BEGIN:VCALENDAR VERSION:2.0 PRODID:researchseminars.org CALSCALE:GREGORIAN X-WR-CALNAME:researchseminars.org BEGIN:VEVENT SUMMARY:Erik Jansson DTSTART:20241211T150000Z DTEND:20241211T160000Z DTSTAMP:20260422T225820Z UID:gbgphd/1 DESCRIPTION:Title: A n actual real-life application of geodesic equations on Lie groups: protei ns\nby Erik Jansson as part of Gothenburg PhD seminar\n\nLecture held in MVL15.\n\nAbstract\nWhat is in the intersection of optimization\, geome tric mechanics and protein imaging? The contents of this talk! I have stud ied how to solve the problem of reconstructing protein conformations from very noisy electron microscopy images\, using techniques from geometric sh ape matching. By deforming an initial template using the action of a suita ble Lie group in an optimal way\, we can reconstruct the indirectly observ ed target conformation of the protein. In this talk\, I hope to introduce you to the beautiful concept of shape matching in a way that is FUN (Frien dly Understanding for Novices). References will be provided for those look ing to learn more.\n LOCATION:https://researchseminars.org/talk/gbgphd/1/ END:VEVENT BEGIN:VEVENT SUMMARY:Mattias Byléhn DTSTART:20241216T143000Z DTEND:20241216T153000Z DTSTAMP:20260422T225820Z UID:gbgphd/2 DESCRIPTION:Title: O ne or two perspectives on the Heisenberg group\nby Mattias Byléhn as part of Gothenburg PhD seminar\n\nLecture held in MVL14.\n\nAbstract\nMy a im with this talk is to illustrate the versatility of the Schrödinger rep resentation of the Heisenberg group. I will try to motivate its existence from a simple inverse problem for radars\, and if there is time then I wil l also explain some connections to theta functions in analytic number theo ry. No prior knowledge of any of these things will be assumed.\n LOCATION:https://researchseminars.org/talk/gbgphd/2/ END:VEVENT BEGIN:VEVENT SUMMARY:Ruben Seyer (Chalmers/GU) DTSTART:20250123T153000Z DTEND:20250123T160000Z DTSTAMP:20260422T225820Z UID:gbgphd/3 DESCRIPTION:Title: N on-reversible Markov samplers and parallel universes\nby Ruben Seyer ( Chalmers/GU) as part of Gothenburg PhD seminar\n\nLecture held in MVL14.\n \nAbstract\nWherein I try to make you see the light of Bayesian statistics \, its practical applications\, and we look at a few vignettes of my past and current projects.\n LOCATION:https://researchseminars.org/talk/gbgphd/3/ END:VEVENT BEGIN:VEVENT SUMMARY:Styrbjörn Käll DTSTART:20250131T150000Z DTEND:20250131T153000Z DTSTAMP:20260422T225820Z UID:gbgphd/4 DESCRIPTION:Title: C hemical hazards from the tip of the iceberg\nby Styrbjörn Käll as pa rt of Gothenburg PhD seminar\n\nLecture held in MVL14.\n\nAbstract\nEnviro nmental hazard assessments are reliant on toxicity data that cover multipl e organism groups. Generating experimental toxicity data is\, however\, re source-intensive and time-consuming. Computational methods are fast and co st-efficient alternatives\, but the low accuracy and narrow applicability domains have made their adaptation slow. In this presentation\, we will le arn the basics of chemical hazard assessment\, talk briefly about cheminfo rmatics\, and finally build intuition for why transformers are suitable mo dels for capturing the complex chemical and biological interactions necess ary for accurate toxicity prediction. Finally\, we will look at some resul ts from our recent publication\, demonstrating how transformers capture to xicity-specific features directly from the chemical structures themselves. \n LOCATION:https://researchseminars.org/talk/gbgphd/4/ END:VEVENT BEGIN:VEVENT SUMMARY:Rickard Cullman DTSTART:20250213T153000Z DTEND:20250213T160000Z DTSTAMP:20260422T225820Z UID:gbgphd/5 DESCRIPTION:Title: A taste of Ergodic Ramsey theory\nby Rickard Cullman as part of Gothenb urg PhD seminar\n\nLecture held in MVL14.\n\nAbstract\nErgodic Ramsey theo ry is a branch of mathematics that\, loosely speaking\, applies Ergodic th eory (measurable dynamics) to the study of certain number-theoretic proble ms. \n\nIn this talk I will give a quick introduction to both Ramsey theor y and Ergodic theory\, and how the two relate via the Furstenberg correspo ndence principle. I will conclude with a brief discussion of Szemeredi's t heorem on arithmetic progressions (often considered a highlight of 20:th c entury mathematics) and Furstenberg's ergodic-theoretic proof of it. I aim to convey how seemingly very abstract mathematical methods from measure t heory and functional analysis can be used to prove easily formulated numbe r-theoretic statements.\n LOCATION:https://researchseminars.org/talk/gbgphd/5/ END:VEVENT BEGIN:VEVENT SUMMARY:Anna Theorin Johansson DTSTART:20250220T153000Z DTEND:20250220T160000Z DTSTAMP:20260422T225820Z UID:gbgphd/6 DESCRIPTION:Title: Z aremba's conjecture and the circle method\nby Anna Theorin Johansson a s part of Gothenburg PhD seminar\n\nLecture held in MVL14.\n\nAbstract\nZa remba's conjecture from 1971 states that every natural number is the denom inator of a reduced fraction for which the partial quotients in its contin ued fraction expansion are bounded by an absolute constant. I will try to describe the motivation behind the problem and present some partial progre ss towards the conjecture.\n LOCATION:https://researchseminars.org/talk/gbgphd/6/ END:VEVENT BEGIN:VEVENT SUMMARY:Elias Nyholm DTSTART:20250227T153000Z DTEND:20250227T160000Z DTSTAMP:20260422T225820Z UID:gbgphd/7 DESCRIPTION:Title: G eometric deep learning\; or\, processing pictures of cute dogs using diffe rential geometry\nby Elias Nyholm as part of Gothenburg PhD seminar\n\ nLecture held in MVL14.\nAbstract: TBA\n LOCATION:https://researchseminars.org/talk/gbgphd/7/ END:VEVENT BEGIN:VEVENT SUMMARY:Robin van Haastrecht (GU/Chalmers) DTSTART:20250304T153000Z DTEND:20250304T160000Z DTSTAMP:20260422T225820Z UID:gbgphd/8 DESCRIPTION:Title: T he Wehrl inequality: the creation of a pure math conjecture\nby Robin van Haastrecht (GU/Chalmers) as part of Gothenburg PhD seminar\n\nLecture held in MVL14.\n\nAbstract\nIn the 1970s\, Wehrl first studied what would come to be called Wehrl type inequalities in the context of entropy in qua ntum mechanics. He conjectured a condition for when this entropy is minimi zed\, and this conjecture was proved shortly thereafter by Lieb\, who exte nded it to a more general context. This gave rise to an interesting area o f mathematical research. I will give a historical background and an overvi ew of the main problem\n LOCATION:https://researchseminars.org/talk/gbgphd/8/ END:VEVENT BEGIN:VEVENT SUMMARY:Julia Jansson DTSTART:20250403T143000Z DTEND:20250403T150000Z DTSTAMP:20260422T225820Z UID:gbgphd/9 DESCRIPTION:Title: M y research visit to UCLA\nby Julia Jansson as part of Gothenburg PhD s eminar\n\nLecture held in MVL14.\n\nAbstract\nI will present my experience during my research visit at UCLA including more informal aspects like pro s and cons\, PhD life in the US and life in LA. Then\, without going into too much mathematical details\, I will explain my research project\, which is about modeling earthquakes with spatio-temporal point processes\, and put it into the wider context of natural disasters in California. Lastly I will also mention how to finance a research stay using travel grants.\n LOCATION:https://researchseminars.org/talk/gbgphd/9/ END:VEVENT BEGIN:VEVENT SUMMARY:Jakob Jonsson DTSTART:20250410T143000Z DTEND:20250410T150000Z DTSTAMP:20260422T225820Z UID:gbgphd/10 DESCRIPTION:Title: The Whitney Method of Fundamental Solutions\nby Jakob Jonsson as part of Gothenburg PhD seminar\n\nLecture held in MVL14.\nAbstract: TBA\n LOCATION:https://researchseminars.org/talk/gbgphd/10/ END:VEVENT BEGIN:VEVENT SUMMARY:Philipp Misof DTSTART:20250416T143000Z DTEND:20250416T150000Z DTSTAMP:20260422T225820Z UID:gbgphd/11 DESCRIPTION:Title: The rotation-symmetric spherical cow of Deep Learning $\\rightarrow$ Wide Learning\nby Philipp Misof as part of Gothenburg PhD seminar\n\nLectur e held in MVL14.\n\nAbstract\nDue to the current boom in AI\, deep learnin g has become mainstream. The name is inspired by the fact that the corresp onding machine learning models are usually a composition of many layers of parametrized transformations. To swim against (or arguably orthogonal to) the tide\, what happens if we instead consider particularly 𝘸𝘪𝘥 𝘦 layers? In this talk\, I will present the spherical cow equivalent of neural networks and how this spherical cow can even be endowed with addit ional symmetry\, like 3d rotations (... the analogy may be lacking).\n LOCATION:https://researchseminars.org/talk/gbgphd/11/ END:VEVENT BEGIN:VEVENT SUMMARY:Björn Müller DTSTART:20250508T143000Z DTEND:20250508T150000Z DTSTAMP:20260422T225820Z UID:gbgphd/12 DESCRIPTION:Title: A visual walk through modelling stochastically evolving surfaces by SPDEs< /a>\nby Björn Müller as part of Gothenburg PhD seminar\n\nLecture held i n MVL14.\n\nAbstract\nThe seal (TM) will guide you on a journey from stoch astic processes on the unit sphere\, via solving SPDEs using spectral meth ods\, all the way to a variety of shape-shifting stochastic surfaces.\nTog ether\, we will explore how such surfaces arise from their building blocks and what we can learn about their shapes and shape-shifting ("Hölder reg ularity").\nLet yourself be fascinated by the wide range of applications o f these shape-shifters.\n\nSo sit back\, relax and enjoy an afternoon of a mazing imagery and seizure-inducing videos!\n LOCATION:https://researchseminars.org/talk/gbgphd/12/ END:VEVENT BEGIN:VEVENT SUMMARY:Jan Gundelach (University of Gothenburg) DTSTART:20250327T153000Z DTEND:20250327T160000Z DTSTAMP:20260422T225820Z UID:gbgphd/13 DESCRIPTION:Title: What are groupoids?\nby Jan Gundelach (University of Gothenburg) as pa rt of Gothenburg PhD seminar\n\nLecture held in MVL14.\n\nAbstract\nLet's follow the jumping dolphins and dive into the ocean of unit spaces togethe r just to exhibit a total lack of applications! Don't miss pimped algebrai c concepts disguised as a zoo of cute animals\, a lot of wild arrows\, spo radic French vocabulary\, and mysterious convoluted algebras!\n LOCATION:https://researchseminars.org/talk/gbgphd/13/ END:VEVENT BEGIN:VEVENT SUMMARY:Adélie Erard (Paris Cité University) DTSTART:20250527T143000Z DTEND:20250527T150000Z DTSTAMP:20260422T225820Z UID:gbgphd/14 DESCRIPTION:Title: Modeling fine-scale abundance dynamics: a dual frequentist and Bayesian ap proach applied to common birds\nby Adélie Erard (Paris Cité Universi ty) as part of Gothenburg PhD seminar\n\nLecture held in MVL14.\n\nAbstrac t\nUnderstanding how animal populations grow and change at a local scale i s key to studying ecosystems and supporting conservation efforts. In this study\, we explore two complementary methods to analyze data from the Fren ch Common Birds Monitoring Program (STOC).\n\nThe first method uses a stat istical model that views population changes as driven by births and deaths \, influenced by how individuals interact with each other and by environme ntal factors like climate and landscape. One major challenge is that these interactions often depend on spatial location and that the data are partl y random. To address this\, we develop new ways to estimate birth and deat h patterns and use a mathematical theory (called stabilization) that assum es interactions mostly happen at a local scale. This helps ensure that our estimates are accurate and reliable when predicting changes in bird numbe rs at specific locations.\n\nThe second method uses a Bayesian spatio-temp oral model\, estimated with a technique called INLA (Integrated Nested Lap lace Approximation). This model takes into account both space and time\, h elping us measure how environmental variables affect bird populations over time. It includes spatial patterns modeled through differential equations \, time trends using autoregressive effects\, and different responses depe nding on habitat type.\n LOCATION:https://researchseminars.org/talk/gbgphd/14/ END:VEVENT BEGIN:VEVENT SUMMARY:Lotta Eriksson DTSTART:20250424T143000Z DTEND:20250424T150000Z DTSTAMP:20260422T225820Z UID:gbgphd/15 DESCRIPTION:Title: Tracking of cancer using blood samples\nby Lotta Eriksson as part of G othenburg PhD seminar\n\nLecture held in MVL14.\nAbstract: TBA\n LOCATION:https://researchseminars.org/talk/gbgphd/15/ END:VEVENT BEGIN:VEVENT SUMMARY:Gustav Mårdby (Chalmers University of Technology) DTSTART:20250515T143000Z DTEND:20250515T150000Z DTSTAMP:20260422T225820Z UID:gbgphd/16 DESCRIPTION:Title: Can one hear the shape of a drum? A glimpse into spectral geometry and fla t tori\nby Gustav Mårdby (Chalmers University of Technology) as part of Gothenburg PhD seminar\n\nLecture held in MVL15.\n\nAbstract\nWhat can the sound of a drum tell us about its shape? This simple-sounding question \, famously posed by Mark Kac in 1966\, lies at the heart of spectral geom etry - a field that explores how the eigenvalues of the Laplacian relate t o the geometry of a space. In this talk\, we'll look at what information c an and cannot be recovered from the spectrum\, guided by classical results \, clever counterexamples\, and a few open problems. We'll then focus on t he case of flat tori\, where many of these results become particularly ele gant (and sometimes surprisingly tricky). In the end\, I will present a ne w result: a 6-dimensional triplet of isospectral\, non-isometric flat tori . No prior knowledge is expected - just bring your curiosity!\n LOCATION:https://researchseminars.org/talk/gbgphd/16/ END:VEVENT BEGIN:VEVENT SUMMARY:Mathis Rost (PhD student) DTSTART:20250522T143000Z DTEND:20250522T150000Z DTSTAMP:20260422T225820Z UID:gbgphd/17 DESCRIPTION:Title: A Brief Introduction to Spatial Point Processes\nby Mathis Rost (PhD s tudent) as part of Gothenburg PhD seminar\n\nLecture held in MVL14.\n\nAbs tract\nIn this talk\, I’ll give a brief and\, of course\, mostly visuall y pleasing introduction to my research area: spatial statistics. We’ll b egin with some general characteristics and a few real-world examples where point process models naturally arise. I’ll then introduce some key conc epts\, like intensity-based models and conditional intensity-based models\ , which form the backbone of spatial statistics. Toward the end\, I’ll t ouch on one of the topics from my first research paper (don’t worry\, I ’ll keep the math simple!).\n LOCATION:https://researchseminars.org/talk/gbgphd/17/ END:VEVENT BEGIN:VEVENT SUMMARY:Ruben Seyer (Chalmers University of Technology & University of Got henburg) DTSTART:20250904T143000Z DTEND:20250904T150000Z DTSTAMP:20260422T225820Z UID:gbgphd/18 DESCRIPTION:Title: How to take over your† local government using mathematics\nby Ruben Seyer (Chalmers University of Technology & University of Gothenburg) as pa rt of Gothenburg PhD seminar\n\nLecture held in MVL14.\n\nAbstract\n† If you are elected in Sweden and under some assumptions\n\nIt is a well-know n problem that mathematics is easy but politics is difficult.\nElectoral m athematics is concerned with constructing algorithms that convert vote cou nts to seat counts. Unfortunately\, nobody can agree on what makes such an algorithm "fair".\nWe review some famous theorems that show why.\nWe also review divisor methods\, in use in most proportional elections. These sat isfy certain satisfying theorems which may be indicative of their "fairnes s".\nFinally\, we consider some takeover attacks in local councils possibl e due to mathematical deficiencies in the Swedish electoral system highlig hted by Janson & Linusson (2022).\n LOCATION:https://researchseminars.org/talk/gbgphd/18/ END:VEVENT BEGIN:VEVENT SUMMARY:Erik Jansson DTSTART:20250918T143000Z DTEND:20250918T150000Z DTSTAMP:20260422T225820Z UID:gbgphd/19 DESCRIPTION:Title: How to compute the polar factorization of a matrix in a way you shouldn't< /a>\nby Erik Jansson as part of Gothenburg PhD seminar\n\nLecture held in MVL14.\n\nAbstract\nThe polar factorization is a way to decompose a square matrix into the product of an orthogonal factor and a positive-definite s ymmetric factor. There exist various ways to do this fast and efficiently\ , but in this talk\, I would like to present a method that is neither fast nor efficient. In fact\, it is completely inadvisable and should not be u sed for any application relying in any way on computing the polar factoriz ation. It is\, however\, interesting for an entirely different reason\, in that it arises in an unexpected and fascinating way. \nAfter having showc ased the method\, I will briefly explain its derivation by discussing the Gaussian optimal transport problem\, principal fiber bundles\, and gradien t flows to showcase that even numerical linear algebra can have deep geome tric roots.\n LOCATION:https://researchseminars.org/talk/gbgphd/19/ END:VEVENT BEGIN:VEVENT SUMMARY:Anna Theorin Johansson DTSTART:20250925T143000Z DTEND:20250925T150000Z DTSTAMP:20260422T225820Z UID:gbgphd/21 DESCRIPTION:Title: Draw me if you can: Constructions with Euclidean tools\nby Anna Theori n Johansson as part of Gothenburg PhD seminar\n\nLecture held in MVL14.\n\ nAbstract\nHow much geometry can you squeeze out of a straightedge and com pass? Trisect an angle? Maybe not. Draw a regular 17-gon? Absolutely. The ancient Greeks figured out how to draw sums\, differences\, products\, rat ios and square roots of given lengths\, as well as how to construct some g eometric figures from others\, but it took two millennia to finally comple tely close the case of constructible polygons. In this filler episode\, we ’ll cover the main ideas: which shapes can be drawn\, which can’t\, an d why.\n LOCATION:https://researchseminars.org/talk/gbgphd/21/ END:VEVENT BEGIN:VEVENT SUMMARY:Adrien Malacan DTSTART:20251120T150000Z DTEND:20251120T153000Z DTSTAMP:20260422T225820Z UID:gbgphd/23 DESCRIPTION:Title: The Curie point and the Ising model : when spins rebel.\nby Adrien Mal acan as part of Gothenburg PhD seminar\n\nLecture held in MVL14.\n\nAbstra ct\nLet's do a home experiment.\n\nTake two magnetized pieces of iron stuc k together (everyone has a pair lying around at home). Now\, simply heat t hem to about 770°C\, or 1043 K\, for the SI purists. Surprise: the two pi eces of iron no longer stick together! You may now clean your setup (if it hasn't burned) and return to your math research.\n\nIn this talk\, we wil l see why probability theory saw this coming - and why this exact temperat ure is less random than you might think.\n LOCATION:https://researchseminars.org/talk/gbgphd/23/ END:VEVENT BEGIN:VEVENT SUMMARY:Albert Vesterlund DTSTART:20251009T143000Z DTEND:20251009T150000Z DTSTAMP:20260422T225820Z UID:gbgphd/24 DESCRIPTION:Title: Packing my $\\mathcal{NP}$-complete suitcase(s)\nby Albert Vesterlund as part of Gothenburg PhD seminar\n\nLecture held in MVL14.\n\nAbstract\nH ave you ever wondered why packing your infinite amount of suitcases optima lly can be such a time-consuming task? Or perhaps you have simply enjoyed a game of Tetris at one point in your life? In any case\, you have most li kely poked your head into the world of packing problems before. And while these problems are intuitively quite simple\, the underlying truth is that they all hide some disturbing secret. \nJoin me in this talk where we wil l see what a packing problem actually is\, and why they are such a mess in practice.\n LOCATION:https://researchseminars.org/talk/gbgphd/24/ END:VEVENT BEGIN:VEVENT SUMMARY:Robin van Haastrecht DTSTART:20251024T133000Z DTEND:20251024T140000Z DTSTAMP:20260422T225820Z UID:gbgphd/25 DESCRIPTION:Title: How to eat a pizza\nby Robin van Haastrecht as part of Gothenburg PhD seminar\n\nLecture held in MVL14.\n\nAbstract\nA talk on Gauss's theorema egregium\, curvature and hopefully some hyperbolic geometry.\n LOCATION:https://researchseminars.org/talk/gbgphd/25/ END:VEVENT BEGIN:VEVENT SUMMARY:Mathis Rost (PhD student) DTSTART:20251204T153000Z DTEND:20251204T160000Z DTSTAMP:20260422T225820Z UID:gbgphd/26 DESCRIPTION:Title: A Month in Paris and some Spatial Mixing\nby Mathis Rost (PhD student) as part of Gothenburg PhD seminar\n\nLecture held in MVL14.\n\nAbstract\n In November I spent a research visit in Paris at MAP5 and Inria\, where be tween cafés\, croissants\, and getting lost in charming side streets\, I actually managed to do some mathematics. In this talk I’ll give a short overview of a new project that began during that visit. The topic is spati al mixing in Gibbs point processes and spatial birth–death processes.\n\ nWe’ll first discuss what spatial mixing and ergodicity mean in the cont ext of point processes. Then we’ll see why establishing mixing for Gibbs processes is notoriously difficult\, and how this motivates looking inste ad at spatial birth–death processes\, where such properties can be shown much more easily.\n LOCATION:https://researchseminars.org/talk/gbgphd/26/ END:VEVENT BEGIN:VEVENT SUMMARY:Lotta Eriksson DTSTART:20251106T153000Z DTEND:20251106T160000Z DTSTAMP:20260422T225820Z UID:gbgphd/27 DESCRIPTION:Title: The Galton-Watson process and aging cells\nby Lotta Eriksson as part o f Gothenburg PhD seminar\n\nLecture held in MVL14.\n\nAbstract\nThe Galton –Watson process was developed to explore the possible extinction of fami ly names\, sparked by a Victorian worry that aristocratic surnames were sl owly dying out. The Galton–Watson process models how populations evolve across generations\, where each individual produces a random number of off spring. In a multitype Galton-Watson process we allow the individuals to b e of different type to allow for different probabilistic behavior. In this talk\, I present a multitype Galton-Watson process to model populations o f cells that ages biologically by accumulating damage within the cell body . The cells have the ability to pass on part of its damage to its daughter cell\, resulting in rejuvenation and longer life spans. Furthermore\, I p resent how we can model a single cell using Markov chains.\n LOCATION:https://researchseminars.org/talk/gbgphd/27/ END:VEVENT BEGIN:VEVENT SUMMARY:Joseph Löfving DTSTART:20251208T153000Z DTEND:20251208T160000Z DTSTAMP:20260422T225820Z UID:gbgphd/28 DESCRIPTION:Title: Ruben on Rails: How to Steal a World Record from Middle Schoolers\nby Joseph Löfving as part of Gothenburg PhD seminar\n\nLecture held in MVL14 .\n\nAbstract\nThe Guinness Book of World Records lists the record for fas test journey between every station on the London Underground as 17 hours\, 46 minutes and 48 seconds. Gothenburg\, being colloquially known as "Litt le London"\, of course deserves a little record of its own\, substituting the underground for the tram network. This record is—to the speaker's kn owledge—currently held by two boys in their younger teens\, who claim a time of 5 hours and 19 minutes. In this talk\, we use mathematical optimiz ation techniques and a high-performance computing cluster to crush the dre ams of these two boys and claim the record for ourselves.\n\nJoin me as I develop Ruben on Rails¹\, an algorithm that finds the fastest journey pas sing all tram stops in a given day. During the talk\, we will see advanced optimization techniques such as establishing dominance\, solving the wron g problem\, and ignoring nearly all of Hisingen—all employed in the ende avor to spend several consecutive hours on public transport "efficiently". \n\n\n\n¹Since the topic (trams) is quintessentially Gothenburgian\, it i s only fitting that the algorithm has a name in the form of a Gothenburgia n pun. Now\, one shouldn't explain their jokes\, but I am too proud of thi s one\, and it is somewhat niche\, so I'll break that rule: there is a web application framework called Ruby on Rails\, and this work was done with —and initiated by—our very own Ruben Seyer\, hence Ruben on Rails. Not that web application frameworks are at all relevant here. Anyway\, I thin k this is hilarious\, and will gladly accept compliments for my comedic ge nius in written or oral form.\n LOCATION:https://researchseminars.org/talk/gbgphd/28/ END:VEVENT BEGIN:VEVENT SUMMARY:Michael Roop DTSTART:20251218T153000Z DTEND:20251218T160000Z DTSTAMP:20260422T225820Z UID:gbgphd/29 DESCRIPTION:Title: What are solutions to O(P)DEs?\nby Michael Roop as part of Gothenburg PhD seminar\n\nLecture held in MVL14.\n\nAbstract\nIn this talk\, I will ( try to) give a (soft) introduction to the geometric theory of differential equations. This theory makes rigorous sense of multivalued solutions to b oth ordinary and partial differential equations\, which serve as an altern ative to weak solutions developed in the functional analytic framework.\nT his is the only theory (I am aware of) that formulates precise sufficient conditions for integrability of general type ODEs (sort of “Galois theor y” for ODEs) in terms properties of their symmetry group. This result is known as the Lie-Bianchi theorem. Its particular case is the celebrated L iouville-Arnold theorem on integrability of Hamiltonian systems. If time p ermits (likely\, not)\, we will also see applications of this theory in di fferent areas: hydrodynamics\, Monge-Ampère equations\, classification pr oblems in algebra.\n LOCATION:https://researchseminars.org/talk/gbgphd/29/ END:VEVENT BEGIN:VEVENT SUMMARY:Kasper Bågmark DTSTART:20260128T153000Z DTEND:20260128T160000Z DTSTAMP:20260422T225820Z UID:gbgphd/30 DESCRIPTION:Title: A fractal paradox on how to measure: From coastlines to stochastic process es\nby Kasper Bågmark as part of Gothenburg PhD seminar\n\nLecture he ld in MVL14.\n\nAbstract\nHow long is a coastline? The inconvenient truth is that it depends on your ruler. Beginning with this paradox\, we take a relaxed tour of fractal geometry\, moving from tidy deterministic fractals like Cantor sets and Sierpiński triangles to the much rougher random fra ctals that arise in stochastic processes.\n LOCATION:https://researchseminars.org/talk/gbgphd/30/ END:VEVENT BEGIN:VEVENT SUMMARY:Erik Jansson DTSTART:20260204T153000Z DTEND:20260204T160000Z DTSTAMP:20260422T225820Z UID:gbgphd/31 DESCRIPTION:Title: Some recent developments since my last talk in this series\nby Erik Ja nsson as part of Gothenburg PhD seminar\n\nLecture held in MVL14.\n\nAbstr act\nIn my last talk in this seminar series\, I discussed a method for com puting the polar factorization of matrix in a manner that is neither fast nor efficient. Since then\, there have been developments that are not rela ted to that project at all. In this talk\, I will discuss some of these de velopments in varying degree of detail.\n LOCATION:https://researchseminars.org/talk/gbgphd/31/ END:VEVENT BEGIN:VEVENT SUMMARY:Albert Vesterlund DTSTART:20260302T153000Z DTEND:20260302T160000Z DTSTAMP:20260422T225820Z UID:gbgphd/36 DESCRIPTION:Title: Solving* $\\mathcal{NP}$-problems in polynomial time\nby Albert Vester lund as part of Gothenburg PhD seminar\n\nLecture held in MVL14.\n\nAbstra ct\nWhile there exist problems which cannot be solved in polynomial time ( unless $\\mathcal P = \\mathcal {NP}$)\, one might naturally ponder the qu estion "How close can we get to the solution?".\nAs it turns out\, the ans wer is closer than you might initially think.\nIn this talk\, I will give a brief insight into the world of Approximation Algorithms\, while also sh owing you how to solve* the problem of packing your suitcases before a fli ght!\n(*almost)\n LOCATION:https://researchseminars.org/talk/gbgphd/36/ END:VEVENT BEGIN:VEVENT SUMMARY:Jenny Enerbäck DTSTART:20260223T153000Z DTEND:20260223T160000Z DTSTAMP:20260422T225820Z UID:gbgphd/40 DESCRIPTION:Title: What is the problem with generalized eigenvalue problems?\nby Jenny En erbäck as part of Gothenburg PhD seminar\n\nLecture held in MVL14.\n\nAbs tract\nWhat are generalized problems about? How are they different from "n ormal" eigenvalue problems? And what could go wrong...? All this\, and mor e\, Monday afternoon!\n LOCATION:https://researchseminars.org/talk/gbgphd/40/ END:VEVENT BEGIN:VEVENT SUMMARY:Gustav Mårdby (Chalmers University of Technology) DTSTART:20260401T143000Z DTEND:20260401T150000Z DTSTAMP:20260422T225820Z UID:gbgphd/41 DESCRIPTION:Title: Strict Tessellations of Polytopes: From Polygons to Higher Dimensions\ nby Gustav Mårdby (Chalmers University of Technology) as part of Gothenbu rg PhD seminar\n\nLecture held in MVL14.\n\nAbstract\nStrict tessellations occur when copies of a polytope tile Euclidean space in a very special wa y. In this talk\, we ask: which polytopes admit such tessellations? We pre sent the complete classification in two dimensions and indicate how the pr oblem extends to higher dimensions. Finally\, we explain how these polytop es naturally appear in spectral geometry.\n LOCATION:https://researchseminars.org/talk/gbgphd/41/ END:VEVENT BEGIN:VEVENT SUMMARY:Philipp Misof (Chalmers/GU & Genentech/Roche) DTSTART:20260420T143000Z DTEND:20260420T150000Z DTSTAMP:20260422T225820Z UID:gbgphd/42 DESCRIPTION:Title: What the FOMO in AI for drug discovery is about\nby Philipp Misof (Cha lmers/GU & Genentech/Roche) as part of Gothenburg PhD seminar\n\nLecture h eld in MVL14.\n\nAbstract\nAfter having spent about eight months doing a r esearch internship in the pharma industry\, I want to share my experience of quite a different world compared to academia. I will give an overview o f the Nobel-prize-winning AlphaFold model - an AI that predicts protein st ructures - discuss the hype it caused in biotech\, and why even TikTok has a connection to this topic.\n LOCATION:https://researchseminars.org/talk/gbgphd/42/ END:VEVENT BEGIN:VEVENT SUMMARY:Ruben Seyer (Chalmers University of Technology & University of Got henburg) DTSTART:20260429T143000Z DTEND:20260429T150000Z DTSTAMP:20260422T225820Z UID:gbgphd/45 DESCRIPTION:Title: This Fortress Built by Nature for Herself… and Extended by Concrete\ nby Ruben Seyer (Chalmers University of Technology & University of Gothenb urg) as part of Gothenburg PhD seminar\n\nLecture held in MVL14.\n\nAbstra ct\nIn which I spend two months in England: surviving life as a PhD studen t at Warwick in the first-year ghetto\, blagging my way into a completely random Oxford formal\, accidentally discovering how to commit criminal tre spass in Bristol\, proving that the British train network’s “cost metr ic” is not\, in fact\, a metric\, and settling the question of which pub in Cambridge is actually the best.\n LOCATION:https://researchseminars.org/talk/gbgphd/45/ END:VEVENT BEGIN:VEVENT SUMMARY:Gijs Custers DTSTART:20260513T143000Z DTEND:20260513T150000Z DTSTAMP:20260422T225820Z UID:gbgphd/47 DESCRIPTION:by Gijs Custers as part of Gothenburg PhD seminar\n\nLecture h eld in MVL14.\nAbstract: TBA\n LOCATION:https://researchseminars.org/talk/gbgphd/47/ END:VEVENT BEGIN:VEVENT SUMMARY:Mathis Rost (PhD student) DTSTART:20260409T143000Z DTEND:20260409T150000Z DTSTAMP:20260422T225820Z UID:gbgphd/49 DESCRIPTION:Title: Wildfire Forecasting with Point Processes\nby Mathis Rost (PhD student ) as part of Gothenburg PhD seminar\n\nLecture held in MVL14.\n\nAbstract\ nWe develop a spatio-temporal Hawkes model for wildfire spread in Sicily o ver the period 2001--2025\, with particular focus on a covariate-dependent branching ratio that quantifies the strength of self-excitation. The moti vating idea is that\, conditional on an initial fire\, subsequent ignition s and detections are generated through a spread mechanism whose intensity varies with environmental conditions. Since satellite detections are obser ved only burstwise at irregular overpass times\, standard continuous-time inference is not directly applicable. We therefore make use of the branchi ng representation of the Hawkes process and assume that each ignition can be linked to its fire of origin\, yielding a practical basis for inference from clustered overpass data. The resulting framework allows the triggeri ng intensity to depend on meteorological covariates\, fire-weather indices \, local fuel composition\, and topography.\n LOCATION:https://researchseminars.org/talk/gbgphd/49/ END:VEVENT BEGIN:VEVENT SUMMARY:Edvin Martinson DTSTART:20260416T143000Z DTEND:20260416T150000Z DTSTAMP:20260422T225820Z UID:gbgphd/50 DESCRIPTION:Title: Naked Singularities in Your Area — Click to Apply Cosmic Censorship\ nby Edvin Martinson as part of Gothenburg PhD seminar\n\nLecture held in M VL14.\n\nAbstract\nA brief history of general relativity\, with particular emphasis on causality\, black holes and cosmic censorship\, followed by s ome non-rigorous results suggesting that Vlasov matter could help clothe s ome otherwise naked (and rather dusty) singularities.\n LOCATION:https://researchseminars.org/talk/gbgphd/50/ END:VEVENT BEGIN:VEVENT SUMMARY:Adrien Malacan DTSTART:20260506T143000Z DTEND:20260506T150000Z DTSTAMP:20260422T225820Z UID:gbgphd/52 DESCRIPTION:Title: How to beat the Casino and know when your Code has converged : Mixing Time s of Markov Chains\nby Adrien Malacan as part of Gothenburg PhD semina r\n\nLecture held in MVL14.\n\nAbstract\nI invite you to read the category that fits you best.\n\nYou are a statistician : You deal with scarry dist ributions which you sample using MCMCs. But how do you know when your algo rithm has actually converged ? \n\nYou are a probabilist : The ergodic the orem tells you kindly that your favorite Markov chain converges to station arity...eventually. But it stays silent about when that happens. \n\nYou a re about to bet your mortgage in Las Vegas: Is the deck of cards the croup ier is shuffling really that random\; or is there an opportunity to mathem atically beat the casino ? \n\nIf at least one of these questions raises your interest\, you're välkommen to hear more about mixing times! :)\n LOCATION:https://researchseminars.org/talk/gbgphd/52/ END:VEVENT BEGIN:VEVENT SUMMARY:Robin van Haastrecht DTSTART:20260521T143000Z DTEND:20260521T150000Z DTSTAMP:20260422T225820Z UID:gbgphd/53 DESCRIPTION:by Robin van Haastrecht as part of Gothenburg PhD seminar\n\nL ecture held in MVL14.\nAbstract: TBA\n LOCATION:https://researchseminars.org/talk/gbgphd/53/ END:VEVENT END:VCALENDAR