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BEGIN:VEVENT
SUMMARY:Prof. BV Rajarama Bhat (ISI Bangalore)
DTSTART;VALUE=DATE-TIME:20200819T103000Z
DTEND;VALUE=DATE-TIME:20200819T113000Z
DTSTAMP;VALUE=DATE-TIME:20230925T224242Z
UID:WOTOA/1
DESCRIPTION:Title: A
caricature of dilation theory\nby Prof. BV Rajarama Bhat (ISI Bangalor
e) as part of Webinars on Operator Theory and Operator Algebras\n\n\nAbstr
act\nWe present a set-theoretic version of some basic dilation results of
operator theory. The results we have considered are Wold decomposition\, H
almos dilation\, Sz. Nagy dilation\, inter-twining lifting\, commuting and
non-commuting dilations\, BCL theorem etc. We point out some natural gene
ralizations and variations. This is a joint work with Sandipan De and Na
rayan Rakshit.\n
LOCATION:https://researchseminars.org/talk/WOTOA/1/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Sameer Chavan (IIT Kanpur)
DTSTART;VALUE=DATE-TIME:20200909T113000Z
DTEND;VALUE=DATE-TIME:20200909T130000Z
DTSTAMP;VALUE=DATE-TIME:20230925T224242Z
UID:WOTOA/3
DESCRIPTION:Title: Di
richlet-type spaces on the unit ball and joint 2-isometries\nby Sameer
Chavan (IIT Kanpur) as part of Webinars on Operator Theory and Operator A
lgebras\n\n\nAbstract\nWe discuss a formula that relates the spherical mom
ents of the multiplication tuple on a Dirichlet-type space to a complex mo
ment problem in several variables. This can be seen as the ball-analogue o
f a formula originally invented by Richter. One may capitalize on this for
mula to study Dirichlet-type spaces on the unit ball and joint 2-isometrie
s. This talk is based on a joint work with Rajeev Gupta and Md Ramiz Reza.
\n
LOCATION:https://researchseminars.org/talk/WOTOA/3/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Sutanu Roy (NISER)
DTSTART;VALUE=DATE-TIME:20200916T113000Z
DTEND;VALUE=DATE-TIME:20200916T130000Z
DTSTAMP;VALUE=DATE-TIME:20230925T224242Z
UID:WOTOA/4
DESCRIPTION:Title: Qu
antum group contraction and bosonisation\nby Sutanu Roy (NISER) as par
t of Webinars on Operator Theory and Operator Algebras\n\n\nAbstract\nAbst
ract: In 1953 İnönü and Wigner introduced group contraction: a systema
tic (limiting) process to obtain from a given Lie group a non-isomorphic L
ie group. For example\, the contraction of SU(2) group (with respect to it
s closed subgroup T) is isomorphic to the double cover of E(2) group. The
q-deformed C*-algebraic analogue of this example was introduced and invest
igated by Woronowicz during the mid '80s to early '90s. More precisely\, t
he C*-algebraic deformations of SU(2) and (the double cover of) E(2) with
respect to real deformation parameters 0<|q|<1 become compact (denoted by
SUq(2)) and non-compact locally compact (denoted by Eq(2)) quantum groups\
, respectively. Furthermore\, the contraction of SUq(2) groups becomes (is
omorphic) to Eq(2) groups. However\, for complex deformation parameters 0<
|q|<1\, the objects SUq(2) and Eq(2) are not ordinary but braided quantum
groups. More generally\, the quantum analogue of the normal subgroup of a
semidirect product group becomes a braided quantum group and the reconstr
uction process of the semidirect product quantum group from a braided quan
tum group is called bosonisation. In this talk\, we shall present a braide
d version of the contraction procedure between SUq(2) and Eq(2) groups (fo
r complex deformation parameters 0<|q|<1) and address its compatibility wi
th bosonisation. This is based on a joint work with Atibur Rahaman.\n
LOCATION:https://researchseminars.org/talk/WOTOA/4/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Jyotishman Bhowmick (ISI Kolkata)
DTSTART;VALUE=DATE-TIME:20200923T113000Z
DTEND;VALUE=DATE-TIME:20200923T130000Z
DTSTAMP;VALUE=DATE-TIME:20230925T224242Z
UID:WOTOA/5
DESCRIPTION:Title: Me
tric-compatible connections in noncommutative geometry\nby Jyotishman
Bhowmick (ISI Kolkata) as part of Webinars on Operator Theory and Operator
Algebras\n\n\nAbstract\nLevi-Civita's theorem in Riemannian geometry stat
es that if $(M\, g)$ is a Riemannian manifold\, then there exists a unique
connection on $M$ which is torsionless and compatible with $g$. The curva
ture of the manifold is then computed from this particular connection. \n\
nWe will try to explain the notions to state and prove Levi-Civita's theor
em in the context of a noncommutative differential calculus. In particula
r\, we will describe two notions of metric-compatibility of a connection.
The talk will be based on joint works with D. Goswami\, S. Joardar\, G. La
ndi and S. Mukhopadhyay.\n\nThe geometric notions appearing in the lecture
will be defined and explained in the beginning.\n
LOCATION:https://researchseminars.org/talk/WOTOA/5/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Tirthankar Bhattacharyya (IISc Bangalore)
DTSTART;VALUE=DATE-TIME:20200930T113000Z
DTEND;VALUE=DATE-TIME:20200930T130000Z
DTSTAMP;VALUE=DATE-TIME:20230925T224242Z
UID:WOTOA/6
DESCRIPTION:Title: On
the geometry of the symmetrized bidisc\nby Tirthankar Bhattacharyya (
IISc Bangalore) as part of Webinars on Operator Theory and Operator Algebr
as\n\n\nAbstract\nWe study the action of the automorphism group of the $2$
complex dimensional manifold symmetrized bidisc $\\mathbb G$ on itself. T
he automorphism group is $3$ real dimensional. It foliates $\\mathbb G$ in
to leaves all of which are $3$ real dimensional hypersurfaces except one\,
viz.\, the royal variety. This leads us to investigate Isaev's classifica
tion of all Kobayashi-hyperbolic $2$ complex dimensional manifolds for wh
ich the group of holomorphic automorphisms has real dimension $3$ studied
by Isaev. Indeed\, we produce a biholomorphism between the symmetrized bid
isc and the domain\n\n \\[\\{(z_1\,z_2)\\in \\mathbb{C} ^2 : 1+|z_1|^2-|z_
2|^2>|1+ z_1 ^2 -z_2 ^2|\, Im(z_1 (1+\\overline{z_2}))>0\\}\\]\n\nin Isaev
's list. Isaev calls it $\\mathcal D_1$. The road to the biholomorphism is
paved with various geometric insights about $\\mathbb G$. \n\nSeveral con
sequences of the biholomorphism follow including two new characterizations
of the symmetrized bidisc and several new characterizations of $\\mathcal
D_1$. Among the results on $\\mathcal D_1$\, of particular interest is th
e fact that $\\mathcal D_1$ is a ``symmetrization''. When we symmetrize (a
ppropriately defined in the context) either $\\Omega_1$ or $\\mathcal{D}^{
(2)} _1$ (Isaev's notation)\, we get $\\mathcal D_1$. These two domains $
\\Omega_1$ and $\\mathcal{D}^{(2)} _1$ are in Isaev's list and he mentione
d that these are biholomorphic to $\\mathbb D \\times \\mathbb D$. We prod
uce explicit biholomorphisms between these domains and $\\D \\times \\D$.\
n
LOCATION:https://researchseminars.org/talk/WOTOA/6/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Mizanur Rahaman (BITS Pilani Goa campus)
DTSTART;VALUE=DATE-TIME:20201007T113000Z
DTEND;VALUE=DATE-TIME:20201007T130000Z
DTSTAMP;VALUE=DATE-TIME:20230925T224242Z
UID:WOTOA/7
DESCRIPTION:Title: Bi
synchronous Games\nby Mizanur Rahaman (BITS Pilani Goa campus) as part
of Webinars on Operator Theory and Operator Algebras\n\n\nAbstract\nFor s
ome games played by two cooperating but non-communicating players\, the pl
ayers can use entanglement as a resource to improve their outcomes beyond
what is possible classically. Graph colouring game\, graph homomorphism ga
me and graph isomorphism game are a few examples of these games. Over the
last few years\, a remarkable progress has been taken place in the theory
of these non-local games. One significant aspect of this development is it
s connection with many challenging problems in operator algebras.\n\nIn th
is talk\, I will review the theory of these games and explain the relevant
connection with operator algebras. In particular\, I will introduce a new
class of games which is called bisynchronous and will show a close connec
tion between bisynchronous games and the theory of quantum groups. Moreove
r\, when the number of inputs is equal to the number of outputs\, each bis
ynchronous correlation gives rise to a completely positive map which will
be shown to be factorable in the sense of Haagerup and Musat. This is a jo
int work with Vern Paulsen. No background in quantum theory is needed for
this talk.\n
LOCATION:https://researchseminars.org/talk/WOTOA/7/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Soumyashant Nayak (ISI Bangalore)
DTSTART;VALUE=DATE-TIME:20201014T113000Z
DTEND;VALUE=DATE-TIME:20201014T130000Z
DTSTAMP;VALUE=DATE-TIME:20230925T224242Z
UID:WOTOA/8
DESCRIPTION:Title: Wh
at is a Murray-von Neumann algebra?\nby Soumyashant Nayak (ISI Bangalo
re) as part of Webinars on Operator Theory and Operator Algebras\n\n\nAbst
ract\nIt was observed by Murray and von Neumann in their seminal paper on
rings of operators (1936) that the set of closed\, densely-defined operato
rs affiliated with a finite von Neumann algebra has the structure of a *-a
lgebra. The algebra of affiliated operators naturally appears in many cont
exts\; for instance\, in the setting of group von Neumann algebras in the
study of non-compact spaces and infinite group actions. In this talk\, we
will give an intrinsic description of Murray-von Neumann algebras avoiding
reference to a Hilbert space\, thus\, revealing the intrinsic nature of v
arious notions associated with such affiliated operators. In fact\, we wil
l view Murray-von Neumann algebras as ordered complex topological *-algebr
as arising from a functorial construction over finite von Neumann algebras
.\n
LOCATION:https://researchseminars.org/talk/WOTOA/8/
END:VEVENT
BEGIN:VEVENT
SUMMARY:S Sundar (IMSc Chennai)
DTSTART;VALUE=DATE-TIME:20201021T113000Z
DTEND;VALUE=DATE-TIME:20201021T130000Z
DTSTAMP;VALUE=DATE-TIME:20230925T224242Z
UID:WOTOA/9
DESCRIPTION:Title: An
asymmetric multiparameter CCR flow\nby S Sundar (IMSc Chennai) as par
t of Webinars on Operator Theory and Operator Algebras\n\n\nAbstract\nThe
theory of E_0-semigroups initiated by R.T. Powers and developed extensivel
y by Arveson has been an active area of research for well over thirty year
s. An E_0-semigroup is a 1-parameter semigroup of unital normal *-endomorp
hisms of B(H) where H is a Hilbert space.\n\nHowever\, nothing prevents us
from considering semigroups of endomorphisms indexed by more general sem
igroups. This was analysed in collaboration with Anbu Arjunan\, S.P. Muru
gan and R. Srinivasan. \n\nI will explain a few similarities between the
one parameter theory and the multiparameter theory. Also\, there are sign
ificant differences. I will attempt to illustrate one difference by explai
ning that a multiparameter CCR flow need not be symmetric.\n
LOCATION:https://researchseminars.org/talk/WOTOA/9/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Soumalya Joardar (IISER Kolkata)
DTSTART;VALUE=DATE-TIME:20201104T113000Z
DTEND;VALUE=DATE-TIME:20201104T130000Z
DTSTAMP;VALUE=DATE-TIME:20230925T224242Z
UID:WOTOA/11
DESCRIPTION:Title: Q
uantum symmetry of graph C* -algebras\nby Soumalya Joardar (IISER Kolk
ata) as part of Webinars on Operator Theory and Operator Algebras\n\n\nAbs
tract\nGraph C*-algebras are examples of C*-algebras generated by partial
isometries. The notion of quantum symmetry of graph C*-algebras will be di
scussed. Emphasis will be given on the invariance of KMS states of graph C
*-algebras at critical inverse temperature under such quantum symmetry. Th
e richness of quantum symmetry will be exhibited by a particular considera
tion. Also a unitary easy quantum group will be shown to appear as the qua
ntum symmetry of a particular graph C*-algebra. The talk is based on a joi
nt project with Arnab Mandal.\n
LOCATION:https://researchseminars.org/talk/WOTOA/11/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Devarshi Mukherjee (University of Goettingen)
DTSTART;VALUE=DATE-TIME:20201111T113000Z
DTEND;VALUE=DATE-TIME:20201111T130000Z
DTSTAMP;VALUE=DATE-TIME:20230925T224242Z
UID:WOTOA/12
DESCRIPTION:Title: I
soradial embeddings and non-commutative geometry\nby Devarshi Mukherje
e (University of Goettingen) as part of Webinars on Operator Theory and Op
erator Algebras\n\n\nAbstract\nIn this talk\, we describe a framework to s
tudy non-commutative geometry as a relative version of differential geomet
ry. More precisely\, given a C*-algebra A\, we would like to make sense of
a "smooth" subalgebra $A^\\infty \\subseteq A$\, and deduce properties ab
out A using such a subalgebra. Such a smooth subalgebra should be analogo
us to the Frechet algebra $C^\\infty(M) \\subseteq C(M)$ for a smooth mani
fold M\, in the world of commutative C*-algebras. We shall review the fun
damental properties and applications of such embeddings\, called $\\textit
{isoradial embeddings}$\, due to Ralf Meyer. If time permits\, I will ment
ion an ongoing research program with Meyer\, Corti\\~nas and Cuntz\, that
uses such embeddings to develop noncommutative geometry over finite fields
. \n\nI will not assume that the audience has any background beyond famil
iar examples of C*-algebras. A lot of the motivation would however be clea
rer to those familiar with cyclic homology or operator algebraic K-theory.
\n
LOCATION:https://researchseminars.org/talk/WOTOA/12/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Samya Kumar Ray (Wuhan University)
DTSTART;VALUE=DATE-TIME:20201118T113000Z
DTEND;VALUE=DATE-TIME:20201118T130000Z
DTSTAMP;VALUE=DATE-TIME:20230925T224242Z
UID:WOTOA/13
DESCRIPTION:Title: M
aximal ergodic inequalities on non-commutative L_p-spaces\nby Samya Ku
mar Ray (Wuhan University) as part of Webinars on Operator Theory and Oper
ator Algebras\n\n\nAbstract\nIn an influential paper\, Junge and Xu establ
ished a non-commutative analogue of Dunford-Schwartz maximal ergodic inequ
ality\, solving a longstanding open problem in ergodic theory. However\, t
here are very few non-commutative ergodic theorems beyond L_1-L_\\infty co
ntractions of Junge-Xu. In this talk\, we consider the problem of finding
more general non-commutative ergodic theorems than L_1-L_\\infty contracti
ons. En route we discuss how our work is related to various results of Haa
gerup\, Ruan and Pisier on non-commutative L_p spaces. This is a joint wor
k with Guixiang Hong and Simeng Wang.\n
LOCATION:https://researchseminars.org/talk/WOTOA/13/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Baruch Solel (Technion - Israel Institute of Technology)
DTSTART;VALUE=DATE-TIME:20201202T113000Z
DTEND;VALUE=DATE-TIME:20201202T130000Z
DTSTAMP;VALUE=DATE-TIME:20230925T224242Z
UID:WOTOA/14
DESCRIPTION:Title: I
nvariant subspaces for certain tuples of operators\nby Baruch Solel (T
echnion - Israel Institute of Technology) as part of Webinars on Operator
Theory and Operator Algebras\n\n\nAbstract\nIn this talk we will generaliz
e results of Sarkar and of Bhattacharjee-Eschmeier-Keshari-Sarkar concern
ing invariant subspaces for commuting tuples of operators. These authors p
rove Beurling-Lax-Halmos type results for commuting tuples $T=(T_1\,\\ldot
s\,T_d)$ operators that are contractive and pure\; that is $\\Phi_T(I)\\le
q I$ and $\\Phi_T^n(I)\\searrow 0$ where $$\\Phi_T(a)=\\Sigma_i T_iaT_i^*.
$$\n\nHere we generalize some of their results to commuting tuples $T$ sat
isfying similar conditions but for $$\\Phi_T(a)=\\Sigma_{\\alpha \\in \\m
athbb{F}^+_d} x_{|\\alpha|}T_{\\alpha}aT_{\\alpha}^*$$ where $\\{x_k\\}$ i
s a sequence of non negative numbers satisfying some natural conditions (w
here $T_{\\alpha}=T_{\\alpha(1)}\\cdots T_{\\alpha(k)}$ for $k=|\\alpha|$)
. In fact\, we deal with a more general situation where each $x_k$ is repl
aced by a $d^k\\times d^k$ matrix.\n\nWe also apply these results to subsp
aces of certain reproducing kernel correspondences $E_K$ (associated with
maps-valued kernels $K$) that are invariant under the multipliers given by
the coordinate functions.\n
LOCATION:https://researchseminars.org/talk/WOTOA/14/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Prahlad Vaidyanathan (IISER Bhopal)
DTSTART;VALUE=DATE-TIME:20201209T113000Z
DTEND;VALUE=DATE-TIME:20201209T130000Z
DTSTAMP;VALUE=DATE-TIME:20230925T224242Z
UID:WOTOA/15
DESCRIPTION:Title: R
okhlin Dimension for Group Actions on C*-algebras\nby Prahlad Vaidyana
than (IISER Bhopal) as part of Webinars on Operator Theory and Operator Al
gebras\n\n\nAbstract\nRokhlin Dimension was introduced by Hirshberg\, Wint
erand Zacharias as a higher rank version of the Rokhlin property. It maybe
thought of as a noncommutative analogue of a ‘free’ action of a group
on a topological space. We discuss this idea\, and what it means for the
corresponding crossed product C*-algebra.\n\nThe talk is meant to be expos
itory\, and accessible to a large audience.\n
LOCATION:https://researchseminars.org/talk/WOTOA/15/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Ved Prakash Gupta (JNU)
DTSTART;VALUE=DATE-TIME:20201216T113000Z
DTEND;VALUE=DATE-TIME:20201216T130000Z
DTSTAMP;VALUE=DATE-TIME:20230925T224242Z
UID:WOTOA/16
DESCRIPTION:Title: L
attice of intermediate subalgebras of a pair of simple C*-algebras\nby
Ved Prakash Gupta (JNU) as part of Webinars on Operator Theory and Operat
or Algebras\n\n\nAbstract\nThe study of the lattice of intermediate object
s of a pair $B \\subset A$ in any category is quite a natural and fundamen
tal question and has a significant say in obtaining a better understanding
of the structures of the objects A and B. A good deal of work in this dir
ection has been done in the category of finite groups\, both of qualitativ
e and quantitave flavour. Its natural analogue in the theory of operator a
lgebras has had some success\, though mainly quantitative in nature and ba
sed on some existing tools. Continuing the trend\, in a recent work with K
eshab Chandra Bakshi\, we developed certain tools in the category of simpl
e C*-algebras (motivated by and analogous to the ones existing in the cate
gory of simple von Neumann algebras) to answer a quantitative question of
Roberto Longo regarding the lattice of intermediate von Neumann subalgebra
s of an inclusion of type III factors. We shall present some essence of th
is development with an attempt to make the talk accessible to a larger aud
ience.\n
LOCATION:https://researchseminars.org/talk/WOTOA/16/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Xiang Tang (Washington University in St. Louis\, USA)
DTSTART;VALUE=DATE-TIME:20210113T040000Z
DTEND;VALUE=DATE-TIME:20210113T053000Z
DTSTAMP;VALUE=DATE-TIME:20230925T224242Z
UID:WOTOA/17
DESCRIPTION:Title: A
nalytic Grothendieck Riemann Roch Theorem\nby Xiang Tang (Washington U
niversity in St. Louis\, USA) as part of Webinars on Operator Theory and O
perator Algebras\n\n\nAbstract\nIn this talk\, we will introduce an intere
sting index problem naturally associated to the Arveson-Douglas conjecture
in functional analysis. This index problem is a generalization of the cla
ssical Toeplitz index theorem and connects to many different branches of M
athematics. In particular\, it can be viewed as an analytic version of the
Grothendieck Riemann Roch theorem. This is joint work with R. Douglas\, M
. Jabbari\, and G. Yu.\n
LOCATION:https://researchseminars.org/talk/WOTOA/17/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Sugato Mukhopadhyay (ISI Kolkata)
DTSTART;VALUE=DATE-TIME:20210120T113000Z
DTEND;VALUE=DATE-TIME:20210120T130000Z
DTSTAMP;VALUE=DATE-TIME:20230925T224242Z
UID:WOTOA/18
DESCRIPTION:Title: L
evi-Civita connections on bicovariant differential calculus\nby Sugato
Mukhopadhyay (ISI Kolkata) as part of Webinars on Operator Theory and Ope
rator Algebras\n\n\nAbstract\nIn this talk\, we will propose a definition
of Levi-Civita connections on bicovariant differential calculi of Hopf alg
ebras\, which satisfy a technical property. Given a bi-invariant metric on
such a calculus\, we will present a sufficient condition for the existenc
e of a unique bicovariant Levi-Civita connection on the calculus. We will
discuss examples of Hopf algebras that fit into this framework. This talk
is based on a joint work with Jyotishman Bhowmick.\n
LOCATION:https://researchseminars.org/talk/WOTOA/18/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Apoorva Khare (IISc Bangalore)
DTSTART;VALUE=DATE-TIME:20210303T113000Z
DTEND;VALUE=DATE-TIME:20210303T130000Z
DTSTAMP;VALUE=DATE-TIME:20230925T224242Z
UID:WOTOA/19
DESCRIPTION:Title: T
otal positivity: history\, basics\, and modern connections\nby Apoorva
Khare (IISc Bangalore) as part of Webinars on Operator Theory and Operato
r Algebras\n\n\nAbstract\nI will give a gentle introduction to totally pos
itive matrices and Polya frequency functions. This includes basic examples
\, history\, and fundamental results on total positivity\, variation dimin
ution\, and sign non-reversal – as well as a few proofs to show how the
main ingredients fit together. Many classical results (and one Hypothesis)
from before 1955 feature in this journey. I will end by describing how Po
lya frequency functions connect to the Laguerre–Polya class and hence Po
lya–Schur multipliers\, and mention 21st century incarnations of the lat
ter.\n
LOCATION:https://researchseminars.org/talk/WOTOA/19/
END:VEVENT
BEGIN:VEVENT
SUMMARY:CR Jayanarayanan (IIT Palakkad)
DTSTART;VALUE=DATE-TIME:20210310T113000Z
DTEND;VALUE=DATE-TIME:20210310T130000Z
DTSTAMP;VALUE=DATE-TIME:20230925T224242Z
UID:WOTOA/20
DESCRIPTION:by CR Jayanarayanan (IIT Palakkad) as part of Webinars on Oper
ator Theory and Operator Algebras\n\nAbstract: TBA\n
LOCATION:https://researchseminars.org/talk/WOTOA/20/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Anshu Nirbhay (IISER Bhopal)
DTSTART;VALUE=DATE-TIME:20210317T113000Z
DTEND;VALUE=DATE-TIME:20210317T130000Z
DTSTAMP;VALUE=DATE-TIME:20230925T224242Z
UID:WOTOA/21
DESCRIPTION:Title: S
ome Dimension Theories of C*-algebras and Rokhlin-type Properties\nby
Anshu Nirbhay (IISER Bhopal) as part of Webinars on Operator Theory and Op
erator Algebras\n\n\nAbstract\nThere are many ranks associated with a $C^*
$-algebra. Rieffel defined the notion of stable ranks in the 1980s. We wil
l mainly focus on two of these ranks namely connected stable rank and gene
ral stable rank. If we are given a group $G$\, which acts on a $C^*$-algeb
ra $A$ via a map $\\alpha$\, the triple $(A\, G\, \\alpha)$ is said to be
a $C^*$-dynamical system\, then we can associate a $C^*$-algebra called a
crossed product $C^*$-algebra denoted by $A \\rtimes_{\\alpha}G$. We will
discuss the homotopical stable ranks of a crossed product $C^*$-algebra by
a finite group where the action involved has Rokhlin-type property.\n
LOCATION:https://researchseminars.org/talk/WOTOA/21/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Keshab Chandra Bakshi (Chennai Mathematical Institute)
DTSTART;VALUE=DATE-TIME:20210324T113000Z
DTEND;VALUE=DATE-TIME:20210324T130000Z
DTSTAMP;VALUE=DATE-TIME:20230925T224242Z
UID:WOTOA/22
DESCRIPTION:Title: O
n a question of Vaughan Jones\nby Keshab Chandra Bakshi (Chennai Mathe
matical Institute) as part of Webinars on Operator Theory and Operator Alg
ebras\n\n\nAbstract\nGiven a subgroup H of a finite group G\, as an applic
ation of famous Hall's Marriage Theorem\, we can obtain a set of coset rep
resentatives which acts simultaneously as representatives of both left an
d right cosets of H in G. Given a subfactor $N\\subset M$ with finite Jone
s index\, M can be regarded as a left as well as a right N-module. Pimsner
and Popa proved that M is finitely generated as a left (equivalently\, ri
ght) N-module. About a decade back\, Vaughan Jones asked whether one can f
ind a common set which acts simultaneously as a left and a right generatin
g set. As a naive attempt in this direction\, we answer this question in t
he affirmative for a large class of integer index subfactors. We also disc
uss some applications of our results.\n
LOCATION:https://researchseminars.org/talk/WOTOA/22/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Apurva Seth (IISER Bhopal)
DTSTART;VALUE=DATE-TIME:20210331T113000Z
DTEND;VALUE=DATE-TIME:20210331T130000Z
DTSTAMP;VALUE=DATE-TIME:20230925T224242Z
UID:WOTOA/23
DESCRIPTION:Title: A
F- algebras and Rational Homotopy Theory\nby Apurva Seth (IISER Bhopal
) as part of Webinars on Operator Theory and Operator Algebras\n\n\nAbstra
ct\nIn this talk\, we will give a procedure to compute the rational homoto
py group of the group of quasi-unitaries of an AF-algebra. As an applicati
on\, we show that an AF-algebra is K-stable if and only if it is rationall
y K-stable.\n
LOCATION:https://researchseminars.org/talk/WOTOA/23/
END:VEVENT
END:VCALENDAR