Search Results - "Kell, Martin"
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1
Transport maps, non-branching sets of geodesics and measure rigidity
Published in Advances in mathematics (New York. 1965) (07-11-2017)“…In this paper we investigate the relationship between a general existence of transport maps of optimal couplings with absolutely continuous first marginal and…”
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2
Symmetric orthogonality and non-expansive projections in metric spaces
Published in Manuscripta mathematica (01-01-2020)“…In this paper known results of symmetric orthogonality, as introduced by G. Birkhoff, and non-expansive nearest point projections are extended from the linear…”
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3
Uniformly Convex Metric Spaces
Published in Analysis and Geometry in Metric Spaces (01-01-2014)“…In this paper the theory of uniformly convex metric spaces is developed. These spaces exhibit ageneralized convexity of the metric from a fixed point. Using a…”
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4
Representation of Markov chains by random maps: existence and regularity conditions
Published in Calculus of variations and partial differential equations (01-11-2015)“…We systematically investigate the problem of representing Markov chains by families of random maps, and which regularity of these maps can be achieved…”
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5
q-Heat flow and the gradient flow of the Renyi entropy in the p-Wasserstein space
Published in Journal of functional analysis (15-10-2016)“…Based on the idea of a recent paper by Ambrosio–Gigli–Savaré (2014) [5], we show that the L2-gradient flow of the q-Cheeger energy, called q-heat flow, solves…”
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6
Sectional Curvature-Type Conditions on Metric Spaces
Published in The Journal of geometric analysis (15-01-2019)“…In the first part Busemann concavity as non-negative curvature is introduced and a bi-Lipschitz splitting theorem is shown. Furthermore, if the Hausdorff…”
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7
On the structure of $$\mathrm {RCD}$$ spaces with upper curvature bounds
Published in Mathematische Zeitschrift (01-08-2022)“…We develop a structure theory for $$\mathrm {RCD}$$ RCD spaces with curvature bounded above in Alexandrov sense. In particular, we show that any such space is…”
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8
On the structure of RCD spaces with upper curvature bounds
Published in Mathematische Zeitschrift (2022)“…We develop a structure theory for RCD spaces with curvature bounded above in Alexandrov sense. In particular, we show that any such space is a topological…”
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9
A notion of nonpositive curvature for general metric spaces
Published in Differential geometry and its applications (01-02-2015)“…We introduce a new definition of nonpositive curvature in metric spaces and study its relation to the existing notions of nonpositive curvature in comparison…”
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10
Transport maps, non-branching sets of geodesics and measure rigidity
Published 18-04-2017“…In this paper we investigate the relationship between a general existence of transport maps of optimal couplings with absolutely continuous first marginal and…”
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Journal Article -
11
Symmetric orthogonality and non-expansive projections in metric spaces
Published 07-04-2016“…In this paper known results of symmetric orthogonality, as introduced by G. Birkhoff, and non-expansive nearest point projections are extended from the linear…”
Get full text
Journal Article -
12
Sectional curvature-type conditions on metric spaces
Published 13-01-2016“…In the first part Busemann concavity as non-negative curvature is introduced and a bi-Lipschitz splitting theorem is shown. Furthermore, if the Hausdorff…”
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13
On Cheeger and Sobolev differentials in metric measure spaces
Published 02-12-2015“…Recently Gigli developed a Sobolev calculus on non-smooth spaces using module theory. In this paper it is shown that his theory fits nicely into the theory of…”
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14
On the existence of dual solutions for Lorentzian cost functions
Published 13-08-2018“…The dual problem of optimal transportation in Lorentz-Finsler geometry is studied. It is shown that in general no solution exists even in the presence of an…”
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15
A note on non-negatively curved Berwald spaces
Published 12-02-2015“…In this note it is shown that Berwald spaces admitting the same norm-preserving torsion-free affine connection have the same (weighted) Ricci curvatures…”
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16
Uniformly convex metric spaces
Published 12-06-2014“…In this paper the theory of uniformly convex metric spaces is developed. These spaces exhibit a generalized convexity of the metric from a fixed point. Using a…”
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17
On Interpolation and Curvature via Wasserstein Geodesics
Published 06-01-2014“…In this article, a proof of the interpolation inequality along geodesics in $p$-Wasserstein spaces is given. This interpolation inequality was the main…”
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18
q-heat flow and the gradient flow of the Renyi entropy in the p-Wasserstein space
Published 04-01-2014“…Based on the idea of a recent paper by Ambrosio-Gigli-Savar\'e in Invent. Math. (2013), we show that flow of the $q$-Cheeger energy, called $q$-heat flow,…”
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19
On the volume measure of non-smooth spaces with Ricci curvature bounded below
Published 20-01-2017“…Ann. Sc. Norm. Super. Pisa Cl. Sci. (5) 18 (2018), no. 2, 593-610 We prove that, given an $RCD^{*}(K,N)$-space $(X,d,m)$, then it is possible to…”
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20
A Note on Lipschitz Continuity of Solutions of Poisson Equations in Metric Measure Spaces
Published 08-07-2013“…In this note we show how to adjust some proofs of Koskela et. al 2003 and Jiang 2011 in order to show that in certain spaces $(X,d,\mu)$, like…”
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