• Salón K201 (antes Salón de Usos Múltiples del Nivel H), CIMAT Guanajuato

• 13:00-14:00. Laplacianos Combinatorios: aspectos espectrales y probabilístico-algebraicos
  Carlos Vargas Obieta, CONACYT-CIMA

• Sesión doble
• Salón K201 (antes Salón de Usos Múltiples del Nivel H), CIMAT Guanajuato

12:00 - 13:00. Persistence of geodesic spaces
Ziga Virk, University of Ljubljuana, Slovenia
Resumen: Given a locally contractible geodesic space, say a Riemannian manifold, we show how a critical value of the one-dimensional persistence corresponds to a closed geodesic. Using this result we can explain the surprising relationship between the Vietoris Rips and Cech induced persistences. It also allows us to deduce several results about approximations by discrete samples, including an improved stability theorem. We the show how to utilize contractions and deformation contractions to extract geometric information from higher-dimensional persistence. For example, we can detect certain contractible geodesic loops by higher-dimensional persistence.

13:00 - 14:00. Cálculo de fenotipos cuantitativos en redes genético-metabólicas mediante variedades tóricas
Marco Polo Castillo Villalba, Centro de Ciencias Genómicas, UNAM
www.ccg.unam.mx/genomica-computacional
Resumen: En las últimas décadas, el desarrollo de las tecnologías en secuenciamiento del genoma y la obtención de datos genómicos de manera masiva (High-throughput y Chip-Seq) de diversos organismos, han permitido una nueva manera de abstraer y modelar la expresión en genes y la interacción con sus productos (relación genotipo-fenotipo), esta manera es a través del concepto de redes genético-metabólicas, las cuales son familias de grafos bidireccionales que capturan información de la dinámica de los genes y sus fenotipos expresados, así como de las demás moléculas participantes en la red. En este trabajo, veremos como este tipo de familias de redes puede ser modelado a través de variedades tóricas y como los invariantes algebraicos asociados a la red (ideales tóricos), reproducen fenotipos cuantitativos de redes genéticas reportadas en el trabajo de M. Savageau en Biología de Sistemas, así como el cálculo de nuevos fenotipos moleculares.

• Salón K201 (antes Salón de Usos Múltiples del Nivel H), CIMAT Guanajuato

13:00 - 14:00. El algoritmo Mapper y algunas aplicaciones a Astronomía
Víctor Andrés Amaya, Departamento de Matemáticas, Universidad de Guanajuato

• CIMAT Guanajuato, Auditorio J.A. Canavati

12:00 hrs. Topological, Geometric and Combinatorial Properties of Random Polyominoes
Érika Berenice Roldán Roa
Examen para la Obtención del grado de Doctora en Ciencias con Orientación en Probabilidad y Estadística

Resumen: We study two models of random shapes in this thesis: the Eden Cell Growth Model (EGM) and uniform and percolation distributed polyominoes (also known as lattice-based animals). These models have long been of interest in mathematical physics, probability, and statistical mechanics. Both structures have interesting topological, combinatorial, and geometrical properties. However, until now, tools from stochastic topology and topological data analysis have not been used to study these properties. By introducing these methods and techniques, we established and proved new results that increase the understanding of topological, geometric, and combinatoric properties of these random models.

First, we study the maximum number of holes (the rank of the first homology group) that a polyomino with a given number of tiles can have. We prove a tight bound for the asymptotic behavior and give an exact formula for an infinite sequence of natural numbers for this maximum number of holes. Our second set of contributions of this thesis are about the rate of growth of the expectation of the number of holes in a polyomino with uniform and percolation distributions. We prove the existence of linear bounds for the expected number of holes of a polyomino with respect to both the uniform and percolation distributions. Furthermore, we exhibit particular constants for the upper and lower bounds in the uniform distribution case. Finally, we characterize how the rank of the first homology group, of the stochastic process defined by the EGM, changes in time. This allowed us to design and implement a new algorithm that computes the persistence homology associated to this stochastic process at each time and that keeps track of geometric features of the homology of the process as the area and location of the holes. We present and analyze the results of the computational experiments obtained with this algorithm. We also state conjectures based on these experiments about the asymptotic behavior of the number of holes, the locations of these holes, their associated area, and other geometric and topological properties of this stochastic process.