the time intervals are random variables taking their values from a previously known statistical distribution or from a distribution deduced from empirical data. The aim of this work is to demonstrate that for a Gaussian Random Walker it is, in general, impossible to recover the real motion patterns distribution from the stroboscopic observation of the agents unless the length of the intervals between two consecutive measurements are equal. Moreover, it is also shown that the distances distribution strongly depends on the agents' observation time intervals. These claims are sustained by numerical experiments.⬇️ Scroll down to see the full summary -
General thermodynamic efficiency loss, aging and Gompertz mortality law
Abstract:⬇️ Scroll down to see the full summaryA simple and general thermodynamic theory is applied to describe the irreversible aspects of the continuous process of functional efficiency loss, which occurs in dissipative biological structures after they reach maturity [1]. This theory, among other things, follows Prigogine [2] by considering that these dissipative structures perform their functions and carry out cyclical processes per se since they are self-organizing away from equilibrium. By using the irreversible thermodynamic theory of aging by Montemayor-Aldrete et al [1], we have obtained results such as the following: The accumulated damage that occurs in dissipative biological structures after they reach maturity, which is the product of linear loss of functional efficiency with time, leads to the law of exponential mortality rate by Gompertz. The average solar power volumetric density of frequency ν dissipated by circular molecules of radius , which reside on the inner surface of some lipid vesicles that float in the Archean oceans and that contain water and other chemical components are obtained. Such expression resembles the Stefan–Boltzmann law which describes the power radiated from a black body in terms of its temperature. Also, an expression for the volumetric density of the average entropy production rate by molecules of radius is obtained. Finally, the coupling processes that occur between the matter and heat fluxes between the interior and the exterior of lentil-shaped lipid vesicles pumped by the solar radiation action are analyzed qualitatively as well as their possible consequences in relation to the prebiotic chemical evolution of dissipative systems that can give rise to life.
