BEGIN:VCALENDAR VERSION:2.0 PRODID:researchseminars.org CALSCALE:GREGORIAN X-WR-CALNAME:researchseminars.org BEGIN:VEVENT SUMMARY:Gregório Pacelli Bessa (Universidade Federal do Ceará) DTSTART:20200417T200000Z DTEND:20200417T210000Z DTSTAMP:20260422T225755Z UID:SGFM/1 DESCRIPTION:Title: Gre en function and Dirichlet spectrum.\nby Gregório Pacelli Bessa (Unive rsidade Federal do Ceará) as part of Seminario de Geometría y Física - Matemática UCN-USP\n\n\nAbstract\nIn this talk\, we show that the first e igenvalue $\\lambda_1(\\Omega)$ of the Laplacian of a bounded domain with smooth boundary can be obtained by S. Sato's iteration scheme of the Green operator.\nWe also prove an identity relating the radial eigenvalues of a geodesic ball centered at the origin $B_r$ for a model manifold $M_h^n$ of an isoperimetric quotient.\n\nThese results are joint work with Vicent Gimeno (Casteló\, Spain) and Luquesio Jorge (UFC\, Brazil).\n LOCATION:https://researchseminars.org/talk/SGFM/1/ END:VEVENT BEGIN:VEVENT SUMMARY:Chris Woodward (Rutgers University) DTSTART:20200430T200000Z DTEND:20200430T210000Z DTSTAMP:20260422T225755Z UID:SGFM/2 DESCRIPTION:Title: Fuk aya categories and blow-ups\nby Chris Woodward (Rutgers University) as part of Seminario de Geometría y Física - Matemática UCN-USP\n\n\nAbst ract\nI will talk about joint work with Sushmita Venugopalan and Guangbo X u describing the Fukaya category of the blow-up of a symplectic manifold a t a point.\n LOCATION:https://researchseminars.org/talk/SGFM/2/ END:VEVENT BEGIN:VEVENT SUMMARY:José Figueroa-O'Farrill (University of Edinburgh) DTSTART:20200514T200000Z DTEND:20200514T210000Z DTSTAMP:20260422T225755Z UID:SGFM/3 DESCRIPTION:Title: Sup ersymmetry and Lie algebra deformations\nby José Figueroa-O'Farrill ( University of Edinburgh) as part of Seminario de Geometría y Física - Ma temática UCN-USP\n\n\nAbstract\nI will summarise recent work in collabora tion with Andrew Beckett\, Paul de Medeiros\, and Andrea Santi concerning the generalised Spencer cohomology of Lie superalgebras and its applicatio n to the classification problem of supersymmetric supergravity backgrounds and to the construction of supersymmetric field theories in curved space. I will not assume any prior knowledge of supergravity or supersymmetric field theories.\n LOCATION:https://researchseminars.org/talk/SGFM/3/ END:VEVENT BEGIN:VEVENT SUMMARY:Marcos Jardim (Universidade Estadual de Campinas) DTSTART:20200528T200000Z DTEND:20200528T210000Z DTSTAMP:20260422T225755Z UID:SGFM/4 DESCRIPTION:Title: Com plex instantons\nby Marcos Jardim (Universidade Estadual de Campinas) as part of Seminario de Geometría y Física - Matemática UCN-USP\n\n\nAb stract\nI will ADHM-like description of non-singular\, anti-self-dual conn ections on the euclidean space with gauge group $\\mathrm{SL}(2\,\\mathbb{ C})$\, based on a complexified version of the ADHM equations. I will also discuss how these complex instantons relate to torsion free sheaves on the twistor space.\n LOCATION:https://researchseminars.org/talk/SGFM/4/ END:VEVENT BEGIN:VEVENT SUMMARY:M. Pilar García del Moral (Universidad de Antofagasta) DTSTART:20200611T200000Z DTEND:20200611T210000Z DTSTAMP:20260422T225755Z UID:SGFM/5 DESCRIPTION:Title: Flu xes\, Twisted Tori\, Monodromy and $U(1)$ supermembranes\nby M. Pilar García del Moral (Universidad de Antofagasta) as part of Seminario de Geo metría y Física - Matemática UCN-USP\n\n\nAbstract\nIn this talk I will discuss about recent advances in the characterization of Supermembrane Th eory with constant fluxes. I will show that the $D=11$ Supermembrane theor y (M2-brane) compactified on a $M_9\\times T^2$ target space\, with consta nt fluxes $C_\\pm$ naturally incorporates the geometrical structure of a t wisted torus. Its global formulation corresponds to a twisted torus bundle fibered over the world volume of the supermembrane. This structure allows to understand better its effective limit described by the Type II Gauged supergravities. The spectrum of the theory is purely discrete\, with fini te multiplicity. The theory is invariant under symplectomorphisms connecte d and non-connected to the identity\, a result relevant to guarantee the U -dual invariance of the theory. The Hamiltonian of the theory exhibits int eresting new $U(1)$ gauge and global symmetries on the world volume induce d by the symplectomorphism transformations. I will discuss also its super symmetric algebra. The zero modes decouple from the nonzero ones. The nonz ero mode algebra corresponds to a massive superalgebra that preserves eith er $1/2$ or $1/4$ of the original supersymmetry depending on the state con sidered.\n\nThis talk is based on:\n\n1.Fluxes\, Twisted tori\, Monodromy and $U(1)$ Supermembranes. arXiv: 2005.06397\n By MPGM\, Camilo Las Heras\ , Pablo León\, Joselen Peña and Alvaro Restuccia.\n\n2. M2-branes in a constant flux background. Physics Letters B\, 797\, 2019.\nBy MPGM\, Camil o Las Heras\, Pablo León\, Joselen Peña and Alvaro Restuccia.\n LOCATION:https://researchseminars.org/talk/SGFM/5/ END:VEVENT BEGIN:VEVENT SUMMARY:Nuno Cardoso (University of Miami) DTSTART:20200625T200000Z DTEND:20200625T210000Z DTSTAMP:20260422T225755Z UID:SGFM/6 DESCRIPTION:Title: Tow ards a new technique to compute the Orlov spectrum\nby Nuno Cardoso (U niversity of Miami) as part of Seminario de Geometría y Física - Matemá tica UCN-USP\n\n\nAbstract\nA generator of a triangulated category is an o bject from which we can obtain the whole category through certain operatio ns. Associated to a generator\, there is the notion of the generation time \, which is the number describing how long the rebuilding process takes. T he generation time of the fastest generator is called the Rouquier dimensi on of the category and it is conjectured that the Rouquier dimension of th e derived category of a smooth projective variety of dimension $n$ is exac tly $n$. Orlov suggested that in order to extract additional geometric inf ormation from the category\, one should study all possible generation time s – the Orlov spectrum. Later\, Ballard\, Favero\, and Katzarkov develop ed considerably our understanding of the topic\, making connections to rat ionality\, computing the Orlov spectrum in several cases and finding bound s for it. In this talk\, we will review part of their results and discuss our work in progress on a new technique to compute the Orlov spectrum\, wh ich takes inspiration on Abouzaid's criterion for generating the Fukaya ca tegory in terms of open-closed maps.\n LOCATION:https://researchseminars.org/talk/SGFM/6/ END:VEVENT BEGIN:VEVENT SUMMARY:Mark Gross (University of Cambridge) DTSTART:20200709T183000Z DTEND:20200709T200000Z DTSTAMP:20260422T225755Z UID:SGFM/7 DESCRIPTION:Title: Int rinsic Mirror Symmetry\nby Mark Gross (University of Cambridge) as par t of Seminario de Geometría y Física - Matemática UCN-USP\n\n\nAbstract \nI will talk about joint work with Bernd Siebert\, proposing a\ngeneral m irror construction for log Calabi-Yau pairs\, i.e.\, a pair $(X\,D)$\nwith $D$ a "maximally degenerate" boundary divisor and $K_X+D=0$\, and for\nma ximally unipotent degenerations of Calabi - Yau manifolds. We accomplish\n this by constructing the coordinate ring or homogeneous coordinate ring\nr espectively in the two cases\, using certain kinds of Gromov-Witten\ninvar iants we call "punctured invariants"\, developed jointly with\nAbramovich and Chen.\n LOCATION:https://researchseminars.org/talk/SGFM/7/ END:VEVENT BEGIN:VEVENT SUMMARY:Koushik Ray (Indian Association for the Cultivation of Science) DTSTART:20200723T183000Z DTEND:20200723T200000Z DTSTAMP:20260422T225755Z UID:SGFM/8 DESCRIPTION:Title: Con formal Correlation functions in four dimensions from Quaternionic Lauricel la system\nby Koushik Ray (Indian Association for the Cultivation of S cience) as part of Seminario de Geometría y Física - Matemática UCN-USP \n\n\nAbstract\nI shall discuss how the correlation functions in Euclidean conformal field theories in four dimensions are expressed as representati ons of the conformal group $SL(2\,\\mathbb H)$\, $\\mathbb H$ being the fi eld of quaternions\, on the configuration space of points. The representat ions are obtained in terms of Lauricella system\nfor quaternions\, general izing the two-dimensional counterpart where the correlation functions pert ain to the group $\\mathrm{SL}(2\,\\mathbb C)$.\n LOCATION:https://researchseminars.org/talk/SGFM/8/ END:VEVENT BEGIN:VEVENT SUMMARY:J. Sebastián Báez (Universidade Estadual de Campinas) DTSTART:20200910T190000Z DTEND:20200910T200000Z DTSTAMP:20260422T225755Z UID:SGFM/9 DESCRIPTION:Title: Coa djoint semi-direct orbit andsymplectic Deformations\nby J. Sebastián Báez (Universidade Estadual de Campinas) as part of Seminario de Geometr ía y Física - Matemática UCN-USP\n\n\nAbstract\nGiven a non-compact sem isimple Lie algebra $\\mathfrak{g}$\, we induce on it a semi-direct produc t structure such that its coadjoint orbit can be seen as a deformation by diffeomorphism of the classical semisimple adjoint orbit (in fact\, a sym plectomorphism with respect to the Hermitian symplectic form). As an appli cation of this deformation\, we can find out some Lagrangian submanifolds (with respect to the Hermitian form) of the adjoint orbit.\n\nThis talk wi ll be delivered in Spanish with slides in English.\n LOCATION:https://researchseminars.org/talk/SGFM/9/ END:VEVENT BEGIN:VEVENT SUMMARY:Francisco Rubilar (Universidad Católica del Norte) DTSTART:20200924T190000Z DTEND:20200924T200000Z DTSTAMP:20260422T225755Z UID:SGFM/10 DESCRIPTION:Title: Th e Kuranishi map for moduli of vector bundles on surfaces of general type.< /a>\nby Francisco Rubilar (Universidad Católica del Norte) as part of Sem inario de Geometría y Física - Matemática UCN-USP\n\n\nAbstract\nWe use the Kuranishi map to study moduli of rank two vector bundles on surfaces of general type\, focusing on the case of product of smooth projective cur ves. More concretely\, we compare the set of stable bundles to the irreduc ible component of the stack containing them and prove that they have the s ame homology at a range bounded by $c_2$.\n\nThis is joint work with E. Ba llico\, E. Gasparim\, and B. Suzuki.\n LOCATION:https://researchseminars.org/talk/SGFM/10/ END:VEVENT BEGIN:VEVENT SUMMARY:Henrique N. Sá Earp (Universidade Estadual de Campinas) DTSTART:20201008T190000Z DTEND:20201008T200000Z DTSTAMP:20260422T225755Z UID:SGFM/11 DESCRIPTION:Title: In stantons on Sasakian 7-manifolds\nby Henrique N. Sá Earp (Universidad e Estadual de Campinas) as part of Seminario de Geometría y Física - Mat emática UCN-USP\n\n\nAbstract\nWe study a natural contact instanton (CI) equation on gauge fields over $7$-dimensional Sasakian manifolds\, which i s closely related both to the transverse Hermitian Yang-Mills (tHYM) condi tion and the $G_2$-instanton equation. We obtain\, by Fredholm theory\, a finite-dimensional local model for the moduli space of irreducible solutio ns. We derive cohomological conditions for smoothness\, and we express its dimension in terms of the index of a transverse elliptic operator. Finall y we show that the moduli space of self dual contact instantons (ASDI) is Kähler\, in the Sasakian case. As an instance of concrete interest\, we s pecialise to transversely holomorphic Sasakian bundles over contact Calabi -Yau $7$-manifolds\, and we show that\, in this context\, the notions of c ontact instanton\, integrable $G_2$-instanton and HYM connection coincide. \n LOCATION:https://researchseminars.org/talk/SGFM/11/ END:VEVENT BEGIN:VEVENT SUMMARY:Sebastián Reyes-Carocca (Universidad de La Frontera) DTSTART:20201022T190000Z DTEND:20201022T200000Z DTSTAMP:20260422T225755Z UID:SGFM/12 DESCRIPTION:Title: On regular non-cyclic covers of the projective line\nby Sebastián Reyes -Carocca (Universidad de La Frontera) as part of Seminario de Geometría y Física - Matemática UCN-USP\n\n\nAbstract\nA regular cover of the proje ctive line is a compact Riemann surface $S$ (or smooth projective algebrai c curve) with action of a group $G$ in such a way that the corresponding q uotient $S/G$ has genus zero. In this talk we shall consider those cases i n which $G$ is non-cyclic and of order $pq$ where $p$ and $q$ are prime nu mbers. We shall discuss some recent results concerning the surfaces $S$ as before that form complex one-dimensional families in the moduli space of Riemann surfaces\, and some related aspects concerning their Jacobian vari eties.\n LOCATION:https://researchseminars.org/talk/SGFM/12/ END:VEVENT BEGIN:VEVENT SUMMARY:Stephen Griffeth (Universidad de Talca) DTSTART:20201126T190000Z DTEND:20201126T200000Z DTSTAMP:20260422T225755Z UID:SGFM/13 DESCRIPTION:Title: Re presentations of Weyl groups via the geometry of the Springer resolution\nby Stephen Griffeth (Universidad de Talca) as part of Seminario de Geo metría y Física - Matemática UCN-USP\n\n\nAbstract\nIn this expository talk\, I will explain how to relate representations of Weyl groups to perv erse sheaves. Harish-Chandra's philosophy of cusp forms appears in a way t hat might be surprising.\n LOCATION:https://researchseminars.org/talk/SGFM/13/ END:VEVENT BEGIN:VEVENT SUMMARY:Marija Dimitrijevic (University of Belgrade) DTSTART:20201105T190000Z DTEND:20201105T200000Z DTSTAMP:20260422T225755Z UID:SGFM/14 DESCRIPTION:Title: L- infinity Algebras of Gravity and their Braided Deformations\nby Marija Dimitrijevic (University of Belgrade) as part of Seminario de Geometría y Física - Matemática UCN-USP\n\n\nAbstract\nIn this talk we will descri be the cyclic $L_\\infty$-algebra formulation\nof classical general relati vity without matter fields in the\nEinstein-Cartan (EC) formalism. We will start with a brief review of\n$L_\\infty$-algebra and then apply this for malism to the EC gravity.\nAfter discussing the $L_\\infty$ structure of c lassical (undeformed)\ngravity\, we will present the $L_\\infty$ formulati on of noncommutative\n(deformed\, braided) gravity. The noncommutativity i s introduced via the\nDrinfeld twist and the corresponding symmetries (dif feomorphisms and\nlocal Lorentz symmetry) are given in terms of twisted (b raided)\nHopf-algebras. For simplicity\, we will discuss only the three an d four-dimensional cases. Nevertheless\, the whole construction can be don e in\nan arbitrary dimensional case.\n LOCATION:https://researchseminars.org/talk/SGFM/14/ END:VEVENT BEGIN:VEVENT SUMMARY:Yang-Hui He (City\, University of London & Merton\, University of Oxford) DTSTART:20201112T190000Z DTEND:20201112T200000Z DTSTAMP:20260422T225755Z UID:SGFM/15 DESCRIPTION:Title: Un iverses as Bigdata: Superstrings\, Calabi-Yau Manifolds and Machine-Learni ng\nby Yang-Hui He (City\, University of London & Merton\, University of Oxford) as part of Seminario de Geometría y Física - Matemática UCN- USP\n\n\nAbstract\nWe review how historically the problem of string phenom enology lead theoretical physics first to algebraic/differential geometry\ , and then to computational geometry\, and now to data science and AI.\n\n With the concrete playground of the Calabi-Yau landscape\, accumulated by the collaboration of physicists\, mathematicians\, and computer scientists over the last 4 decades\, we show how the latest techniques in machine-le arning can help explore problems of physical and mathematical interest\, f rom geometry to group theory\, to combinatorics and number theory.\n LOCATION:https://researchseminars.org/talk/SGFM/15/ END:VEVENT BEGIN:VEVENT SUMMARY:Edward Hirst (City\, University of London) DTSTART:20201203T190000Z DTEND:20201203T200000Z DTSTAMP:20260422T225755Z UID:SGFM/16 DESCRIPTION:Title: Ma chine-Learning Dessins d'Enfants: Explorations via Modular and Seiberg-Wit ten Curves\nby Edward Hirst (City\, University of London) as part of S eminario de Geometría y Física - Matemática UCN-USP\n\n\nAbstract\nWe i ntroduce in the context of Calabi-Yau manifolds\, and then apply machine-l earning to\, the study of dessins d'enfants. Specifically\, we investigate a class of dessins which reside at the intersection of the investigations of modular subgroups and extremal elliptic K3 surfaces. A deep feed-forwa rd neural network performs classification of Galois extension degree over the rationals\, known to be a difficult problem. The classifications reach ed accuracy 0.92 relatively quickly.\nIn relation to papers: 2004.05218 & 2001.01212\n LOCATION:https://researchseminars.org/talk/SGFM/16/ END:VEVENT BEGIN:VEVENT SUMMARY:Giuseppe De Nittis (Pontificia Universidad Católica de Chile) DTSTART:20201217T190000Z DTEND:20201217T200000Z DTSTAMP:20260422T225755Z UID:SGFM/17 DESCRIPTION:Title: Qu antization of edge currents along magnetic interfaces: A K-theory approach \nby Giuseppe De Nittis (Pontificia Universidad Católica de Chile) as part of Seminario de Geometría y Física - Matemática UCN-USP\n\n\nAbst ract\nThe purpose of this talk is to explain how to describe the propagati on of topological currents along magnetic interfaces (also known as magnet ic walls) of a two-dimensional material using K-theory. We initially consi der tight-binding magnetic models associated with generic magnetic multi-i nterfaces and we will describe the K-theoretical setting in which a bulk-i nterface duality can be derived. Then\, we will focus on the (nontrivial) case of the Iwatsuka magnetic field. The exposition is intended to be ped agogical and aimed at a non-specialist audience.\n\nWork in collaboration with: Esteban Gutiérrez\n LOCATION:https://researchseminars.org/talk/SGFM/17/ END:VEVENT BEGIN:VEVENT SUMMARY:Emilia Mezzetti (Università degli Studi di Trieste) DTSTART:20210408T200000Z DTEND:20210408T210000Z DTSTAMP:20260422T225755Z UID:SGFM/18 DESCRIPTION:Title: Le fschetz properties\, Laplace equations and Galois coverings\nby Emilia Mezzetti (Università degli Studi di Trieste) as part of Seminario de Geo metría y Física - Matemática UCN-USP\n\n\nAbstract\nIn an article in co llaboration with Rosa M. Mirò-Roig and Giorgio Ottaviani (Canad. J. Math. 65\, 2013)\, we established a relation\, due to apolarity\, between Artin ian homogeneous ideals of a polynomial ring not satisfying the Weak Lefsch etz Property - WLP - and projective varieties that verify a Laplace equati on of a certain order s\, i.e. such that all the s-osculating spaces have dimension less than expected. Thanks to this relation\, it is possible to extend to various classes of toric varieties some classical results due to Eugenio Togliatti. In the seminar\, I will introduce these notions and I will speak of some recent results in collaboration with Liena Colarte and Rosa M. Miro'-Roig\, relating them to cyclic Galois coverings.\n LOCATION:https://researchseminars.org/talk/SGFM/18/ END:VEVENT BEGIN:VEVENT SUMMARY:Brent Pym (McGill University) DTSTART:20210422T200000Z DTEND:20210422T210000Z DTSTAMP:20260422T225755Z UID:SGFM/19 DESCRIPTION:Title: A global Weinstein splitting theorem for holomorphic Poisson manifolds.\ nby Brent Pym (McGill University) as part of Seminario de Geometría y Fí sica - Matemática UCN-USP\n\n\nAbstract\nA foundational result in Poisson geometry\, due to Weinstein\,\nstates that any Poisson bracket on a manif old can be written locally as\nthe Poisson bracket of symplectic form in c anonical coordinates\, and a\nPoisson bracket that vanishes at a point.   A key consequence is that\nevery Poisson manifold has a canonical foliatio n with symplectic leaves.\nI will give an introduction to these ideas\, an d then discuss the problem\nof globalizing Weinstein's decomposition\, to split the manifold itself\n(or a covering thereof) as a product of a sympl ectic leaf and a\ntransverse Poisson manifold.  While the existence of su ch a splitting is\nrare in the context of smooth manifolds\, it turns out to be automatic\nfor holomorphic Poisson structures on compact Kähler man ifold admitting\na simply-connected compact symplectic leaf.  This talk i s based on joint\nwork with Stéphane Druel\, Jorge Vitório Pereira\, and Frédéric Touzet\,\nwhich in turn relies in an essential way on a notion of "subcalibrations"\nin Poisson geometry introduced recently by Pedro Fr ejlich and Ioan Mărcuț.\n LOCATION:https://researchseminars.org/talk/SGFM/19/ END:VEVENT BEGIN:VEVENT SUMMARY:João Nuno Mestre (University of Coimbra) DTSTART:20210506T200000Z DTEND:20210506T210000Z DTSTAMP:20260422T225755Z UID:SGFM/20 DESCRIPTION:Title: De formations of symplectic groupoids\nby João Nuno Mestre (University o f Coimbra) as part of Seminario de Geometría y Física - Matemática UCN- USP\n\n\nAbstract\nSymplectic groupoids are geometric objects that functio n as global counterparts to Poisson manifolds\, in the same way\, that Lie groups are global counterparts to Lie algebras. In this talk\, I will fir st give an idea of what these objects are and of how that analogy works\, and I will then present the construction of the deformation cohomology con trolling deformations of symplectic groupoids.\nI will then compute this c ohomology in some examples\, explain how to use it in a Moser path argumen t\, and relate it to the deformation theory of the corresponding Poisson m anifolds. The talk is based on joint work with Cristian Cárdenas (UFF) an d Ivan Struchiner (USP).\n LOCATION:https://researchseminars.org/talk/SGFM/20/ END:VEVENT BEGIN:VEVENT SUMMARY:Jorge Gamboa (Universidad de Santiago de Chile) DTSTART:20210520T200000Z DTEND:20210520T210000Z DTSTAMP:20260422T225755Z UID:SGFM/21 DESCRIPTION:Title: Co rrections of the magnetic moment of the muon and possibilities of new phys ics\nby Jorge Gamboa (Universidad de Santiago de Chile) as part of Sem inario de Geometría y Física - Matemática UCN-USP\n\n\nAbstract\nThe se minar will explain the meaning of the recent measurements by FermiLab and Brookhaven of the anomalous magnetic moment of the muon and the possibilit ies that these results have to understand Physics beyond the standard mode l.\n LOCATION:https://researchseminars.org/talk/SGFM/21/ END:VEVENT BEGIN:VEVENT SUMMARY:James Pascaleff (University of Illinois) DTSTART:20210603T200000Z DTEND:20210603T210000Z DTSTAMP:20260422T225755Z UID:SGFM/22 DESCRIPTION:Title: St ructures in the Floer theory of Symplectic Groupoids\nby James Pascale ff (University of Illinois) as part of Seminario de Geometría y Física - Matemática UCN-USP\n\n\nAbstract\nA symplectic groupoid is a Lie groupoi d with a multiplicative symplectic form. We take the perspective that such an object is a symplectic manifold with an extra categorical structure. A pplying the machinery of Floer theory\, the extra structure is expected to yield a monoidal structure on the Fukaya category. I will take an example s-based approach to work out what these structures are\, focusing on cases such as the cotangent bundle of a compact manifold.\n LOCATION:https://researchseminars.org/talk/SGFM/22/ END:VEVENT BEGIN:VEVENT SUMMARY:Silvina Ponce Dawson (Universidad de Buenos Aires) DTSTART:20210617T200000Z DTEND:20210617T210000Z DTSTAMP:20260422T225755Z UID:SGFM/23 DESCRIPTION:Title: Ne sted pooling for the efficient detection of infected samples\nby Silvi na Ponce Dawson (Universidad de Buenos Aires) as part of Seminario de Geom etría y Física - Matemática UCN-USP\n\n\nAbstract\nThe rapid spread of the SARS-CoV-2 pandemic confronted us with the need of designing large-sca le\, cost-effective testing programs. To this end\, running the test on po oled samples can be a solution if the detection method (in the case of SAR S-CoV-2\, the method to detect the viral RNA) is sensitive enough. Cost-ef fective strategies\, on the other hand\, require the definition of efficie nt deconvolution and re-testing procedures for the identifcation of the ca rrier. In this talk I will describe an efficient nested pooling strategy t hat we have devised in collaboration with Ines Armendariz\, Pablo Ferrari\ , Daniel Fraiman and Mario Martinez and discuss its practical implementati on using droplet digital PCR (ddPCR)\, which was shown to be 10-100 times more sensitive than the current gold standard for viral RNA detection\, RT -qPCR. The latter part of the work was also done with Hugo Menzella. Among other aspects\, I will discuss how the RNA quantification that ddPCR prov ides at the end of the test and the nested nature of the strategy can be c ombined to perform self-consistency tests for a better identification of i nfected individuals and of unviable samples. A user-friendly interface is available at pooling.df.uba.ar for those who want to define their best poo ling strategy under different constraints.\n LOCATION:https://researchseminars.org/talk/SGFM/23/ END:VEVENT BEGIN:VEVENT SUMMARY:Mark Colarusso (University of South Alabama) DTSTART:20210701T200000Z DTEND:20210701T210000Z DTSTAMP:20260422T225755Z UID:SGFM/24 DESCRIPTION:Title: Ge ometry of complex Gelfand - Zeitlin integrable systems\nby Mark Colaru sso (University of South Alabama) as part of Seminario de Geometría y Fí sica - Matemática UCN-USP\n\n\nAbstract\nWe discuss the geometry of the G elfand-Zeitlin integrable systems on the complex general linear and orthog onal Lie algebras. We show how geometric invariant theory and the theory o f spherical varieties can be used to understand the fibres of the moment m aps of these systems and discuss possible applications to the study of Gel fand - Zeitlin modules.\n LOCATION:https://researchseminars.org/talk/SGFM/24/ END:VEVENT BEGIN:VEVENT SUMMARY:Soren Galatius (University of Copenhagen) DTSTART:20210715T200000Z DTEND:20210715T210000Z DTSTAMP:20260422T225755Z UID:SGFM/25 DESCRIPTION:Title: Eq uivariant cobordism categories\nby Soren Galatius (University of Copen hagen) as part of Seminario de Geometría y Física - Matemática UCN-USP\ n\n\nAbstract\nI will explain recent work with G. Szucs (arXiv:1805.12342) studying a category $\\mathrm{Cob}_d^G$ whose objects are closed $(d-1)$- manifolds equipped with an action of a finite group $G$\, and whose morphi sms are equivariant cobordisms. The main result determines the homotopy ty pe of the classifying space of this category in terms of equivariant stabl e homotopy theory. Time permitting\, I will outline why this may be a step towards an equivariant Madsen-Weiss theorem.\n LOCATION:https://researchseminars.org/talk/SGFM/25/ END:VEVENT END:VCALENDAR