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BEGIN:VEVENT
SUMMARY:Erik Jansson
DTSTART:20241211T150000Z
DTEND:20241211T160000Z
DTSTAMP:20260404T111213Z
UID:gbgphd/1
DESCRIPTION:Title: An actual real-life application of geodesic equations on Lie groups:
proteins\nby Erik Jansson as part of Gothenburg PhD seminar\n\nLectur
e held in MVL15.\n\nAbstract\nWhat is in the intersection of optimization\
, geometric mechanics and protein imaging? The contents of this talk! I ha
ve studied how to solve the problem of reconstructing protein conformation
s from very noisy electron microscopy images\, using techniques from geome
tric shape matching. By deforming an initial template using the action of
a suitable Lie group in an optimal way\, we can reconstruct the indirectly
observed target conformation of the protein. In this talk\, I hope to int
roduce you to the beautiful concept of shape matching in a way that is FUN
(Friendly Understanding for Novices). References will be provided for tho
se looking to learn more.\n
LOCATION:https://stable.researchseminars.org/talk/gbgphd/1/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Mattias Byléhn
DTSTART:20241216T143000Z
DTEND:20241216T153000Z
DTSTAMP:20260404T111213Z
UID:gbgphd/2
DESCRIPTION:Title: One or two perspectives on the Heisenberg group\nby Mattias Byl
éhn as part of Gothenburg PhD seminar\n\nLecture held in MVL14.\n\nAbstra
ct\nMy aim with this talk is to illustrate the versatility of the Schrödi
nger representation of the Heisenberg group. I will try to motivate its ex
istence from a simple inverse problem for radars\, and if there is time th
en I will also explain some connections to theta functions in analytic num
ber theory. No prior knowledge of any of these things will be assumed.\n
LOCATION:https://stable.researchseminars.org/talk/gbgphd/2/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Ruben Seyer (Chalmers/GU)
DTSTART:20250123T153000Z
DTEND:20250123T160000Z
DTSTAMP:20260404T111213Z
UID:gbgphd/3
DESCRIPTION:Title: Non-reversible Markov samplers and parallel universes\nby Ruben
Seyer (Chalmers/GU) as part of Gothenburg PhD seminar\n\nLecture held in M
VL14.\n\nAbstract\nWherein I try to make you see the light of Bayesian sta
tistics\, its practical applications\, and we look at a few vignettes of m
y past and current projects.\n
LOCATION:https://stable.researchseminars.org/talk/gbgphd/3/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Styrbjörn Käll
DTSTART:20250131T150000Z
DTEND:20250131T153000Z
DTSTAMP:20260404T111213Z
UID:gbgphd/4
DESCRIPTION:Title: Chemical hazards from the tip of the iceberg\nby Styrbjörn Käl
l as part of Gothenburg PhD seminar\n\nLecture held in MVL14.\n\nAbstract\
nEnvironmental hazard assessments are reliant on toxicity data that cover
multiple organism groups. Generating experimental toxicity data is\, howev
er\, resource-intensive and time-consuming. Computational methods are fast
and cost-efficient alternatives\, but the low accuracy and narrow applica
bility domains have made their adaptation slow. In this presentation\, we
will learn the basics of chemical hazard assessment\, talk briefly about c
heminformatics\, and finally build intuition for why transformers are suit
able models for capturing the complex chemical and biological interactions
necessary for accurate toxicity prediction. Finally\, we will look at som
e results from our recent publication\, demonstrating how transformers cap
ture toxicity-specific features directly from the chemical structures them
selves.\n
LOCATION:https://stable.researchseminars.org/talk/gbgphd/4/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Rickard Cullman
DTSTART:20250213T153000Z
DTEND:20250213T160000Z
DTSTAMP:20260404T111213Z
UID:gbgphd/5
DESCRIPTION:Title: A taste of Ergodic Ramsey theory\nby Rickard Cullman as part of
Gothenburg PhD seminar\n\nLecture held in MVL14.\n\nAbstract\nErgodic Rams
ey theory is a branch of mathematics that\, loosely speaking\, applies Erg
odic theory (measurable dynamics) to the study of certain number-theoretic
problems. \n\nIn this talk I will give a quick introduction to both Ramse
y theory and Ergodic theory\, and how the two relate via the Furstenberg c
orrespondence principle. I will conclude with a brief discussion of Szemer
edi's theorem on arithmetic progressions (often considered a highlight of
20:th century mathematics) and Furstenberg's ergodic-theoretic proof of it
. I aim to convey how seemingly very abstract mathematical methods from me
asure theory and functional analysis can be used to prove easily formulate
d number-theoretic statements.\n
LOCATION:https://stable.researchseminars.org/talk/gbgphd/5/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Anna Theorin Johansson
DTSTART:20250220T153000Z
DTEND:20250220T160000Z
DTSTAMP:20260404T111213Z
UID:gbgphd/6
DESCRIPTION:Title: Zaremba's conjecture and the circle method\nby Anna Theorin Joha
nsson as part of Gothenburg PhD seminar\n\nLecture held in MVL14.\n\nAbstr
act\nZaremba's conjecture from 1971 states that every natural number is th
e denominator of a reduced fraction for which the partial quotients in its
continued fraction expansion are bounded by an absolute constant. I will
try to describe the motivation behind the problem and present some partial
progress towards the conjecture.\n
LOCATION:https://stable.researchseminars.org/talk/gbgphd/6/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Elias Nyholm
DTSTART:20250227T153000Z
DTEND:20250227T160000Z
DTSTAMP:20260404T111213Z
UID:gbgphd/7
DESCRIPTION:Title: Geometric deep learning\; or\, processing pictures of cute dogs usin
g differential geometry\nby Elias Nyholm as part of Gothenburg PhD sem
inar\n\nLecture held in MVL14.\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/gbgphd/7/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Robin van Haastrecht (GU/Chalmers)
DTSTART:20250304T153000Z
DTEND:20250304T160000Z
DTSTAMP:20260404T111213Z
UID:gbgphd/8
DESCRIPTION:Title: The Wehrl inequality: the creation of a pure math conjecture\nby
Robin van Haastrecht (GU/Chalmers) as part of Gothenburg PhD seminar\n\nL
ecture 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 quantum mechanics. He conjectured a condition for when this entropy is
minimized\, and this conjecture was proved shortly thereafter by Lieb\, w
ho extended it to a more general context. This gave rise to an interesting
area of mathematical research. I will give a historical background and an
overview of the main problem\n
LOCATION:https://stable.researchseminars.org/talk/gbgphd/8/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Julia Jansson
DTSTART:20250403T143000Z
DTEND:20250403T150000Z
DTSTAMP:20260404T111213Z
UID:gbgphd/9
DESCRIPTION:Title: My research visit to UCLA\nby Julia Jansson as part of Gothenbur
g PhD seminar\n\nLecture held in MVL14.\n\nAbstract\nI will present my exp
erience during my research visit at UCLA including more informal aspects l
ike pros and cons\, PhD life in the US and life in LA. Then\, without goin
g 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. L
astly I will also mention how to finance a research stay using travel gran
ts.\n
LOCATION:https://stable.researchseminars.org/talk/gbgphd/9/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Jakob Jonsson
DTSTART:20250410T143000Z
DTEND:20250410T150000Z
DTSTAMP:20260404T111213Z
UID:gbgphd/10
DESCRIPTION:Title: The Whitney Method of Fundamental Solutions\nby Jakob Jonsson a
s part of Gothenburg PhD seminar\n\nLecture held in MVL14.\nAbstract: TBA\
n
LOCATION:https://stable.researchseminars.org/talk/gbgphd/10/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Philipp Misof
DTSTART:20250416T143000Z
DTEND:20250416T150000Z
DTSTAMP:20260404T111213Z
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\
nLecture held in MVL14.\n\nAbstract\nDue to the current boom in AI\, deep
learning has become mainstream. The name is inspired by the fact that the
corresponding machine learning models are usually a composition of many la
yers of parametrized transformations. To swim against (or arguably orthogo
nal to) the tide\, what happens if we instead consider particularly 𝘸
𝘪𝘥𝘦 layers? In this talk\, I will present the spherical cow equiv
alent of neural networks and how this spherical cow can even be endowed wi
th additional symmetry\, like 3d rotations (... the analogy may be lacking
).\n
LOCATION:https://stable.researchseminars.org/talk/gbgphd/11/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Björn Müller
DTSTART:20250508T143000Z
DTEND:20250508T150000Z
DTSTAMP:20260404T111213Z
UID:gbgphd/12
DESCRIPTION:Title: A visual walk through modelling stochastically evolving surfaces by
SPDEs\nby Björn Müller as part of Gothenburg PhD seminar\n\nLecture
held in MVL14.\n\nAbstract\nThe seal (TM) will guide you on a journey fro
m stochastic processes on the unit sphere\, via solving SPDEs using spectr
al methods\, all the way to a variety of shape-shifting stochastic surface
s.\nTogether\, we will explore how such surfaces arise from their building
blocks and what we can learn about their shapes and shape-shifting ("Höl
der regularity").\nLet yourself be fascinated by the wide range of applica
tions of these shape-shifters.\n\nSo sit back\, relax and enjoy an afterno
on of amazing imagery and seizure-inducing videos!\n
LOCATION:https://stable.researchseminars.org/talk/gbgphd/12/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Jan Gundelach (University of Gothenburg)
DTSTART:20250327T153000Z
DTEND:20250327T160000Z
DTSTAMP:20260404T111213Z
UID:gbgphd/13
DESCRIPTION:Title: What are groupoids?\nby Jan Gundelach (University of Gothenburg
) as part 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
together just to exhibit a total lack of applications! Don't miss pimped a
lgebraic concepts disguised as a zoo of cute animals\, a lot of wild arrow
s\, sporadic French vocabulary\, and mysterious convoluted algebras!\n
LOCATION:https://stable.researchseminars.org/talk/gbgphd/13/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Adélie Erard (Paris Cité University)
DTSTART:20250527T143000Z
DTEND:20250527T150000Z
DTSTAMP:20260404T111213Z
UID:gbgphd/14
DESCRIPTION:Title: Modeling fine-scale abundance dynamics: a dual frequentist and Baye
sian approach applied to common birds\nby Adélie Erard (Paris Cité U
niversity) as part of Gothenburg PhD seminar\n\nLecture held in MVL14.\n\n
Abstract\nUnderstanding how animal populations grow and change at a local
scale is key to studying ecosystems and supporting conservation efforts. I
n this study\, we explore two complementary methods to analyze data from t
he French Common Birds Monitoring Program (STOC).\n\nThe first method uses
a statistical model that views population changes as driven by births and
deaths\, influenced by how individuals interact with each other and by en
vironmental factors like climate and landscape. One major challenge is tha
t these interactions often depend on spatial location and that the data ar
e partly random. To address this\, we develop new ways to estimate birth a
nd death patterns and use a mathematical theory (called stabilization) tha
t assumes interactions mostly happen at a local scale. This helps ensure t
hat our estimates are accurate and reliable when predicting changes in bir
d numbers at specific locations.\n\nThe second method uses a Bayesian spat
io-temporal model\, estimated with a technique called INLA (Integrated Nes
ted Laplace Approximation). This model takes into account both space and t
ime\, helping us measure how environmental variables affect bird populatio
ns over time. It includes spatial patterns modeled through differential eq
uations\, time trends using autoregressive effects\, and different respons
es depending on habitat type.\n
LOCATION:https://stable.researchseminars.org/talk/gbgphd/14/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Lotta Eriksson
DTSTART:20250424T143000Z
DTEND:20250424T150000Z
DTSTAMP:20260404T111213Z
UID:gbgphd/15
DESCRIPTION:Title: Tracking of cancer using blood samples\nby Lotta Eriksson as pa
rt of Gothenburg PhD seminar\n\nLecture held in MVL14.\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/gbgphd/15/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Gustav Mårdby (Chalmers University of Technology)
DTSTART:20250515T143000Z
DTEND:20250515T150000Z
DTSTAMP:20260404T111213Z
UID:gbgphd/16
DESCRIPTION:Title: Can one hear the shape of a drum? A glimpse into spectral geometry
and flat tori\nby Gustav Mårdby (Chalmers University of Technology) a
s part of Gothenburg PhD seminar\n\nLecture held in MVL15.\n\nAbstract\nWh
at can the sound of a drum tell us about its shape? This simple-sounding q
uestion\, famously posed by Mark Kac in 1966\, lies at the heart of spectr
al geometry - a field that explores how the eigenvalues of the Laplacian r
elate to the geometry of a space. In this talk\, we'll look at what inform
ation can and cannot be recovered from the spectrum\, guided by classical
results\, clever counterexamples\, and a few open problems. We'll then foc
us on the case of flat tori\, where many of these results become particula
rly elegant (and sometimes surprisingly tricky). In the end\, I will prese
nt a new result: a 6-dimensional triplet of isospectral\, non-isometric fl
at tori. No prior knowledge is expected - just bring your curiosity!\n
LOCATION:https://stable.researchseminars.org/talk/gbgphd/16/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Mathis Rost (PhD student)
DTSTART:20250522T143000Z
DTEND:20250522T150000Z
DTSTAMP:20260404T111213Z
UID:gbgphd/17
DESCRIPTION:Title: A Brief Introduction to Spatial Point Processes\nby Mathis Rost
(PhD student) as part of Gothenburg PhD seminar\n\nLecture held in MVL14.
\n\nAbstract\nIn this talk\, I’ll give a brief and\, of course\, mostly
visually pleasing introduction to my research area: spatial statistics. We
’ll begin with some general characteristics and a few real-world example
s where point process models naturally arise. I’ll then introduce some k
ey concepts\, like intensity-based models and conditional intensity-based
models\, which form the backbone of spatial statistics. Toward the end\, I
’ll touch on one of the topics from my first research paper (don’t wor
ry\, I’ll keep the math simple!).\n
LOCATION:https://stable.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:20260404T111213Z
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 part 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 we
ll-known problem that mathematics is easy but politics is difficult.\nElec
toral mathematics is concerned with constructing algorithms that convert v
ote counts to seat counts. Unfortunately\, nobody can agree on what makes
such an algorithm "fair".\nWe review some famous theorems that show why.\n
We also review divisor methods\, in use in most proportional elections. Th
ese satisfy certain satisfying theorems which may be indicative of their "
fairness".\nFinally\, we consider some takeover attacks in local councils
possible due to mathematical deficiencies in the Swedish electoral system
highlighted by Janson & Linusson (2022).\n
LOCATION:https://stable.researchseminars.org/talk/gbgphd/18/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Erik Jansson
DTSTART:20250918T143000Z
DTEND:20250918T150000Z
DTSTAMP:20260404T111213Z
UID:gbgphd/19
DESCRIPTION:Title: How to compute the polar factorization of a matrix in a way you sho
uldn't\nby Erik Jansson as part of Gothenburg PhD seminar\n\nLecture h
eld 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-def
inite symmetric factor. There exist various ways to do this fast and effic
iently\, but in this talk\, I would like to present a method that is neith
er fast nor efficient. In fact\, it is completely inadvisable and should n
ot be used for any application relying in any way on computing the polar f
actorization. It is\, however\, interesting for an entirely different reas
on\, in that it arises in an unexpected and fascinating way. \nAfter havin
g showcased the method\, I will briefly explain its derivation by discussi
ng the Gaussian optimal transport problem\, principal fiber bundles\, and
gradient flows to showcase that even numerical linear algebra can have dee
p geometric roots.\n
LOCATION:https://stable.researchseminars.org/talk/gbgphd/19/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Anna Theorin Johansson
DTSTART:20250925T143000Z
DTEND:20250925T150000Z
DTSTAMP:20260404T111213Z
UID:gbgphd/21
DESCRIPTION:Title: Draw me if you can: Constructions with Euclidean tools\nby Anna
Theorin Johansson as part of Gothenburg PhD seminar\n\nLecture held in MV
L14.\n\nAbstract\nHow much geometry can you squeeze out of a straightedge
and compass? Trisect an angle? Maybe not. Draw a regular 17-gon? Absolutel
y. The ancient Greeks figured out how to draw sums\, differences\, product
s\, ratios and square roots of given lengths\, as well as how to construct
some geometric figures from others\, but it took two millennia to finally
completely close the case of constructible polygons. In this filler episo
de\, we’ll cover the main ideas: which shapes can be drawn\, which can
’t\, and why.\n
LOCATION:https://stable.researchseminars.org/talk/gbgphd/21/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Adrien Malacan
DTSTART:20251120T150000Z
DTEND:20251120T153000Z
DTSTAMP:20260404T111213Z
UID:gbgphd/23
DESCRIPTION:Title: The Curie point and the Ising model : when spins rebel.\nby Adr
ien Malacan as part of Gothenburg PhD seminar\n\nLecture held in MVL14.\n\
nAbstract\nLet's do a home experiment.\n\nTake two magnetized pieces of ir
on stuck together (everyone has a pair lying around at home). Now\, simply
heat them to about 770°C\, or 1043 K\, for the SI purists. Surprise: the
two pieces 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 will see why probability theory saw this coming - and why this exact t
emperature is less random than you might think.\n
LOCATION:https://stable.researchseminars.org/talk/gbgphd/23/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Albert Vesterlund
DTSTART:20251009T143000Z
DTEND:20251009T150000Z
DTSTAMP:20260404T111213Z
UID:gbgphd/24
DESCRIPTION:Title: Packing my $\\mathcal{NP}$-complete suitcase(s)\nby Albert Vest
erlund as part of Gothenburg PhD seminar\n\nLecture held in MVL14.\n\nAbst
ract\nHave you ever wondered why packing your infinite amount of suitcases
optimally can be such a time-consuming task? Or perhaps you have simply e
njoyed a game of Tetris at one point in your life? In any case\, you have
most likely 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 will see what a packing problem actually is\, and why they are such a
mess in practice.\n
LOCATION:https://stable.researchseminars.org/talk/gbgphd/24/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Robin van Haastrecht
DTSTART:20251024T133000Z
DTEND:20251024T140000Z
DTSTAMP:20260404T111213Z
UID:gbgphd/25
DESCRIPTION:Title: How to eat a pizza\nby Robin van Haastrecht as part of Gothenbu
rg PhD seminar\n\nLecture held in MVL14.\n\nAbstract\nA talk on Gauss's th
eorema egregium\, curvature and hopefully some hyperbolic geometry.\n
LOCATION:https://stable.researchseminars.org/talk/gbgphd/25/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Mathis Rost (PhD student)
DTSTART:20251204T153000Z
DTEND:20251204T160000Z
DTSTAMP:20260404T111213Z
UID:gbgphd/26
DESCRIPTION:Title: A Month in Paris and some Spatial Mixing\nby Mathis Rost (PhD s
tudent) as part of Gothenburg PhD seminar\n\nLecture held in MVL14.\n\nAbs
tract\nIn November I spent a research visit in Paris at MAP5 and Inria\, w
here between cafés\, croissants\, and getting lost in charming side stree
ts\, 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 i
s spatial mixing in Gibbs point processes and spatial birth–death proces
ses.\n\nWe’ll first discuss what spatial mixing and ergodicity mean in t
he context of point processes. Then we’ll see why establishing mixing fo
r Gibbs processes is notoriously difficult\, and how this motivates lookin
g instead at spatial birth–death processes\, where such properties can b
e shown much more easily.\n
LOCATION:https://stable.researchseminars.org/talk/gbgphd/26/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Lotta Eriksson
DTSTART:20251106T153000Z
DTEND:20251106T160000Z
DTSTAMP:20260404T111213Z
UID:gbgphd/27
DESCRIPTION:Title: The Galton-Watson process and aging cells\nby Lotta Eriksson as
part of Gothenburg PhD seminar\n\nLecture held in MVL14.\n\nAbstract\nThe
Galton–Watson process was developed to explore the possible extinction
of family names\, sparked by a Victorian worry that aristocratic surnames
were slowly dying out. The Galton–Watson process models how populations
evolve across generations\, where each individual produces a random number
of offspring. In a multitype Galton-Watson process we allow the individua
ls to be of different type to allow for different probabilistic behavior.
In this talk\, I present a multitype Galton-Watson process to model popula
tions of cells that ages biologically by accumulating damage within the ce
ll body. The cells have the ability to pass on part of its damage to its d
aughter cell\, resulting in rejuvenation and longer life spans. Furthermor
e\, I present how we can model a single cell using Markov chains.\n
LOCATION:https://stable.researchseminars.org/talk/gbgphd/27/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Joseph Löfving
DTSTART:20251208T153000Z
DTEND:20251208T160000Z
DTSTAMP:20260404T111213Z
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 i
n MVL14.\n\nAbstract\nThe Guinness Book of World Records lists the record
for fastest journey between every station on the London Underground as 17
hours\, 46 minutes and 48 seconds. Gothenburg\, being colloquially known a
s "Little London"\, of course deserves a little record of its own\, substi
tuting the underground for the tram network. This record is—to the speak
er's knowledge—currently held by two boys in their younger teens\, who c
laim a time of 5 hours and 19 minutes. In this talk\, we use mathematical
optimization techniques and a high-performance computing cluster to crush
the dreams of these two boys and claim the record for ourselves.\n\nJoin m
e as I develop Ruben on Rails¹\, an algorithm that finds the fastest jour
ney passing all tram stops in a given day. During the talk\, we will see a
dvanced optimization techniques such as establishing dominance\, solving t
he wrong problem\, and ignoring nearly all of Hisingen—all employed in t
he endeavor to spend several consecutive hours on public transport "effici
ently".\n\n\n\n¹Since the topic (trams) is quintessentially Gothenburgian
\, it is only fitting that the algorithm has a name in the form of a Gothe
nburgian pun. Now\, one shouldn't explain their jokes\, but I am too proud
of this one\, and it is somewhat niche\, so I'll break that rule: there i
s a web application framework called Ruby on Rails\, and this work was don
e with—and initiated by—our very own Ruben Seyer\, hence Ruben on Rail
s. Not that web application frameworks are at all relevant here. Anyway\,
I think this is hilarious\, and will gladly accept compliments for my come
dic genius in written or oral form.\n
LOCATION:https://stable.researchseminars.org/talk/gbgphd/28/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Michael Roop
DTSTART:20251218T153000Z
DTEND:20251218T160000Z
DTSTAMP:20260404T111213Z
UID:gbgphd/29
DESCRIPTION:Title: What are solutions to O(P)DEs?\nby Michael Roop as part of Goth
enburg 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 diffe
rential equations. This theory makes rigorous sense of multivalued solutio
ns to both ordinary and partial differential equations\, which serve as an
alternative to weak solutions developed in the functional analytic framew
ork.\nThis is the only theory (I am aware of) that formulates precise suff
icient conditions for integrability of general type ODEs (sort of “Galoi
s theory” for ODEs) in terms properties of their symmetry group. This re
sult is known as the Lie-Bianchi theorem. Its particular case is the celeb
rated Liouville-Arnold theorem on integrability of Hamiltonian systems. If
time permits (likely\, not)\, we will also see applications of this theor
y in different areas: hydrodynamics\, Monge-Ampère equations\, classifica
tion problems in algebra.\n
LOCATION:https://stable.researchseminars.org/talk/gbgphd/29/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Kasper Bågmark
DTSTART:20260128T153000Z
DTEND:20260128T160000Z
DTSTAMP:20260404T111213Z
UID:gbgphd/30
DESCRIPTION:Title: A fractal paradox on how to measure: From coastlines to stochastic
processes\nby Kasper Bågmark as part of Gothenburg PhD seminar\n\nLec
ture held 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 f
ractals like Cantor sets and Sierpiński triangles to the much rougher ran
dom fractals that arise in stochastic processes.\n
LOCATION:https://stable.researchseminars.org/talk/gbgphd/30/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Erik Jansson
DTSTART:20260204T153000Z
DTEND:20260204T160000Z
DTSTAMP:20260404T111213Z
UID:gbgphd/31
DESCRIPTION:Title: Some recent developments since my last talk in this series\nby
Erik Jansson as part of Gothenburg PhD seminar\n\nLecture held in MVL14.\n
\nAbstract\nIn my last talk in this seminar series\, I discussed a method
for computing the polar factorization of matrix in a manner that is neithe
r fast nor efficient. Since then\, there have been developments that are n
ot related to that project at all. In this talk\, I will discuss some of t
hese developments in varying degree of detail.\n
LOCATION:https://stable.researchseminars.org/talk/gbgphd/31/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Albert Vesterlund
DTSTART:20260302T153000Z
DTEND:20260302T160000Z
DTSTAMP:20260404T111213Z
UID:gbgphd/36
DESCRIPTION:Title: Solving* $\\mathcal{NP}$-problems in polynomial time\nby Albert
Vesterlund as part of Gothenburg PhD seminar\n\nLecture held in MVL14.\n\
nAbstract\nWhile there exist problems which cannot be solved in polynomial
time (unless $\\mathcal P = \\mathcal {NP}$)\, one might naturally ponder
the question "How close can we get to the solution?".\nAs it turns out\,
the answer is closer than you might initially think.\nIn this talk\, I wil
l give a brief insight into the world of Approximation Algorithms\, while
also showing you how to solve* the problem of packing your suitcases befor
e a flight!\n(*almost)\n
LOCATION:https://stable.researchseminars.org/talk/gbgphd/36/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Jenny Enerbäck
DTSTART:20260223T153000Z
DTEND:20260223T160000Z
DTSTAMP:20260404T111213Z
UID:gbgphd/40
DESCRIPTION:Title: What is the problem with generalized eigenvalue problems?\nby J
enny Enerbäck as part of Gothenburg PhD seminar\n\nLecture held in MVL14.
\n\nAbstract\nWhat are generalized problems about? How are they different
from "normal" eigenvalue problems? And what could go wrong...? All this\,
and more\, Monday afternoon!\n
LOCATION:https://stable.researchseminars.org/talk/gbgphd/40/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Gustav Mårdby (Chalmers University of Technology)
DTSTART:20260401T143000Z
DTEND:20260401T150000Z
DTSTAMP:20260404T111213Z
UID:gbgphd/41
DESCRIPTION:Title: Strict Tessellations of Polytopes: From Polygons to Higher Dimensio
ns\nby Gustav Mårdby (Chalmers University of Technology) as part of G
othenburg PhD seminar\n\nLecture held in MVL14.\n\nAbstract\nStrict tessel
lations occur when copies of a polytope tile Euclidean space in a very spe
cial way. In this talk\, we ask: which polytopes admit such tessellations?
We present the complete classification in two dimensions and indicate how
the problem extends to higher dimensions. Finally\, we explain how these
polytopes naturally appear in spectral geometry.\n
LOCATION:https://stable.researchseminars.org/talk/gbgphd/41/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Philipp Misof
DTSTART:20260420T143000Z
DTEND:20260420T150000Z
DTSTAMP:20260404T111213Z
UID:gbgphd/42
DESCRIPTION:by Philipp Misof as part of Gothenburg PhD seminar\n\nLecture
held in MVL14.\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/gbgphd/42/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Ruben Seyer
DTSTART:20260429T143000Z
DTEND:20260429T150000Z
DTSTAMP:20260404T111213Z
UID:gbgphd/45
DESCRIPTION:by Ruben Seyer as part of Gothenburg PhD seminar\n\nLecture he
ld in MVL14.\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/gbgphd/45/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Gijs Custers
DTSTART:20260513T143000Z
DTEND:20260513T150000Z
DTSTAMP:20260404T111213Z
UID:gbgphd/47
DESCRIPTION:by Gijs Custers as part of Gothenburg PhD seminar\n\nLecture h
eld in MVL14.\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/gbgphd/47/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Mathis Rost (PhD student)
DTSTART:20260409T143000Z
DTEND:20260409T150000Z
DTSTAMP:20260404T111213Z
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\nAb
stract\nWe develop a spatio-temporal Hawkes model for wildfire spread in S
icily over the period 2001--2025\, with particular focus on a covariate-de
pendent branching ratio that quantifies the strength of self-excitation. T
he motivating idea is that\, conditional on an initial fire\, subsequent i
gnitions and detections are generated through a spread mechanism whose int
ensity varies with environmental conditions. Since satellite detections ar
e observed only burstwise at irregular overpass times\, standard continuou
s-time inference is not directly applicable. We therefore make use of the
branching representation of the Hawkes process and assume that each igniti
on can be linked to its fire of origin\, yielding a practical basis for in
ference from clustered overpass data. The resulting framework allows the t
riggering intensity to depend on meteorological covariates\, fire-weather
indices\, local fuel composition\, and topography.\n
LOCATION:https://stable.researchseminars.org/talk/gbgphd/49/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Edvin Martinson
DTSTART:20260416T143000Z
DTEND:20260416T150000Z
DTSTAMP:20260404T111213Z
UID:gbgphd/50
DESCRIPTION:by Edvin Martinson as part of Gothenburg PhD seminar\n\nLectur
e held in MVL14.\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/gbgphd/50/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Adrien Malacan
DTSTART:20260506T143000Z
DTEND:20260506T150000Z
DTSTAMP:20260404T111213Z
UID:gbgphd/52
DESCRIPTION:by Adrien Malacan as part of Gothenburg PhD seminar\n\nLecture
held in MVL14.\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/gbgphd/52/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Robin van Haastrecht
DTSTART:20260521T143000Z
DTEND:20260521T150000Z
DTSTAMP:20260404T111213Z
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://stable.researchseminars.org/talk/gbgphd/53/
END:VEVENT
END:VCALENDAR