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20072026
most citedRiemannian Ricci curvature lower bounds in metric measure spaces with -finite measure

206 citations · 394 across the 45 of their papers we have counts for

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11 papers · 1 filter

math.FA2025

Planar -extension domains

Pekka Koskela, Tapio Rajala, Yi Ru-Ya Zhang

We show that a bounded planar simply connected domain is a -extension domain if and only if for every pair of points in there exists a curve $γ\subset Ω^…

math.FA2023

Vector calculus on weighted reflexive Banach spaces

Enrico Pasqualetto, Tapio Rajala

We study first-order Sobolev spaces on reflexive Banach spaces via relaxation, test plans, and divergence. We show the equivalence of the different approaches to the Sobolev spaces…

math.FA2022

Tensorization of quasi-Hilbertian Sobolev spaces

Sylvester Eriksson-Bique, Tapio Rajala, Elefterios Soultanis

The tensorization problem for Sobolev spaces asks for a characterization of how the Sobolev space on a product metric measure space can be determined from its factors.…

math.FA2021

Removability of product sets for Sobolev functions in the plane

Tapio Rajala, Ugo Bindini

We study conditions on closed sets making the product removable or non-removable for . The main results show that the Hausdorff-dimen…

math.FA2021

Bi-Lipschitz invariance of planar - and -extension domains

Miguel García-Bravo, Tapio Rajala, Zheng Zhu

We prove that a bi-Lipschitz image of a planar -extension domain is also a -extension domain, and that a bi-Lipschitz image of a planar -extension domain is again…

math.FA2020

Characterisation of upper gradients on the weighted Euclidean space and applications

Danka Lučić, Enrico Pasqualetto, Tapio Rajala

In the context of Euclidean spaces equipped with an arbitrary Radon measure, we prove the equivalence among several different notions of Sobolev space present in the literature and…

math.FA2018

A density result on Orlicz-Sobolev spaces in the plane

Walter A. Ortiz, Tapio Rajala

We show the density of smooth Sobolev functions in the Orlicz-Sobolev spaces for bounded simply connected planar domains and doub…

math.FA2018

Restricting open surjections

Jesus A. Jaramillo, Enrico Le Donne, Tapio Rajala

We show that any continuous open surjection from a complete metric space to another metric space can be restricted to a surjection for which the domain has the same density charact…

math.FA2018

A density result for homogeneous Sobolev spaces on planar domains

Debanjan Nandi, Tapio Rajala, Timo Schultz

We show that in a bounded simply connected planar domain the smooth Sobolev functions are dense in the homogeneous Sobolev spaces …

math.FA2016

A density problem for Sobolev spaces on Gromov hyperbolic domains

Pekka Koskela, Tapio Rajala, Yi Ru-Ya Zhang

We prove that for a bounded domain which is Gromov hyperbolic with respect to the quasihyperbolic metric, especially when is a finitely connected planar…

math.FA2012

Radon-Nikodym property and area formula for Banach homogeneous group targets

Valentino Magnani, Tapio Rajala

We prove a Rademacher-type theorem for Lipschitz mappings from a subset of a Carnot group to a Banach homogeneous group, equipped with a suitably weakened Radon-Nikodym property. W…