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BEGIN:VEVENT
SUMMARY:Oğuz Şavk (Boğaziçi Üniversitesi)
DTSTART:20211105T140000Z
DTEND:20211105T150000Z
DTSTAMP:20260404T110910Z
UID:MSGSUMath/1
DESCRIPTION:Title: Classical and new plumbings bounding contractible manifolds and
homology balls\nby Oğuz Şavk (Boğaziçi Üniversitesi) as part of M
imar Sinan University Mathematics Seminars\n\n\nAbstract\nA central proble
m in low-dimensional topology asks which \nhomology 3-spheres bound contra
ctible 4-manifolds and homology 4-balls. \nIn this talk\, we address this
problem for plumbed 3-manifolds and we \npresent the classical and new res
ults together. Our approach is based on \nMazur’s famous argument and it
s generalization which provides a \nunification of all results.\n
LOCATION:https://stable.researchseminars.org/talk/MSGSUMath/1/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Can Ozan Oğuz (Galatasaray Üniversitesi)
DTSTART:20211112T140000Z
DTEND:20211112T150000Z
DTSTAMP:20260404T110910Z
UID:MSGSUMath/2
DESCRIPTION:Title: Tekrarlı Çelenk Çarpımlarında Kısıtlama ve Yükseltme\
nby Can Ozan Oğuz (Galatasaray Üniversitesi) as part of Mimar Sinan Univ
ersity Mathematics Seminars\n\n\nAbstract\nSimetrik grubun temsilleri pek
çok sebepten dolayı ilgi görüyor. 2010 yılında Khovanov\, bu temsill
er üzerindeki kısıtlama ve yükseltme operatörlerinin ilişkilerinden
oluşan bir kategori tanımladı: Heisenberg kategorisi. Devamında bu ça
lışma simetrik grubun Frobenius cebirleri ile çelenk çarpımlarına ge
nelleştirildi. Biz konuyu farklı bir yönde\, simetrik grupların birbir
leri ile tekrarlı çelenk çarpımları için ele alıyoruz. Bu durumda k
ısıtlama ve yükseltme operatörleri arasındaki ilişkileri tarif eden
bir kategorinin yapısını kısmi olarak ortaya koyuyoruz. Mee Seong Im i
le ortak çalışmamızdır.\n
LOCATION:https://stable.researchseminars.org/talk/MSGSUMath/2/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Berrin Şentürk (TED Üniversitesi)
DTSTART:20211126T140000Z
DTEND:20211126T150000Z
DTSTAMP:20260404T110910Z
UID:MSGSUMath/3
DESCRIPTION:Title: Free group actions on products of spheres\nby Berrin Şentür
k (TED Üniversitesi) as part of Mimar Sinan University Mathematics Semina
rs\n\n\nAbstract\nOne of the engaging problems in the field of algebraic t
opology is the \nclassification of group actions on manifolds. In this tal
k\, we consider \nfree finite group actions on a product of spheres. We wi
ll discuss the \nupper bound for the rank of the group that can act freely
on this \nproduct by using algebraic methods.\n
LOCATION:https://stable.researchseminars.org/talk/MSGSUMath/3/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Cihan Okay (Bilkent Üniversitesi)
DTSTART:20220107T140000Z
DTEND:20220107T150000Z
DTSTAMP:20260404T110910Z
UID:MSGSUMath/4
DESCRIPTION:Title: Homotopy classification of operator solutions of linear systems\nby Cihan Okay (Bilkent Üniversitesi) as part of Mimar Sinan Universit
y Mathematics Seminars\n\n\nAbstract\nLinear systems of equations over a f
inite field play an important role in quantum information theory. Instead
of looking for solutions over the base field one can look for solutions (i
n a certain sense) over the unitary group\, which are called operator solu
tions. The data of this system of equations can be expressed using a hyper
graph and the operator solutions can be studied from a topological point o
f view by considering certain topological realizations of these hypergraph
s. In this talk I will describe how homotopical methods provide a way to c
lassify operator solutions of linear systems. Our basic approach is to int
erpret operator solutions as maps from a topological realization of the hy
pergraph to a certain classifying space first introduced by Adem-Cohen-Tor
res Giese.\n
LOCATION:https://stable.researchseminars.org/talk/MSGSUMath/4/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Şeyda İpek (Carleton University)
DTSTART:20211119T140000Z
DTEND:20211119T150000Z
DTSTAMP:20260404T110910Z
UID:MSGSUMath/5
DESCRIPTION:Title: Fundamental symmetries of nature\nby Şeyda İpek (Carleton U
niversity) as part of Mimar Sinan University Mathematics Seminars\n\n\nAbs
tract\nThe building blocks of our universe\, elementary particles\, obey s
ome simple rules based on certain symmetry arguments. The most basic inter
actions of elementary particles can be described by the Standard Model\, w
hose underlying symmetry structure is described by the group structure SU(
3)xSU(2)xU(1). There are more symmetries--sometimes empirical\, sometimes
accidental--we encounter when studying elementary particles. Some of these
symmetries must be broken in order for our universe to work\, e.g. based
on our observations matter--antimatter symmetry is not a good symmetry sin
ce we do not have any antimatter in the universe while the SM has this sym
metry. I will give a broad overview of the interconnection between partic
le physics and symmetries and how they help us build theoretical models of
our universe.\n
LOCATION:https://stable.researchseminars.org/talk/MSGSUMath/5/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Özgür Martin (MSGSÜ)
DTSTART:20211203T140000Z
DTEND:20211203T150000Z
DTSTAMP:20260404T110910Z
UID:MSGSUMath/6
DESCRIPTION:Title: Bolstering Stochastic Gradient Descent with Model Building\nb
y Özgür Martin (MSGSÜ) as part of Mimar Sinan University Mathematics Se
minars\n\n\nAbstract\nStochastic gradient descent method and its variants
constitute the core optimization algorithms that achieve good convergence
rates for solving machine learning problems. These rates are obtained espe
cially when these algorithms are fine-tuned for the application at hand. A
lthough this tuning process can require large computational costs\, recent
work has shown that these costs can be reduced by line search methods tha
t iteratively adjust the stepsize. In this talk\, we will introduce an alt
ernative approach to stochastic line search by using a new algorithm based
on forward step model building. This model building step incorporates a s
econd-order information that allows adjusting not only the stepsize but al
so the search direction.\n\nThis is a joint work with S. I. Birbil\, G. On
ay\, and F. Öztoprak.\n
LOCATION:https://stable.researchseminars.org/talk/MSGSUMath/6/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Esma Dirican Erdal (Yeditepe Üniversitesi)
DTSTART:20220114T140000Z
DTEND:20220114T150000Z
DTSTAMP:20260404T110910Z
UID:MSGSUMath/7
DESCRIPTION:Title: Multiplicative Gluing Formulas for the R-torsion of (n-2)-Connect
ed Closed pi-Manifolds\nby Esma Dirican Erdal (Yeditepe Üniversitesi)
as part of Mimar Sinan University Mathematics Seminars\n\n\nAbstract\nLet
$M$ be a closed orientable $(n-2)$-connected $2n$-dimensional $\\pi$-mani
fold. Such a manifold $M$ can be decomposed as a connected sum of certain
simpler manifolds. In this talk\, by using such connected sum decompositio
ns\, we will give multiplicative gluing formulas that express the Reidemei
ster torsion of $M$ with untwisted $\\mathbb{R}$-coefficients in terms of
Reidemeister torsions of its building blocks. This is a joint work with Ya
şar Sözen.\n
LOCATION:https://stable.researchseminars.org/talk/MSGSUMath/7/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Asgar Jamneshan (Koç Üniversitesi)
DTSTART:20211217T140000Z
DTEND:20211217T150000Z
DTSTAMP:20260404T110910Z
UID:MSGSUMath/8
DESCRIPTION:Title: The structure of arbitrary Conze-Lesigne systems\nby Asgar Ja
mneshan (Koç Üniversitesi) as part of Mimar Sinan University Mathematics
Seminars\n\n\nAbstract\nWe consider probability-preserving dynamical syst
ems from countable abelian group actions. Such a system is said to be a C
onze-Lesigne system if it is equal to its second Host-Kra-Ziegler factor (
these factors arise in the study of multiple recurrence and play a foundat
ional role in related areas in additive combinatorics and number theory).
We provide a classification of Conze-Lesigne systems in terms of algebrai
c data. More precisely\, we show that an arbitrary Conze-Lesigne system i
s an inverse limit of translational systems arising from locally compact n
ilpotent groups of nilpotency class 2 quotient by a lattice. Results of t
his type were previously known when the acting group is finitely generated
or a direct sum of cyclic groups. The talk aims at introducing the field
. If time permits\, we will present an application to additive combinator
ics. The talk is based on recent joint works with Or Shalom and Terence T
ao.\n
LOCATION:https://stable.researchseminars.org/talk/MSGSUMath/8/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Shigeo Koshitani (Chiba University)
DTSTART:20220121T140000Z
DTEND:20220121T150000Z
DTSTAMP:20260404T110910Z
UID:MSGSUMath/9
DESCRIPTION:Title: What has happened\, is happening and is going to happen in repres
entation theory of finite groups\nby Shigeo Koshitani (Chiba Universit
y) as part of Mimar Sinan University Mathematics Seminars\n\n\nAbstract\nW
e are going to talk on representation theory of finite groups\,\nespeciall
y on modular representation theory due to Richard Brauer\n(1901--1977) in
the last several decades. More precisely by starting off\nkind of history
of representation theory and then hopefully we would like to\nreach to rec
ent big results on some of the local-global conjectures\noriginally due to
Brauer. This is sort of general talk\, so almost no\nadvanced knowledge s
hould be needed except the definitions of groups\,\nrings\, fields\, and m
atrices.\n
LOCATION:https://stable.researchseminars.org/talk/MSGSUMath/9/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Aslıhan Ünsal (Sabancı Üniversitesi)
DTSTART:20211210T140000Z
DTEND:20211210T150000Z
DTSTAMP:20260404T110910Z
UID:MSGSUMath/10
DESCRIPTION:Title: Innovative Approaches in STEM* Education\nby Aslıhan Ünsal
(Sabancı Üniversitesi) as part of Mimar Sinan University Mathematics Se
minars\n\n\nAbstract\nIn a rapidly changing world\, we need to consider th
e following two points while planning higher education\; change in student
profiles and their learning needs\; demand for collaborative efforts of e
xperts to tackle world-wide problems\, such as global warming. In 2013\, a
t Sabanci University\, we started to redesign our freshman science course
to better prepare our students for their careers after graduation accordi
ng to global needs. In this talk\, I will be sharing the design and the im
plementation process of our integrated science course. \n\n*: Science\, Te
chnology\, Engineering\, Mathematics.\n\nKeywords: Active learning\; Peer
support\; Backward course design\n
LOCATION:https://stable.researchseminars.org/talk/MSGSUMath/10/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Serdar Ay (Atılım Üniversitesi)
DTSTART:20211224T130000Z
DTEND:20211224T140000Z
DTSTAMP:20260404T110910Z
UID:MSGSUMath/11
DESCRIPTION:Title: Adjointable Operators of Barreled VH-Spaces is a Locally $C^*$-
Algebra\nby Serdar Ay (Atılım Üniversitesi) as part of Mimar Sinan
University Mathematics Seminars\n\n\nAbstract\nA VH-space (Vector Hilbert
Space in the sense of Loynes) is a complex complete locally convex space w
ith a suitable ordered vector space valued inner product. Examples of VH-s
paces include\, but is not limited to\, the chain of locally Hilbert $C^*$
-modules\, Hilbert $C^*$-modules and Hilbert Spaces\n We prove that\, o
n a Barreled VH-Space\, the set of all adjointable operators consists of b
ounded operators and is a Locally $C^*$-Algebra\, generalizing the well kn
own corresponding fact from the theory of Locally Hilbert $C^*$-modules. \
n\n We pick a consequence of this result in the dilation theory of VH-S
paces and show that\, under the barreledness assumption\, a necessary and
sufficient condition for the existence of VH-space linearisations\, equiva
lently\, of reproducing kernel VH-Spaces\, is satisfied automatically.\n\n
The talk is not at our usual time\, it will be at 16.00\n
LOCATION:https://stable.researchseminars.org/talk/MSGSUMath/11/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Constantin-Cosmin Todea (Technical University of Cluj-Napoca)
DTSTART:20220330T120000Z
DTEND:20220330T130000Z
DTSTAMP:20260404T110910Z
UID:MSGSUMath/12
DESCRIPTION:Title: Nontriviality of the first Hochschild cohomology of some block a
lgebras of finite groups\nby Constantin-Cosmin Todea (Technical Unive
rsity of Cluj-Napoca) as part of Mimar Sinan University Mathematics Semina
rs\n\n\nAbstract\nHochschild cohomology $\\mathrm{HH}^*(A)$ of an associat
ive (unital) $k$-algebra $A$ (here $k$ is a field) has a rich structure. F
irst Hochschild\ncohomology $\\mathrm{HH}^1(A)$ is isomorphic to the quoti
ent of the space of $k$-linear derivations\nof $A$ modulo its inner deriva
tions. In the context of modular representation theory\, if the field $k$
has characteristic $p$ and $G$ is a finite group\, an indecomposable direc
t algebra factor $B$ of the group algebra $kG$ is called block algebra. I
s $\\mathrm{HH}^1(B)$ nontrivial for any block algebra $B$ with nontrivia
l defect group? This is a question launched by Markus Linckelmann at the I
CRA 2016. We explain the basic facts needed to understand this question.
We give methods to investigate the nontriviality of the first Hochschild
cohomology of some twisted group algebras. As a consequence we show that f
or some block algebras\, with nontrivial defect groups\, the first Hochsch
ild cohomology is nontrivial.\n
LOCATION:https://stable.researchseminars.org/talk/MSGSUMath/12/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Mehmet Akif Erdal (Yeditepe University)
DTSTART:20220406T120000Z
DTEND:20220406T130000Z
DTSTAMP:20260404T110910Z
UID:MSGSUMath/13
DESCRIPTION:Title: An Elmendorf-Piacenza style Theorem for actions of monoids\n
by Mehmet Akif Erdal (Yeditepe University) as part of Mimar Sinan Universi
ty Mathematics Seminars\n\n\nAbstract\nIn this talk I will describe a homo
topy theory for actions of monoids that is built by analyzing their ``reve
rsible parts". Let $M$ be a monoid. For each submonoid $N\\leq M$ let $G(N
)$ be the group completion of $N$. Given an $M$-space $X$ and a submonoid
$N\\leq M$\, we associate a $G(N)$-space $q_*^N(X)$ which sorts out “sym
metries” of the $N$-space $X$ with the restricted $N$-action. By using t
hese $q_*^N$'s we induce a model structure on the category of $M$-spaces a
nd $M$-equivariant and show that this model structure is Quillen equivalen
t to the projective model structure on the category of contravariant $\\ma
thbf{O}(M)$-diagrams of spaces\, where $\\mathbf{O}(M)$ is the category wh
ose objects are induced orbits $M\\times_N G(N)/H$ for each $N\\leq M$ and
$H\\leq G(N)$ and morphisms are $M$-equivariant maps. Finally\, if time p
ermits\, I will state some applications.\n
LOCATION:https://stable.researchseminars.org/talk/MSGSUMath/13/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Nadia Romero (Universidad de Guanajuato)
DTSTART:20220427T130000Z
DTEND:20220427T140000Z
DTSTAMP:20260404T110910Z
UID:MSGSUMath/14
DESCRIPTION:Title: Green fields\nby Nadia Romero (Universidad de Guanajuato) as
part of Mimar Sinan University Mathematics Seminars\n\n\nAbstract\nGreen
fields were discovered by Serge Bouc in 2019. To be precise\, the terminol
ogy was introduced at the very end of his paper Relative B-groups\, publis
hed in 2019. A Green field is a commutative Green biset functor with no no
n-trivial ideals. In this talk I will present some properties of a Green f
ield and examples of known Green biset functors which are Green fields. Th
is is a joint work with Serge Bouc.\n
LOCATION:https://stable.researchseminars.org/talk/MSGSUMath/14/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Şükran Gül Erdem (TED University)
DTSTART:20220617T100000Z
DTEND:20220617T110000Z
DTSTAMP:20260404T110910Z
UID:MSGSUMath/15
DESCRIPTION:Title: Beauville p-groups\nby Şükran Gül Erdem (TED University)
as part of Mimar Sinan University Mathematics Seminars\n\n\nAbstract\nBeau
ville surfaces are a class of rigid complex surfaces that have many nice g
eometric properties. \n A finite group giving rise to such a surface is
called a \\textit {Beauville group}.\n What makes them so good to deal w
ith is the fact that they can be described in purely group theoretical ter
ms.\n A finite group $G$ is a Beauville group if $G$ is a $2$-generator
group and it has a pair of generating sets $\\{x_1\, y_1\\}$ and $\\{x_2\,
y_2\\}$ such that\n $\\Sigma (x_1\,y_1) \\cap \\Sigma(x_2\,y_1)=\\{1\\}$
where for $i=1\, 2$\n \\[\n \\Sigma(x_i\,y_i)\n =\n \\bigcup_{g\\
in G} \\\,\n \\Big( \\langle x_i \\rangle^g \\cup \\langle y_i \\rangle^
g \\cup \\langle x_iy_i \\rangle^g \\Big).\n \\]\n \n Catanese showe
d in 2000 that the abelian Beauville groups are those of the form $C_n \\t
imes C_n$ with $(n\,6)=1$. \n After abelian groups\, the most natural cl
ass of finite groups to consider are nilpotent groups. \n One can easily
show that the study of nilpotent Beauville groups can be reduced to that
of Beauville $p$-groups.\n \n In this talk we survey a large collectio
n of results on Beauville $p$-groups: from the earliest examples of Beauvi
lle $p$-groups to Beauville $p$-groups in the most known families of $p$-g
roups with a good behavior with respect to powers\, such as regular $p$-gr
oups\, powerful $p$-groups\, $p$-central $p$-groups etc.\n \n We furth
er focus on infinite families of Beauville $p$-groups arising from the quo
tients of infinite groups such as the free group\, free product and triang
le groups.\n
LOCATION:https://stable.researchseminars.org/talk/MSGSUMath/15/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Taro Sakurai (Chiba University)
DTSTART:20220323T120000Z
DTEND:20220323T130000Z
DTSTAMP:20260404T110910Z
UID:MSGSUMath/16
DESCRIPTION:Title: The isomorphism problem for modular group algebras\nby Taro
Sakurai (Chiba University) as part of Mimar Sinan University Mathematics S
eminars\n\n\nAbstract\nSuppose that two finite p-groups G and H have isomo
rphic group algebras\nover the field with p elements. Are G and H isomorph
ic? This is a simple\nproblem which is known for more than half a century\
, and it is known to be\nnotoriously hard. Recently this problem has been
drawn attention again and\nstriking progress was made. I will present a sh
ort history of the problem\,\nexplain some primary techniques\, and touch
upon my latest work with Leo\nMargolis and Mima Stanojkovski.\n
LOCATION:https://stable.researchseminars.org/talk/MSGSUMath/16/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Neslihan Girgin (MSGSU)
DTSTART:20220525T120000Z
DTEND:20220525T130000Z
DTSTAMP:20260404T110910Z
UID:MSGSUMath/17
DESCRIPTION:Title: A Number Theoretical Approach to the Polynomials over Finite Fie
lds\nby Neslihan Girgin (MSGSU) as part of Mimar Sinan University Math
ematics Seminars\n\n\nAbstract\nLet q be a prime power and Fq be the finit
e field with q elements. The explicit constructions\nof irreducible polyno
mials over Fq is one of the main problems in the arithmetic of\nfinite fie
lds which has many applications in several areas such as coding theory\, c
ryptography\,\netc. In general\, some recursive methods are preferred to d
o these constructions using\nrational transformations. \nIn particular\, w
e are interested in methods that are obtained by using\nquadratic transfor
mations. For doing this\, we will first classify and normalize the rationa
l transformations of degree 2 using the behaviour of the ramified places i
n the corresponding rational function field extensions over the finite fie
ld Fq. Then we will investigate the constructions using Galois theory and
some basic observations in group theory. This approach provides to underst
and the iterative constructions better and gives various generalisations o
f them. It also helps to determine the requirements put on the initial pol
ynomials easier.\n
LOCATION:https://stable.researchseminars.org/talk/MSGSUMath/17/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Semra Öztürk (METU)
DTSTART:20220608T120000Z
DTEND:20220608T130000Z
DTSTAMP:20260404T110910Z
UID:MSGSUMath/19
DESCRIPTION:Title: On m-th roots of nilpotent matrices\nby Semra Öztürk (METU
) as part of Mimar Sinan University Mathematics Seminars\n\n\nAbstract\nTh
is talk is based on the paper with the same title which appeared in Electr
onic Journal of Linear Algebra\, November 2021 it is dedicated to the memo
ry of dear Professor Cem Tezer.\n\nA new necessary and sufficient conditio
n for the existence of an m-th root\nof a nilpotent matrix in terms of the
multiplicities of Jordan blocks is obtained\nand expressed as a system of
linear equations with nonnegative integer entries.\nThus\, computation of
the Jordan form of the m-th power of a nilpotent matrix\nis reduced to a
single matrix multiplication\; conversely\, the existence of an m-th\nroot
of a nilpotent matrix is reduced to the existence of a nonnegative intege
r\nsolution to the corresponding system of linear equations. For a singula
r matrix\nhaving an m-th root with a pair of nilpotent Jordan blocks of si
zes s and l\,\na new m-th root is constructed by replacing that pair by an
other one of sizes\ns + i and l − i\, for special s\, l\, i. If time per
mits we can state some results for\nthe existence of m-th roots of A^k for
a matrix A over an arbitrary field that is\na sum of two commuting matric
es where k ≥ t and t is the nilpotency of the\nnilpotent part of A.\n
LOCATION:https://stable.researchseminars.org/talk/MSGSUMath/19/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Haldun Özgür Bayındır (City\, University of London)
DTSTART:20220413T120000Z
DTEND:20220413T130000Z
DTSTAMP:20260404T110910Z
UID:MSGSUMath/20
DESCRIPTION:Title: Adjoining roots to ring spectra and algebraic K-theory\nby H
aldun Özgür Bayındır (City\, University of London) as part of Mimar Si
nan University Mathematics Seminars\n\n\nAbstract\nThe category of spectra
captures an important part of the complexity of topological spaces while
providing generalizations of many important notions in homological algebra
. \n\nIn this work\, we develop a new method to adjoin roots to ring spect
ra and show that this process results in interesting splittings in algebra
ic K-theory.\n\nIn the first part of my talk\, I will provide motivation f
or algebraic K-theory and highly structured ring spectra. After this\, I w
ill discuss trace methods\, a program that provides computational tools fo
r algebraic K-theory\, and introduce our results.\n\nThis is a joint work
in progress with Tasos Moulinos and Christian Ausoni.\n
LOCATION:https://stable.researchseminars.org/talk/MSGSUMath/20/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Daniel Max Hoffmann (University of Warsaw)
DTSTART:20220420T120000Z
DTEND:20220420T130000Z
DTSTAMP:20260404T110910Z
UID:MSGSUMath/21
DESCRIPTION:Title: On finite group action and model theory\nby Daniel Max Hoffm
ann (University of Warsaw) as part of Mimar Sinan University Mathematics S
eminars\n\n\nAbstract\nI will present results from my joint project with P
iotr Kowalski. It is about a model-theoretic description of actions of a f
ixed finite group on quite arbitrary structures. More precisely\, take a b
ig model M of some stable theory and a group G. Consider the family of all
substructures of M equipped with a group action (by automorphisms) of G.
The question is whether the sub-family of existentially closed (i.e. rich
in "solutions of equations") substructures with a group action of G can b
e axiomatized\, so whether we can first order statements which correspond
to being rich in solutions. We will analyze the situation for finite G and
express the problem in terms involving only the invariants of the group a
ction.\n
LOCATION:https://stable.researchseminars.org/talk/MSGSUMath/21/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Rizos Sklinos (Chinese Academy of Sciences)
DTSTART:20220511T120000Z
DTEND:20220511T130000Z
DTSTAMP:20260404T110910Z
UID:MSGSUMath/22
DESCRIPTION:Title: Elementary theories of hyperbolic groups\nby Rizos Sklinos (
Chinese Academy of Sciences) as part of Mimar Sinan University Mathematics
Seminars\n\n\nAbstract\nThe discovery of non euclidean geometry in the ea
rly nineteenth century had shaken the beliefs and conjectures of more than
two thousand years and changed the picture we had for mathematics\, physi
cs and even philosophy. Lobachevsky and Bolyai independently around 1830 d
iscovered hyperbolic geometry. A notable distinguish feature of hyperbolic
geometry is its negative curvature in a way that the sum of angles of a t
riangle is less than π. Gromov much later in 1987 introduced hyperbolic g
roups which are groups acting “nicely” on hyperbolic spaces\, or equiv
alently finitely generated groups whose Cayley graphs are “negatively cu
rved”. Main examples are free groups and almost all surface groups. The
fascinating subject of hyperbolic groups touches on many mathematical disc
iplines such as geometric group theory\, low dimensional topology and comb
inatorial group theory. It is connected to model theory through a question
of Tarski.\n\nTarski asked around 1946 whether non abelian free groups ha
ve the same first order theory. This question proved extremely hard to ans
wer and only after more than fifty years in 2001 Sela and Kharlampovich-My
asnikov answered it positively. Both works are voluminous and have not bee
n fully absorbed yet. The great novelty of the methods and the depth of th
e needed results have made it hard to streamline any of the proofs. Despit
e the difficulties there is some considerable progress in the understandin
g of the first-order theory of “the free group” and consequently first
-order theories of hyperbolic groups from the scopes of basic model theory
\, Shelah’s classification theory and geometric stability. In this talk
I will survey what is known about these theories and what are the main ope
n questions.\n
LOCATION:https://stable.researchseminars.org/talk/MSGSUMath/22/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Aslı Güçlükan İlhan (Dokuz Eylül University)
DTSTART:20220518T120000Z
DTEND:20220518T130000Z
DTSTAMP:20260404T110910Z
UID:MSGSUMath/23
DESCRIPTION:Title: Weakly equivariant classification of small covers over a product
of simplices\nby Aslı Güçlükan İlhan (Dokuz Eylül University) a
s part of Mimar Sinan University Mathematics Seminars\n\n\nAbstract\nA sma
ll cover over an n-dimensional simple convex polytope P is a smooth closed
manifold with a locally standard $\\mathbb{Z}_2^n$-action whose orbit spa
ce can be identified with P. Small covers over P can be classified using c
haracteristic functions from the set of facets of P to $\\mathbb{Z}_2^n$.
In this talk\, we give a weakly $\\mathbb{Z}_2^n$-equivariant classificati
on of small covers over a product of simplices in terms of associated digr
aphs. This is a joint work with S. Kaan Gürbüzer.\n
LOCATION:https://stable.researchseminars.org/talk/MSGSUMath/23/
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BEGIN:VEVENT
SUMMARY:Özge Ülkem (Galatasaray University)
DTSTART:20220601T120000Z
DTEND:20220601T130000Z
DTSTAMP:20260404T110910Z
UID:MSGSUMath/24
DESCRIPTION:Title: The moduli space of generalized D-elliptic sheaves\nby Özge
Ülkem (Galatasaray University) as part of Mimar Sinan University Mathema
tics Seminars\n\n\nAbstract\nOne of the fundamental objects of the algebra
ic number theory are elliptic curves. Drinfeld defined analogues of ellipt
ic curves in the function field setting\, which are now called Drinfeld mo
dules. to prove Langlands correspondence he defined a categorically equiva
lent notion\, called elliptic sheaves\, and studied their moduli space. Si
nce then many generalizations of Drinfeld modules and elliptic sheaves hav
e been worked out. In the first part of this talk we will form the functio
n field and classical setting and discuss similarities between them. Then\
, we define Drinfeld modules\, discuss the analogy between elliptic curves
and Drinfeld modules. In the second part we talk we will define a new gen
eralization of elliptic sheaves\, called “generalized D-elliptic sheaves
” and talk on their moduli space and of the uniformization of the latter
if time permits.\n
LOCATION:https://stable.researchseminars.org/talk/MSGSUMath/24/
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