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BEGIN:VEVENT
SUMMARY:Emine Yıldırım (Queen's University)
DTSTART:20200812T160000Z
DTEND:20200812T173000Z
DTSTAMP:20260404T131145Z
UID:UCGEN/1
DESCRIPTION:Title: Cluster Categories\nby Emine Yıldırım (Queen's University) as
part of UCGEN - Uluslararası Cebirsel GEometri Neşesi\n\n\nAbstract\nClu
ster Categories are introduced to understand cluster dynamics from the rep
resentation theory point of view. The subject has its roots in two importa
nt results in the literature that give us a glimpse of a relationship betw
een cluster dynamics and representation theory. The first is that there is
an one-to-one correspondence between the cluster variables of a finite ty
pe cluster algebra and the almost positive roots of the corresponding root
system. The second is a well-known result by Gabriel that classifies fini
te representation type quivers by using positive roots of the correspondin
g root system. In this talk\, after giving an overview of cluster categori
es\, I will talk about a recent joint work with Charles Paquette on the ge
neralization of discrete cluster categories.\n
LOCATION:https://stable.researchseminars.org/talk/UCGEN/1/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Emre Sertöz (Leibniz University Hannover)
DTSTART:20200819T160000Z
DTEND:20200819T173000Z
DTSTAMP:20260404T131145Z
UID:UCGEN/2
DESCRIPTION:Title: Separating periods of quartic surfaces\nby Emre Sertöz (Leibniz
University Hannover) as part of UCGEN - Uluslararası Cebirsel GEometri Ne
şesi\n\n\nAbstract\nKontsevich--Zagier periods form a natural number syst
em that extends the algebraic numbers by adding constants coming from geom
etry and physics. Because there are countably many periods\, one would exp
ect it to be possible to compute effectively in this number system. This w
ould require an effective height function and the ability to separate peri
ods of bounded height\, neither of which are currently possible.\n\nIn thi
s talk\, we introduce an effective height function for periods of quartic
surfaces defined over algebraic numbers. We also determine the minimal dis
tance between periods of bounded height on a single surface. We use these
results to prove heuristic computations of Picard groups that rely on appr
oximations of periods. Moreover\, we give explicit Liouville type numbers
that can not be the ratio of two periods of a quartic surface. This is ong
oing work with Pierre Lairez (Inria\, France).\n
LOCATION:https://stable.researchseminars.org/talk/UCGEN/2/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Yusuf Barış Kartal (Princeton University)
DTSTART:20200826T160000Z
DTEND:20200826T173000Z
DTSTAMP:20260404T131145Z
UID:UCGEN/3
DESCRIPTION:Title: p-adic analytic actions on Fukaya categories and iterates of symplect
omorphisms\nby Yusuf Barış Kartal (Princeton University) as part of
UCGEN - Uluslararası Cebirsel GEometri Neşesi\n\n\nAbstract\nA theorem o
f Bell\, Satriano and Sierra state that for a given smooth complex surface
$X$ with an automorphism $\\phi$ the set of natural numbers $n$ such that
$Ext^i(F\,(\\phi^*)^n(F'))\\neq 0$ is a union of finitely many arithmetic
progressions and finitely many other numbers. Due to homological mirror s
ymmetry conjecture\, one can expect a symplectic version of this statement
. In this talk\, we will present such a theorem for a class of symplectic
manifolds and symplectomorphisms isotopic to identity. The technique is an
alogous to its algebro-geometric counterpart: namely we construct p-adic a
nalytic action on a version of the Fukaya category\, interpolating the act
ion of the iterates of the symplectomorphism.\n
LOCATION:https://stable.researchseminars.org/talk/UCGEN/3/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Özge Ülkem (Heidelberg University)
DTSTART:20200902T160000Z
DTEND:20200902T173000Z
DTSTAMP:20260404T131145Z
UID:UCGEN/4
DESCRIPTION:Title: Uniformization of the moduli space of generalized $\\mathcal{D}$-ell
iptic sheaves\nby Özge Ülkem (Heidelberg University) as part of UCGE
N - Uluslararası Cebirsel GEometri Neşesi\n\n\nAbstract\nDrinfeld define
d the notion of elliptic modules\, which are now called Drinfeld modules\,
as an analogue of elliptic curves in the function field setting. To prove
the Langlands correspondence in this context\, Drinfeld studied moduli sp
aces of elliptic sheaves. The categories of elliptic sheaves and Drinfeld
modules are equivalent under certain conditions. Since then\, many general
izations of elliptic sheaves have been studied\, such as $\\mathcal{D}$-el
liptic sheaves defined by Laumon\, Rapoport and Stuhler and Frobenius-Heck
e sheaves defined by Stuhler. In this talk\, we will give a brief introduc
tion to the function field world and introduce a new generalization of ell
iptic sheaves\, called generalized $\\mathcal{D}$-elliptic sheaves. We wil
l state a uniformization theorem for the moduli space of the latter and ta
lk about the proof if time permits. This builds on work of Laumon-Rapoport
-Stuhler\, of Hartl and of Rapoport-Zink.\n
LOCATION:https://stable.researchseminars.org/talk/UCGEN/4/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Mehmet Kıral (RIKEN AIP)
DTSTART:20200909T160000Z
DTEND:20200909T173000Z
DTSTAMP:20260404T131145Z
UID:UCGEN/5
DESCRIPTION:Title: Kloosterman Sums for SL3 Long Word Element\nby Mehmet Kıral (RIK
EN AIP) as part of UCGEN - Uluslararası Cebirsel GEometri Neşesi\n\n\nAb
stract\nUsing the reduced word decomposition of the long word element of t
he Weyl group element of SL3\, we give a nice expression for the long word
Kloosterman sum. First classical Kloosterman sums\, their importance\, an
d matrix formulation will be introduced. This is joint work with Maki Naka
suji of Sophia University (Tokyo).\n
LOCATION:https://stable.researchseminars.org/talk/UCGEN/5/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Hülya Argüz (University of Versailles Saint-Quentin-En-Yvelines)
DTSTART:20200916T150000Z
DTEND:20200916T163000Z
DTSTAMP:20260404T131145Z
UID:UCGEN/6
DESCRIPTION:Title: An algebro-geometric view on mirror symmetry\nby Hülya Argüz (U
niversity of Versailles Saint-Quentin-En-Yvelines) as part of UCGEN - Ulus
lararası Cebirsel GEometri Neşesi\n\n\nAbstract\nMirror symmetry is a ph
enomenon discovered by string theorists\, which relates physical theories
obtained using different deformation families of Calabi-Yau manifolds. An
algebro--geometric approach to mirror symmetry\, which uses tropical and l
og geometric tools to construct such families of Calabi--Yau manifolds\, i
s provided by the Gross-Siebert program. In this talk we will review the m
ost recent advances in this program\, and particularly report on our joint
work with Mark Gross.\n
LOCATION:https://stable.researchseminars.org/talk/UCGEN/6/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Umut Varolgüneş (Stanford University)
DTSTART:20200923T160000Z
DTEND:20200923T173000Z
DTSTAMP:20260404T131145Z
UID:UCGEN/7
DESCRIPTION:Title: Homological mirror symmetry for chain type invertible polynomials
\nby Umut Varolgüneş (Stanford University) as part of UCGEN - Uluslarara
sı Cebirsel GEometri Neşesi\n\n\nAbstract\nI will start by giving a quic
k introduction to classical and symplectic Picard-Lefschetz theory. Then\,
I will explain the homological mirror symmetry (HMS) conjecture regarding
invertible polynomials. Finally\, I will sketch the A-side computation th
at goes into proving HMS in the chain type case. This is joint work with A
. Polishchuk.\n
LOCATION:https://stable.researchseminars.org/talk/UCGEN/7/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Kadri Ilker Berktav (Middle East Technical University)
DTSTART:20200930T150000Z
DTEND:20200930T163000Z
DTSTAMP:20260404T131145Z
UID:UCGEN/8
DESCRIPTION:Title: Higher Structures in Physics\nby Kadri Ilker Berktav (Middle East
Technical University) as part of UCGEN - Uluslararası Cebirsel GEometri
Neşesi\n\n\nAbstract\nThis is an overview of higher structures in physics
. In this talk\, we intend to outline the basics of derived algebraic geom
etry and its essential role in encoding the formal geometric aspects of mo
duli spaces of solutions to certain differential equations. Throughout the
talk\, we always study objects with higher structures in a functorial per
spective\, and we shall focus on algebraic local models for those structur
es. To be more precise\, we shall be interested in derived geometric const
ructions and higher spaces for certain moduli problems associated with cla
ssical field theories and their defining equations\, the so-called Euler-L
agrange equations. \nTo this end\, the talk is organized into two main par
ts: In the first part of the talk\, we shall revisit the naïve and algebr
o-geometric definition of a classical field theory together with some exam
ples\, and then we will establish the connection between classical field t
heories and moduli problems. In the second part of the talk\, we first rec
all the basic aspects of moduli theory in a categorical perspective and ex
plain how higher-categorical notions like stacks come into play to overcom
e certain technical problems naturally arising in many moduli problems. In
the spirit of these discussions\, we shall also give some examples from g
auge theory and Einstein gravity.\n
LOCATION:https://stable.researchseminars.org/talk/UCGEN/8/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Selvi Kara (University of South Alabama)
DTSTART:20201007T150000Z
DTEND:20201007T163000Z
DTSTAMP:20260404T131145Z
UID:UCGEN/9
DESCRIPTION:Title: Monomial Ideals of Graphs and Their Syzygies\nby Selvi Kara (Univ
ersity of South Alabama) as part of UCGEN - Uluslararası Cebirsel GEometr
i Neşesi\n\n\nAbstract\nGiven a homogeneous ideal $I$\n in a polynomial r
ing \n$R=k[x_1\,…\,x_n]$\,\n we can describe the structure of $I$\n by u
sing its minimal free resolution. All the information related to the minim
al free resolution of $I$\n is encoded in its Betti numbers. However\, it
is a difficult problem to express Betti numbers of any homogeneous ideal i
n a general way. Due to this difficulty\, it is common to focus on coarser
invariants of \n$I$ or particular classes of ideals. \n\nIn this talk\, w
e consider monomial ideals associated to graphs. We will discuss the Caste
lnuovo-Mumford regularity\, projective dimension\, and extremal Betti numb
ers of such ideals and provide formulas for these invariants in terms of t
he combinatorial data of their associated graphs. Results presented in thi
s talk are from joint works with Biermann\, O’Keefe\, Lin\, and Casiday.
\n
LOCATION:https://stable.researchseminars.org/talk/UCGEN/9/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Enis Kaya (University of Groningen)
DTSTART:20201014T150000Z
DTEND:20201014T163000Z
DTSTAMP:20260404T131145Z
UID:UCGEN/10
DESCRIPTION:Title: Explicit Vologodsky Integration for Hyperelliptic Curves\nby Eni
s Kaya (University of Groningen) as part of UCGEN - Uluslararası Cebirsel
GEometri Neşesi\n\n\nAbstract\nLet X be a curve over a p-adic field with
semi-stable reduction and let ω be a meromorphic 1-form on X. There are
two notions of p-adic integration one may associate to this data: the Berk
ovich–Coleman integral which can be performed locally\; and the Vologods
ky integral with desirable number-theoretic properties. In this talk\, we
present a theorem comparing the two\, and describe an algorithm for comput
ing Vologodsky integrals in the case that X is a hyperelliptic curve. We a
lso illustrate our algorithm with a numerical example computed in Sage. Th
is talk is partly based on joint work with Eric Katz.\n
LOCATION:https://stable.researchseminars.org/talk/UCGEN/10/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Irem Portakal (Otto von Guericke University Magdeburg)
DTSTART:20201021T150000Z
DTEND:20201021T163000Z
DTSTAMP:20260404T131145Z
UID:UCGEN/11
DESCRIPTION:Title: Rigid toric matrix Schubert varieties\nby Irem Portakal (Otto vo
n Guericke University Magdeburg) as part of UCGEN - Uluslararası Cebirsel
GEometri Neşesi\n\n\nAbstract\nIn this talk\, we introduce the usual tor
us action on matrix Schubert varieties. In the toric case we show that the
se varieties arise from a bipartite graph. We study the first order deform
ations of toric matrix Schubert varieties and we prove that it is rigid if
and only if the three-dimensional faces of its associated (edge) cone are
all simplicial.\n
LOCATION:https://stable.researchseminars.org/talk/UCGEN/11/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Özhan Genç (Jagiellonian University)
DTSTART:20201028T150000Z
DTEND:20201028T163000Z
DTSTAMP:20260404T131145Z
UID:UCGEN/12
DESCRIPTION:Title: Ulrich Trichotomy on del Pezzo Surfaces\nby Özhan Genç (Jagiel
lonian University) as part of UCGEN - Uluslararası Cebirsel GEometri Neş
esi\n\n\nAbstract\nA vector bundle $\\mathcal{E}$ on a projective variety
$X$ in $\\mathbb{P}^N$ is Ulrich if $\\rm{H}^∗(X\,E(−k))$ vanishes for
$1 ≤k ≤\\dim(X)$. It has been conjectured by Eisenbud and Schreyer th
at every projective variety carries an Ulrich bundle. Even though this con
jecture has not been proved or disproved\, another interesting question is
worth considering: classify projective varieties as Ulrich finite\, tame
or wild type with respect to families of Ulrich bundles that they support.
In this talk\, we will show that this trichotomy is exhaustive for certai
n del Pezzo surfaces with any given polarization. This talk is based on a
joint work with Emre Coşkun.\n
LOCATION:https://stable.researchseminars.org/talk/UCGEN/12/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Oğuz Şavk (Boğaziçi University)
DTSTART:20201104T150000Z
DTEND:20201104T163000Z
DTSTAMP:20260404T131145Z
UID:UCGEN/13
DESCRIPTION:Title: Brieskorn spheres\, homology cobordism and homology balls\nby O
ğuz Şavk (Boğaziçi University) as part of UCGEN - Uluslararası Cebirs
el GEometri Neşesi\n\n\nAbstract\nA classical question in low-dimensional
topology asks which \nhomology $3$-spheres bound homology $4$-balls. This
question is fairly \naddressed to Brieskorn spheres $\\Sigma(p\,q\,r)$. S
ince they are defined \nto be links of singularities $x^p+y^q+z^r=0$\, Bri
eskorn spheres are \nalgebro-geometric originated $3$-manifolds.\n\nOver t
he years\, Brieskorn spheres also have been the main objects for \nthe und
erstanding of the algebraic structure of the integral homology \ncobordism
group. In this talk\, we will present several families of \nBrieskorn sph
eres which do or do not bound integral and rational \nhomology balls. Also
\, we will investigate their positions in both \nintegral and rational hom
ology cobordism groups.\n
LOCATION:https://stable.researchseminars.org/talk/UCGEN/13/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Bahar Acu (Northwestern University)
DTSTART:20201111T150000Z
DTEND:20201111T163000Z
DTSTAMP:20260404T131145Z
UID:UCGEN/14
DESCRIPTION:Title: Understanding symplectic fillings of contact manifolds via algebraic
varieties\nby Bahar Acu (Northwestern University) as part of UCGEN -
Uluslararası Cebirsel GEometri Neşesi\n\n\nAbstract\nThis talk is an att
empt for a (pandemic-conscious) invitation to contact topology via an alg
ebro-geometric approach with the caveat that we admit having little to n
o understanding of many concepts in algebraic geometry. A very useful st
rategy in studying topological manifolds is to factor them into smaller
pieces. Briefly\, an "open book decomposition" on an $n$-dimensional m
anifold (the open book) is a type of fibration over a circle that helps
us study our manifold in terms of its $(n-1)$-dimensional fibers (the p
ages) and $(n-2)$-dimensional boundary of these fibers (the binding). Op
en books provide a natural framework for studying the topological propert
ies of a geometric phenomenon called "contact structures" on smooth ma
nifolds. In this talk\, we aim to provide an exposition of results\, some
of which are fruits of several joint works\, concerning "symplectic fil
lings" of contact manifolds given by certain classes of algebraic varie
ties using their "supporting" open books.\n
LOCATION:https://stable.researchseminars.org/talk/UCGEN/14/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Kadri İlker Berktav (Middle East Technical University)
DTSTART:20201125T150000Z
DTEND:20201125T160000Z
DTSTAMP:20260404T131145Z
UID:UCGEN/15
DESCRIPTION:Title: Higher Structures in Einstein Gravity\nby Kadri İlker Berktav (
Middle East Technical University) as part of UCGEN - Uluslararası Cebirse
l GEometri Neşesi\n\n\nAbstract\nThis is a talk on a recent investigation
about higher structures in the theory of General Relativity. It can be al
so seen as a direct sequel of the previous talk “Higher Structures in Ph
ysics.” However\, for the sake of completeness\, the talk will include a
brief summary of key ideas from the aforementioned talk. In that respect\
, we shall begin with revisiting the basics of moduli theory and derived a
lgebraic geometry. Next\, we will report some relevant constructions and r
esults from our work encoding various stacky formulations of Einstein Grav
ity.\n\nThis talk is a continuation of a previous talk of the speaker\, wh
ich you may find in the following link:\nhttps://www.youtube.com/watch?v=g
mUfTPcM7Go&t=2060s\n
LOCATION:https://stable.researchseminars.org/talk/UCGEN/15/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Ayşegül Öztürkalan (Abdullah Gül University)
DTSTART:20201118T150000Z
DTEND:20201118T160000Z
DTSTAMP:20260404T131145Z
UID:UCGEN/16
DESCRIPTION:Title: Loops in moduli spaces of real plane projective curves\nby Ayşe
gül Öztürkalan (Abdullah Gül University) as part of UCGEN - Uluslarara
sı Cebirsel GEometri Neşesi\n\n\nAbstract\nThe space of real algebraic p
lane projective curves of a fixed degree has a natural stratification. The
strata of top dimension consists of non-singular curves and are known up
to curves of degree 6. Topology and\, in particular\, fundamental groups o
f individual strata have not been studied systematically. We study the str
atum formed by non-singular sextics with the real part consisting of 9 ova
ls which lie outside each other and divide the set of complex points. Appa
rently this stratum has one of the most complicated fundamental groups. In
the talk I will study its subgroups which come from strata of singular cu
rves and originates from spaces of linear equivalent real divisors on a re
al cubic curve.\n
LOCATION:https://stable.researchseminars.org/talk/UCGEN/16/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Sema Güntürkün (University of Massachusetts Amherst)
DTSTART:20201202T150000Z
DTEND:20201202T160000Z
DTSTAMP:20260404T131145Z
UID:UCGEN/17
DESCRIPTION:Title: On the Eisenbud-Green-Harris conjecture.\nby Sema Güntürkün (
University of Massachusetts Amherst) as part of UCGEN - Uluslararası Cebi
rsel GEometri Neşesi\n\n\nAbstract\nA generalization of the Macaulay’s
theorem on the growth of Hilbert functions of homogeneous ideals in $K[x_1
\,\\ldots\, x_n]$ is conjectured by Eisenbud\, Green and Harris in the 90s
. The conjecture\, also known as the EGH conjecture\, states that the lex-
plus-powers ideals show an extremal behavior among the homogeneous ideals
containing regular sequences in terms of their Hilbert functions. In this
talk\, our focus will be on a case of the EGH conjecture for the homogene
ous ideals containing a regular sequence of quadratic forms. This is a joi
nt work with Mel Hochster.\n
LOCATION:https://stable.researchseminars.org/talk/UCGEN/17/
END:VEVENT
BEGIN:VEVENT
SUMMARY:İzzet Coşkun (University of Illinois at Chicago)
DTSTART:20201209T150000Z
DTEND:20201209T160000Z
DTSTAMP:20260404T131145Z
UID:UCGEN/18
DESCRIPTION:Title: Brill-Noether Theorems for moduli spaces of sheaves on surfaces\
nby İzzet Coşkun (University of Illinois at Chicago) as part of UCGEN -
Uluslararası Cebirsel GEometri Neşesi\n\n\nAbstract\nIn this talk\, I wi
ll describe several results on the cohomology of the general sheaf in a mo
duli space of sheaves on a projective surface. I will discuss joint work w
ith Jack Huizenga on rational surfaces such as Hirzebruch surfaces and joi
nt work with Howard Nuer and Kota Yoshioka on K3 surfaces.\n
LOCATION:https://stable.researchseminars.org/talk/UCGEN/18/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Burçin Güneş (Sabancı University)
DTSTART:20201216T150000Z
DTEND:20201216T160000Z
DTSTAMP:20260404T131145Z
UID:UCGEN/20
DESCRIPTION:Title: On nilpotent automorphism groups of function fields\nby Burçin
Güneş (Sabancı University) as part of UCGEN - Uluslararası Cebirsel GE
ometri Neşesi\n\n\nAbstract\nWe study the automorphisms of a function fie
ld of genus $g\\geq 2$ over an algebraically closed field of positive char
acteristic $p$. More precisely\, we show that the order of a nilpotent sub
group $G$ of its automorphism group is bounded by $16(g−1)$ when $G$ is
not a $p$-group. We show that if $|G|=16(g−1)$\, then $g−1$ is a power
of $2$. Furthermore\, we provide an infinite family of function fields at
taining the bound. This is a joint work with Nurdagül Anbar.\n
LOCATION:https://stable.researchseminars.org/talk/UCGEN/20/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Sümeyra Sakallı (University of Arkansas)
DTSTART:20210106T150000Z
DTEND:20210106T160000Z
DTSTAMP:20260404T131145Z
UID:UCGEN/21
DESCRIPTION:Title: Symplectic 4-Manifolds on the Noether Line and between the Noether a
nd Half Noether Lines\nby Sümeyra Sakallı (University of Arkansas) a
s part of UCGEN - Uluslararası Cebirsel GEometri Neşesi\n\n\nAbstract\nI
n this talk\, first we will review some main concepts and techniques in th
e smooth and symplectic 4-manifolds theory. Then we will discuss our const
ructions of exotic\, simply connected and symplectic 4-manifolds on the No
ether line and between the Noether and half Noether lines via pencils of c
omplex curves of genus one and via symplectic surgeries. We will also pres
ent a completely geometric way of constructing certain configurations of K
odaira’s singularities in the rational elliptic surfaces\, without using
any monodromy arguments.\n
LOCATION:https://stable.researchseminars.org/talk/UCGEN/21/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Levent Doğan (Technical University of Berlin)
DTSTART:20210113T150000Z
DTEND:20210113T160000Z
DTSTAMP:20260404T131145Z
UID:UCGEN/22
DESCRIPTION:Title: Polynomial Time Algorithms for Torus Actions\nby Levent Doğan (
Technical University of Berlin) as part of UCGEN - Uluslararası Cebirsel
GEometri Neşesi\n\n\nAbstract\nIn this talk\, we will consider three algo
rithmic problems\, namely orbit equivalence\, orbit closure intersection a
nd orbit containment problem for actions of tori. We will describe the rel
ated invariant theory and show that all three problems admit polynomial ti
me algorithms.\n
LOCATION:https://stable.researchseminars.org/talk/UCGEN/22/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Kürşat Sözer (University of Lille)
DTSTART:20210120T150000Z
DTEND:20210120T160000Z
DTSTAMP:20260404T131145Z
UID:UCGEN/23
DESCRIPTION:Title: Two-dimensional extended HQFTs with arbitrary targets\nby Kürş
at Sözer (University of Lille) as part of UCGEN - Uluslararası Cebirsel
GEometri Neşesi\n\n\nAbstract\nInspired by theoretical physics\, topologi
cal quantum field theories (TQFTs) produce manifold invariants behaving we
ll under gluing. Homotopy quantum field theories (HQFTs)\, introduced by T
uraev\, generalize TQFTs to manifolds equipped with continuous maps to fix
ed target space. A different generalization of TQFTs is given by extended
TQFTs which includes lower-dimensional manifolds utilizing higher categori
es. In this talk\, we define and classify 2-dimensional extended HQFTs wit
h arbitrary targets generalizing the earlier work on K(G\,1)-targets using
the methods introduced for TQFTs by Chris Schommer-Pries in 2009.\n
LOCATION:https://stable.researchseminars.org/talk/UCGEN/23/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Emre Şen (University of Iowa)
DTSTART:20210127T150000Z
DTEND:20210127T160000Z
DTSTAMP:20260404T131145Z
UID:UCGEN/24
DESCRIPTION:Title: Quivers in Algebraic Geometry: Various Examples\nby Emre Şen (U
niversity of Iowa) as part of UCGEN - Uluslararası Cebirsel GEometri Neş
esi\n\n\nAbstract\nThis will be an expository talk about quivers\, and the
ir representations. We will see why quivers naturally appear in the contex
t of algebraic geometry and how they are useful to solve algebrogeometric
problems. In this manner\, we discuss various subjects: group actions wit
h finitely many orbits\, derived categories of coherent sheaves\, toric ve
ctor bundles\, exceptional sequences\, quiver moduli etc.\n
LOCATION:https://stable.researchseminars.org/talk/UCGEN/24/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Oğuzhan Yürük (TU Braunschweig)
DTSTART:20210203T150000Z
DTEND:20210203T160000Z
DTSTAMP:20260404T131145Z
UID:UCGEN/25
DESCRIPTION:Title: Understanding the Regions of Multistaionarity via Symbolic Nonnegati
vity Certificates\nby Oğuzhan Yürük (TU Braunschweig) as part of UC
GEN - Uluslararası Cebirsel GEometri Neşesi\n\n\nAbstract\nParameterized
ordinary differential equation systems are crucial for modeling in bioche
mical reaction networks under the assumption of mass-action kinetics. Vari
ous questions concerning the signs of multivariate polynomials in positive
orthant arise from studying the solutions' qualitative behavior with resp
ect to parameter values. In this work\, we utilize circuit polynomials to
find symbolic certificates of nonnegativity in order to provide further in
sight into the number of positive steady states of the n-site phosphorylat
ion cycle model. This is a joint work with Elisenda Feliu\, Nidhi Kaihnsa
and Timo de Wolff.\n
LOCATION:https://stable.researchseminars.org/talk/UCGEN/25/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Özgür Esentepe (University of Connecticut)
DTSTART:20210210T150000Z
DTEND:20210210T160000Z
DTSTAMP:20260404T131145Z
UID:UCGEN/26
DESCRIPTION:Title: Annihilation of cohomology over curve singularities\nby Özgür
Esentepe (University of Connecticut) as part of UCGEN - Uluslararası Cebi
rsel GEometri Neşesi\n\n\nAbstract\nHilbert's syzygy theorem implies that
the second syzygy of every module over a polynomial ring S in two variabl
es is projective. In fancy language\, this means that $Ext_S^3(M\,N)$ vani
shes for every pair of modules $M\,N$. This is no longer true when we cons
ider a quotient $R$ of $S$ by an ideal generated by a single polynomial $f
$. In fact\, for every $i>0$ there is at least one pair $M\,N$ such that $
Ext_R^i(M\,N)\\neq 0$. We investigate the ideal consisting of ring element
s which uniformly annihilate all $Ext_R^i(M\,N)$ for sufficiently large $i
$. I am dedicating this talk to students and academics of Boğaziçi Unive
rsity who are protesting against a rector appointed by the 12th president
of Turkey and I will try my best to keep it accessible to a broad audience
.\n
LOCATION:https://stable.researchseminars.org/talk/UCGEN/26/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Sinem Odabaşı (Universidad Austral de Chile)
DTSTART:20210217T150000Z
DTEND:20210217T160000Z
DTSTAMP:20260404T131145Z
UID:UCGEN/27
DESCRIPTION:Title: On induced cotorsion pairs in functor category.\nby Sinem Odaba
şı (Universidad Austral de Chile) as part of UCGEN - Uluslararası Cebir
sel GEometri Neşesi\n\n\nAbstract\nThe question of interest that motivate
s our work is how to ensure that the category Add (A\,R-Mod) of additive f
unctors has a projective / injective model structure without putting any c
onditions on the ring R. Essentially\, it is motivated by the classical pr
ojective/injective/flat model structures on the category Ch(R) of chain co
mplexes of left R-modules.\n\n While we have been working on this problem
with my collegues\, in a recent work of Henrik Holm and Peter Jorgensen pu
blished in arXiv arXiv:2101.06176\, this problem is handled by using techn
iques/results in Gorenstein Homological Algebra. \n\nFortunately\, our app
roach differs from theirs\, and includes other contexts such as module cat
egory over a formal triangular matrix ring.\n\nWith this objective in mind
\, in this talk we will talk about how to build "possible" Hovey cotorsion
pairs^1 in Add (A\, R-Mod)\, and later we will present an explicit charac
terization of their objects. The results obtained on these cotorsion pairs
in Add (A\, R-Mod) generalize the known results in the categories of chai
n complexes of R-modules and modules over a formal triangular matrix ring.
It is a work in progress with Sergio Estrada and Manuel Cortes Izurdiaga.
\n\n1: There is a close relation between abelian model structures in abeli
an categories and Hovey pairs\; see [Hov02]. That's why we focus on findin
g suitable Hovey pairs in Add (A\, R-Mod).\n\n[Hov02] Hovey\, M. Cotorsion
pairs\, model category structures\, and representation theory. Math Z 241
\, 553–592 (2002).\n
LOCATION:https://stable.researchseminars.org/talk/UCGEN/27/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Büşra Sert (TU Dresden)
DTSTART:20210224T150000Z
DTEND:20210224T160000Z
DTSTAMP:20260404T131145Z
UID:UCGEN/28
DESCRIPTION:Title: Combinatorial Methods for Minkowski Tensors of Polytopes\nby Bü
şra Sert (TU Dresden) as part of UCGEN - Uluslararası Cebirsel GEometri
Neşesi\n\n\nAbstract\nIntrinsic volumes of a convex body provide scalar d
ata (volume\, surface area\, Euler characteristic etc. ) about the geometr
y of a convex body intrinsically\, i.e.\, the data doesn't depend on the a
mbient space. Minkowski tensors are the tensor valued generalization of in
trinsic volumes. They give not only scalar data on the geometry of a conve
x body\, but also information about its shape\, orientation etc..\nMoreove
r\, generating functions for moments of the uniform distribution on convex
bodies provide us a way to extract entries of Minkowski volume tensors.\
n\nIn this talk\, we first give necessary background on Minkowski tensors
and their connection to moments on polytopes. Then\, we describe Minkowski
"surface tensors"\, and focus on some methods to obtain their entries in
the case of simplicial polytopes.\n\nThis is a joint work with Niklas Liv
chitz and Amy Wiebe.\n
LOCATION:https://stable.researchseminars.org/talk/UCGEN/28/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Emrah Sercan Yılmaz (Boğaziçi University)
DTSTART:20210303T160000Z
DTEND:20210303T173000Z
DTSTAMP:20260404T131145Z
UID:UCGEN/29
DESCRIPTION:by Emrah Sercan Yılmaz (Boğaziçi University) as part of UCG
EN - Uluslararası Cebirsel GEometri Neşesi\n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/UCGEN/29/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Matthew Habermann (London School of Geometry and Number Theory)
DTSTART:20210324T160000Z
DTEND:20210324T173000Z
DTSTAMP:20260404T131145Z
UID:UCGEN/30
DESCRIPTION:Title: Homological mirror symmetry for nodal stacky curves\nby Matthew
Habermann (London School of Geometry and Number Theory) as part of UCGEN -
Uluslararası Cebirsel GEometri Neşesi\n\n\nAbstract\nIn this talk I wil
l explain the proof of homological mirror symmetry where the B-side is a r
ing or chain of stacky projective lines joined nodally\, and where each ir
reducible component is allowed to have a non-trivial generic stabiliser\,
generalising the work of Lekili and Polishchuk. The key ingredient of the
proof is to match categorical resolutions on the A- and B-sides by identif
ying them both with an intermediary category given by the derived category
of modules of a gentle algebra. I will explain the strategy of constructi
ng these resolutions on the A-- and B--sides\, as well as how to deduce ho
mological mirror symmetry from this.\n
LOCATION:https://stable.researchseminars.org/talk/UCGEN/30/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Nursel Erey
DTSTART:20210331T160000Z
DTEND:20210331T173000Z
DTSTAMP:20260404T131145Z
UID:UCGEN/31
DESCRIPTION:Title: Edge ideals and some numerical invariants of graded resolutions\
nby Nursel Erey as part of UCGEN - Uluslararası Cebirsel GEometri Neşesi
\n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/UCGEN/31/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Olgür Çelikbaş (West Virginia University)
DTSTART:20210407T150000Z
DTEND:20210407T160000Z
DTSTAMP:20260404T131145Z
UID:UCGEN/32
DESCRIPTION:Title: On torsion in tensor products of modules\nby Olgür Çelikbaş (
West Virginia University) as part of UCGEN - Uluslararası Cebirsel GEomet
ri Neşesi\n\n\nAbstract\nTensor products are fundamental objects used in
many areas including mathematics\, physics\, and engineering.\nIn 1961 Mau
rice Auslander initiated the study of torsion in tensor products of finite
ly generated modules in his pioneering paper\, \nModules over unramified r
egular local rings (Illinois J. Math. 5\, 1961\, 631-647). Subsequently\,
in 1994\, Craig Huneke and Roger Wiegand \nextended and studied Auslander
’s results over hypersurface rings in their influential paper\, Tensor p
roducts of modules and the rigidity of Tor \n(Math. Ann. 299\, 1994\, no.
3\, 449–476).\n\nIn this talk I will discuss some of the results of Ausl
ander\, and Huneke and Wiegand\, concerning the existence of torsion in te
nsor products\nof finitely generated modules over commutative Noetherian l
ocal rings. I also plan to talk about my work on the reflexivity of tensor
products\, \nwhich was motivated by the second rigidity theorem of Huneke
and Wiegand.\n
LOCATION:https://stable.researchseminars.org/talk/UCGEN/32/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Sergio Estrada (University of Murcia)
DTSTART:20210414T150000Z
DTEND:20210414T160000Z
DTSTAMP:20260404T131145Z
UID:UCGEN/33
DESCRIPTION:Title: The big singularity category of a non-affine scheme\nby Sergio E
strada (University of Murcia) as part of UCGEN - Uluslararası Cebirsel GE
ometri Neşesi\n\n\nAbstract\nA classic result of Buchweitz shows that the
singularity category of a Gorenstein local ring A is triangulated equival
ent to the stable category of finitely generated Gorenstein projective A-m
odules and to the homotopy category of totally acyclic complexes of finite
ly generated projective A-modules. In this talk we present a non-affine ve
rsion of this result. To achieve this we will define a "big" version of Or
lov´s singularity category.The talk is based on a project developed with
Lars Christensen (Texas Tech University) and Peder Thompson (Norwegian Uni
versity of Science and Technology).\n
LOCATION:https://stable.researchseminars.org/talk/UCGEN/33/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Tim Tribone
DTSTART:20210421T150000Z
DTEND:20210421T160000Z
DTSTAMP:20260404T131145Z
UID:UCGEN/34
DESCRIPTION:Title: Matrix factorizations with more than two factors\nby Tim Tribone
as part of UCGEN - Uluslararası Cebirsel GEometri Neşesi\n\n\nAbstract\
nGiven an element f in a regular local ring\, a matrix factorization of f
is a pair of square matrices such that their product is $f$ times an ident
ity matrix of the appropriate size. These objects were originally introduc
ed by Eisenbud to study the hypersurface ring defined by f. We will discus
s some of the basic theory of matrix factorizations and then specialize to
a generalization where the factorizations have more than two factors.\n
LOCATION:https://stable.researchseminars.org/talk/UCGEN/34/
END:VEVENT
END:VCALENDAR