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SUMMARY:Daniel Luckhardt (Ben-Gurion University)
DTSTART;VALUE=DATE-TIME:20200605T150000Z
DTEND;VALUE=DATE-TIME:20200605T160000Z
DTSTAMP;VALUE=DATE-TIME:20200812T061301Z
UID:mmsANDconv/1
DESCRIPTION:Title: A volume comparison theorem for characteristic numbers\
nby Daniel Luckhardt (Ben-Gurion University) as part of mms&convergence\n\
n\nAbstract\nWe show that assuming lower bounds on the Ricci curvature and
the\ninjectivity radius the absolute value of any \ncharacteristic number
of a Riemannian manifold M is bounded \nproportional to the volume\, i.e.
bounded by Cvol(M) where C \ndepends only on the characteristic number\,
\nthe dimension of M\, and both bounds. The proof relies \non the definit
ion of a connection for an harmonic Hölder \nregular metric tensor as the
y appear for instance as \nGromov-Hausdorff limits of Riemannian manifolds
.\n
END:VEVENT
BEGIN:VEVENT
SUMMARY:Christian Ketterer (Toronto University)
DTSTART;VALUE=DATE-TIME:20200612T150000Z
DTEND;VALUE=DATE-TIME:20200612T160000Z
DTSTAMP;VALUE=DATE-TIME:20200812T061301Z
UID:mmsANDconv/2
DESCRIPTION:Title: Applications of needle decomposition for metric measure
spaces\nby Christian Ketterer (Toronto University) as part of mms&converg
ence\n\n\nAbstract\nIn this talk I show how one can formulate and prove th
e\nHeintze-Karcher inequality in the context of nonsmooth spaces that\nsat
isfy a Ricci curvature bound in the sense of Lott\, Sturm and\nVillani. As
a by-product one obtains a notion of mean curvature for\nthe boundary of
Borel sets in such spaces. My approach is based on the\nneedle decompositi
on method introduced for this framework by\nCavalletti and Mondino.\n
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BEGIN:VEVENT
SUMMARY:Sergio Zamora (Penn State University)
DTSTART;VALUE=DATE-TIME:20200619T150000Z
DTEND;VALUE=DATE-TIME:20200619T160000Z
DTSTAMP;VALUE=DATE-TIME:20200812T061301Z
UID:mmsANDconv/3
DESCRIPTION:Title: Fundamental Groups and Limits of Almost Homogeneous Spa
ces\nby Sergio Zamora (Penn State University) as part of mms&convergence\n
\n\nAbstract\nWe show that for a sequence of proper length spaces $X_n$ wi
th groups $\\Gamma_n$ acting discretely and almost transitively by isometr
ies\, if they converge to a proper finite dimensional length space $X$\, t
hen $X$ is a nilpotent Lie group with an invariant sub-Finsler Carnot metr
ic. Also\, for large enough $n$\, there are subgroups $\\Lambda_n \\leq \\
pi_1(X_n)$ and surjective morphisms $\\Lambda_n\\to \\pi_1(X)$.\n
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BEGIN:VEVENT
SUMMARY:Ilaria Mondello (Université de Paris Est Créteil)
DTSTART;VALUE=DATE-TIME:20200626T150000Z
DTEND;VALUE=DATE-TIME:20200626T160000Z
DTSTAMP;VALUE=DATE-TIME:20200812T061301Z
UID:mmsANDconv/4
DESCRIPTION:Title: Ricci limit spaces : an introduction to the tools of Ch
eeger-Jiang-Naber's work\nby Ilaria Mondello (Université de Paris Est Cr
éteil) as part of mms&convergence\n\n\nAbstract\nThe goal of this exposit
ory talk is to explain parts of the work of J. Cheeger\, W. Jiang and A. N
aber:\nhttps://arxiv.org/abs/1805.07988 For a converging\, non-collapsing
sequence of Riemannian manifolds with a uniform Ricci lower bound\, they p
roved that singular strata of the limit space are rectifiable. Some of the
key tools in the proof include quantitative stratification\, which was fi
rst introduced in previous work of Cheeger-Naber\, and new related volume
estimates\, together with a precise study of neck regions. After a brief r
eview of Cheeger-Colding theory\, the talk will focus on explaining the no
tions of quantitative stratifications\, neck regions and their role in the
proof.\n
END:VEVENT
BEGIN:VEVENT
SUMMARY:Brian Allen (University of Hartford)
DTSTART;VALUE=DATE-TIME:20200703T150000Z
DTEND;VALUE=DATE-TIME:20200703T160000Z
DTSTAMP;VALUE=DATE-TIME:20200812T061301Z
UID:mmsANDconv/5
DESCRIPTION:Title: Null Distance and Convergence of Warped Product Spaceti
mes\nby Brian Allen (University of Hartford) as part of mms&convergence\n\
n\nAbstract\nThe null distance was introduced by Christina Sormani and Car
los Vega as a way of turning a spacetime into a metric space. This is part
icularly important for geometric stability questions relating to spacetime
s such as the stability of the positive mass theorem. In this talk\, we wi
ll describe the null distance\, present properties of the metric space str
ucture\, and examine the convergence of sequences of warped product spacet
imes equipped with the null distance. This is joint work with Annegret Bur
tscher.\n
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