activity
20192026
most citedA note on metric-measure spaces supporting Poincaré inequalities

2 citations · 3 across the 13 of their papers we have counts for

collaborators

13 papers

math.FA2026

A purely metric characterization of supercritical Sobolev spaces

Ryan Alvarado, Efstathios Konstantinos Chrontsios Garitsis

In this paper we provide a purely metric and derivative-free characterization of continuous mappings in the local supercritical Sobolev space. More specifically, we show that a con…

math.AP2026

The Trudinger inequality is true for spaces

Ryan Alvarado, Ahmed Dughayshim, Piotr Hajłasz

We prove the Trudinger inequality with exponent for Sobolev spaces on metric measure spaces under the sole measure growth assumption .…

math.CA2026

On the measure of the boundary of a Hajłasz-Sobolev -extension domain

Ryan Alvarado, Riddhi Mishra

We prove that the boundary of every bounded -extension domain in a -doubling metric measure space has measure zero whenever , with the additiona…

math.FA2026

Real-Variable Theory of Hardy--Lorentz Spaces on Quasi-Ultrametric Spaces of Homogeneous Type with Reverse-Doubling Property

Chenfeng Zhu, Ryan Alvarado, Xianjie Yan +2

Let be an ultra-RD-space with upper dimension ; i.e., it is a quasi-ultrametric space of homogeneous type whose measure satisfies an addition…

math.FA2026

Embeddings of variable Sobolev, Besov, and Triebel-Lizorkin spaces on metric measure spaces

Ryan Alvarado, Michał Dymek, Przemysław Górka +1

Sobolev-type embeddings on metric measure spaces encode a subtle interaction between the analytic regularity of functions and the geometry of the underlying domain space. In this p…

math.CA2025

On the dimension distortion under fractionally smooth mappings

Ryan Alvarado, Efstathios Konstantinos Chrontsios Garitsis

We determine the extent to which certain classes of fractionally `smooth' continuous mappings between metric spaces distort various dimensions, including the Hausdorff, upper Minko…

math.FA2022

A simple proof of reflexivity and separability of Sobolev spaces

Ryan Alvarado, Piotr Hajłasz, Lukáš Malý

We present an elementary proof of a well-known theorem of Cheeger which states that if a metric-measure space supports a -Poincaré inequality, then the Sobolev…

math.FA2022

A Measure Characterization of Embedding and Extension Domains for Sobolev, Triebel-Lizorkin, and Besov Spaces on Spaces of Homogeneous Type

Ryan Alvarado, Dachun Yang, Wen Yuan

In this article, for an optimal range of the smoothness parameter that depends (quantitatively) on the geometric makeup of the underlying space, the authors identify purely mea…

math.FA2022

Optimal Embeddings for Triebel-Lizorkin and Besov Spaces on Quasi-Metric Measure Spaces

Ryan Alvarado, Dachun Yang, Wen Yuan

In this article, via certain lower bound conditions on the measures under consideration, the authors fully characterize the Sobolev embeddings for the scales of Hajłasz-Triebel-Liz…

math.FA2022

Pointwise Characterization of Besov and Triebel-Lizorkin Spaces on Spaces of Homogeneous Type

Ryan Alvarado, Fan Wang, Dachun Yang +1

In this article, the authors establish the pointwise characterization of Besov and Triebel-Lizorkin spaces on spaces of homogeneous type via clarifying the relationship among Hajła…

math.CO2020

The Game of Cycles

Ryan Alvarado, Maia Averett, Benjamin Gaines +5

The Game of Cycles, introduced by Su (2020), is played on a simple connected planar graph together with its bounded cells, and players take turns marking edges with arrows accordin…

math.FA2019★ 1 cited

Sobolev embedding for spaces is equivalent to a lower bound of the measure

Ryan Alvarado, Przemysław Górka, Piotr Hajłasz

It has been known since 1996 that a lower bound for the measure, , implies Sobolev embedding theorems for Sobolev spaces defined on metric-measure spa…

math.FA2019★ 2 cited

A note on metric-measure spaces supporting Poincaré inequalities

Ryan Alvarado, Piotr Hajłasz

Using a method of Korobenko, Maldonado and Rios we show a new characterization of doubling metric-measure spaces supporting Poincaré inequalities without assuming a priori that the…