BEGIN:VCALENDAR
VERSION:2.0
PRODID:researchseminars.org
CALSCALE:GREGORIAN
X-WR-CALNAME:researchseminars.org
BEGIN:VEVENT
SUMMARY:Jie Xiao (Memorial University of Newfoundland)
DTSTART:20220913T010000Z
DTEND:20220913T020000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/1
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/1/">Mean Hoelder-Lipschitz Potentials in Curved Camp
 anato-Radon Spaces</a>\nby Jie Xiao (Memorial University of Newfoundland) 
 as part of Nonlinear Analysis Seminar Series\n\nLecture held in Room M210 
 in NTNU Gongguan Campus Mathematics Building.\n\nAbstract\nThis talk will 
 present L. Liu-J. Xiao's  article: Math. Ann. 375(2019)1045-1077\, proving
  that for $s \\in (0\,1)$\, $\\alpha \\in (0\,n)$\, $\\beta \\in (0\,n]$\,
  \n\\[\n1\\leq \\min\\{p\, q\\}\\le\\max\\{p\,q\\}<\\beta p(n-\\alpha p)^{
 -1}<\\infty\n\\]\nand $\\lambda=q(np^{-1}-s-\\alpha)+n-\\beta$\, if $\\mu$
  is a nonnegative Radon measure on $\\mathbb R^n$ with the $\\beta$-dimens
 ional upper curvature $|\\|\\mu|\\|_\\beta<\\infty$ then $I_\\alpha \\dot{
 \\varLambda}_s^{p\,\\infty}$ (the mean Hoelder-Lipschitz potential space o
 n $\\mathbb R^n$) embeds continuously into $\\mathcal{L}^{q\,\\lambda}_\\m
 u$ (the curved Campanato-Radon space on $\\mathbb R^n$)\; and yet its conv
 erse is still valid with $\\mu$ being admissible\, thereby discovering\nth
 e $\\gamma$-Hoelder-Lipschitz continuity of any duality solution to the $\
 \alpha$-th Laplace equation $(-\\varDelta)^{\\frac\\alpha 2}u=\\mu$\nor th
 e $[1\,n/2)\\cap\\{1\,2...\,n\\}\\ni k$-th Hessian equation $F_k[u]=\\mu$ 
 under a suitable curvature $|\\||\\mu|\\||_\\beta<\\infty$.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/1/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Alexander Volberg (Michigan State University)
DTSTART:20220920T010000Z
DTEND:20220920T020000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/2
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/2/">Dyadic rectangles</a>\nby Alexander Volberg (Mic
 higan State University) as part of Nonlinear Analysis Seminar Series\n\nLe
 cture held in Room M210 in NTNU Gongguan Campus Mathematics Building.\n\nA
 bstract\nWeighted Carleson embedding (weighted paraproduct estimates in an
 other language)  lies in the core of various harmonic analysis and PDE res
 ults. Not much is known about it in multi-parameter situation\, while one 
 parameter is completely understood. I will formulate several new results o
 n weighted multi-parameter Carleson embedding on multi-trees and their cor
 ollaries as embeddings of Hilbert spaces of analytic functions on poly-dis
 cs.\n\nI will also formulate corresponding Poincar\\'e inequalities on mul
 ti-trees and poly-discs. Some of those results are final\, but even embedd
 ing of Hardy space on bi-disc is not completely described. My presentation
  is based on joint works with  N. Arcozzi\, I. Holmes\, P. Mozolyako\, P. 
 Zorin-Kranich.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/2/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Lenka Slavikova (Charles University)
DTSTART:20220927T070000Z
DTEND:20220927T080000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/3
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/3/">Classical multiplier theorems and their sharp va
 riants</a>\nby Lenka Slavikova (Charles University) as part of Nonlinear A
 nalysis Seminar Series\n\nLecture held in Room M210 in NTNU Gongguan Campu
 s Mathematics Building.\n\nAbstract\nThe question of finding good sufficie
 nt conditions on a bounded function $m$ guaranteeing the $L^p$-boundedness
  of the associated Fourier multiplier operator is a long-standing open pro
 blem in harmonic analysis. In this talk\, I will recall the classical mult
 iplier theorems of H\\"ormander and Marcinkiewicz and present their sharp 
 variants in which the multiplier belongs to a certain fractional Sobolev s
 pace. The talk is based in part on a joint work with L. Grafakos and M. Ma
 sty\\l o.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/3/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Francesco Maggi (UT Austin)
DTSTART:20221004T010000Z
DTEND:20221004T020000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/4
DESCRIPTION:by Francesco Maggi (UT Austin) as part of Nonlinear Analysis S
 eminar Series\n\nLecture held in Room M210 in NTNU Gongguan Campus Mathema
 tics Building.\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/4/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Jin-Cheng Jiang (National Tsing Hua University)
DTSTART:20221018T070000Z
DTEND:20221018T080000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/5
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/5/">On the Cauchy problem for the cutoff Boltzmann e
 quation with small initial data</a>\nby Jin-Cheng Jiang (National Tsing Hu
 a University) as part of Nonlinear Analysis Seminar Series\n\nLecture held
  in Room M210 in NTNU Gongguan Campus Mathematics Building.\n\nAbstract\nW
 e prove the global existence of the non-negative unique mild\nsolution for
  the Cauchy problem of the cutoff Boltzmann equation for\nsoft potential m
 odel −1<=γ<0 with the small initial data in three\ndimensional space. T
 hus our result fixes the gap for the case γ=−1 in\nthree dimensional sp
 ace in the authors' previous work where the estimate\nfor the loss term wa
 s improperly used. The other gap there for the case\nγ=0 in two dimension
 al space is recently fixed by Chen\, Denlinger and\nPavlović. The initial
  data f0 is non-negative\, small in weighted\nL3_{x\,v} and finite in weig
 hted L15/8_{x\,v}. We also show that the\nsolution scatters with respect t
 o the kinetic transport operator. The\nnovel contribution of this work lie
 s in the exploration of the symmetric\nproperty of the gain term in terms 
 of weighted estimate. It is the key\ningredient for solving the model −1
 <γ<0 when applying the Strichartz\nestimates.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/5/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Neal Bez (Saitama University)
DTSTART:20221129T010000Z
DTEND:20221129T033000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/6
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/6/">An introduction to Strichartz estimates I</a>\nb
 y Neal Bez (Saitama University) as part of Nonlinear Analysis Seminar Seri
 es\n\nLecture held in Room M210 in NTNU Gongguan Campus Mathematics Buildi
 ng.\n\nAbstract\nThe aim of these lectures is to give a gentle introductio
 n to Strichartz estimates\, with an emphasis on particular cases such as t
 he linear Schr\\"odinger and wave equations. The associated dispersive est
 imates play a highly important role in the theory of Strichartz estimates 
 so I will begin in Lecture 1 by proving the required dispersive estimates.
 \n\nNext\, in Lecture 2\, I will prove the homogeneous Strichartz estimate
 s in all admissible cases\, including the so-called Keel--Tao endpoint cas
 e. Building on the content of the first two lectures\, in Lecture 3\, I wi
 ll discuss the situation regarding inhomogeneous Strichartz estimates.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/6/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Neal Bez (Saitama University)
DTSTART:20221206T010000Z
DTEND:20221206T033000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/7
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/7/">An introduction to Strichartz estimates II</a>\n
 by Neal Bez (Saitama University) as part of Nonlinear Analysis Seminar Ser
 ies\n\nLecture held in Room M210 in NTNU Gongguan Campus Mathematics Build
 ing.\n\nAbstract\nThe aim of these lectures is to give a gentle introducti
 on to Strichartz estimates\, with an emphasis on particular cases such as 
 the linear Schr\\"odinger and wave equations. The associated dispersive es
 timates play a highly important role in the theory of Strichartz estimates
  so I will begin in Lecture 1 by proving the required dispersive estimates
 .\n\nNext\, in Lecture 2\, I will prove the homogeneous Strichartz estimat
 es in all admissible cases\, including the so-called Keel--Tao endpoint ca
 se. Building on the content of the first two lectures\, in Lecture 3\, I w
 ill discuss the situation regarding inhomogeneous Strichartz estimates.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/7/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Neal Bez (Saitama University)
DTSTART:20221213T010000Z
DTEND:20221213T033000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/8
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/8/">An introduction to Strichartz estimates III</a>\
 nby Neal Bez (Saitama University) as part of Nonlinear Analysis Seminar Se
 ries\n\nLecture held in Room M210 in NTNU Gongguan Campus Mathematics Buil
 ding.\n\nAbstract\nThe aim of these lectures is to give a gentle introduct
 ion to Strichartz estimates\, with an emphasis on particular cases such as
  the linear Schr\\"odinger and wave equations. The associated dispersive e
 stimates play a highly important role in the theory of Strichartz estimate
 s so I will begin in Lecture 1 by proving the required dispersive estimate
 s.\n\nNext\, in Lecture 2\, I will prove the homogeneous Strichartz estima
 tes in all admissible cases\, including the so-called Keel--Tao endpoint c
 ase. Building on the content of the first two lectures\, in Lecture 3\, I 
 will discuss the situation regarding inhomogeneous Strichartz estimates.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/8/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Lubos Pick (Charles University)
DTSTART:20221108T070000Z
DTEND:20221108T080000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/9
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/9/">Optimality problems in Orlicz spaces</a>\nby Lub
 os Pick (Charles University) as part of Nonlinear Analysis Seminar Series\
 n\nLecture held in Room M210 in NTNU Gongguan Campus Mathematics Building.
 \n\nAbstract\nWe prove a general principle\, called the principal alternat
 ive\, which yields an easily verifiable necessary and sufficient condition
  for the existence or the non-existence of an optimal Orlicz space in a wi
 de variety of specific tasks including boundedness of operators. We show t
 hat the key relation is the positioning of certain rearrangement-invariant
  space\, characteristic for the task in question\, to its fundamental Orli
 cz space. The main motivation stems from the imbalance between the express
 ivity\, meaning the richness and versatility\, of certain class of functio
 n spaces\, and its accessibility\, i.e.\, its complexity and technical dif
 ficulty. More precisely\, while an optimal rearrangement-invariant space i
 n a given task often exists\, it might be too complicated or too implicit 
 to be of any practical value. Optimal Orlicz spaces\, on the other hand\, 
 are simpler and more manageable for applications\, but they tend not to ex
 ist at all. We apply the general abstract result to several specific tasks
  including continuity of Sobolev embeddings or boundedness of integral ope
 rators such as the Hardy-Littlewood maximal operator and the Laplace trans
 form. The proof of the principal alternative is based on relations of endp
 oint Lorentz spaces to unions or intersections of Orlicz spaces. This is a
  joint work with Vít Musil (Brno) and Jakub Takáč (Warwick).\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/9/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Tess Anderson (Carnegie Mellon University)
DTSTART:20221025T010000Z
DTEND:20221025T020000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/10
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/10/">Analysis and number theory team up</a>\nby Tess
  Anderson (Carnegie Mellon University) as part of Nonlinear Analysis Semin
 ar Series\n\nLecture held in Room M210 in NTNU Gongguan Campus Mathematics
  Building.\n\nAbstract\nWe discuss two ways that analysis and number theor
 y have recently teamed up\, using a back and forth interplay to make progr
 ess on two different types of counting problems. First we will count equil
 ateral triangles in Euclidean space. Second we will determine how often a 
 random polynomial fails to have "full" Galois group. Though easy to state\
 , these questions have generated a lot of interesting techniques through t
 he years\, which we will glimpse during this talk.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/10/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Carolin Kreisbeck (Katholischen Universität Eichstätt - Ingolsta
 dt)
DTSTART:20221101T070000Z
DTEND:20221101T080000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/11
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/11/">Dealing with nonlocalities in variational funct
 ionals: Convexity notions\, lower semicontinuity\, and relaxation</a>\nby 
 Carolin Kreisbeck (Katholischen Universität Eichstätt - Ingolstadt) as p
 art of Nonlinear Analysis Seminar Series\n\nLecture held in Room M210 in N
 TNU Gongguan Campus Mathematics Building.\n\nAbstract\nNonlocal variationa
 l problems arise in various applications\, such as continuum mechanics\, t
 he theory of phase transitions\, or image processing. Naturally\, the pres
 ence of nonlocalities leads to new effects\, and the standard methods in t
 he calculus of variations\, which tend to rely intrinsically on localizati
 on arguments\, do not apply. In this talk\, we address questions arising f
 rom the existence theory for three different classes of variational functi
 onals: integrals depending on Riesz fractional gradients\, double integral
 s\, and double supremals - and find qualitatively very different results. 
 Regarding the characterization of weak lower semicontinuity\, it may be su
 rprising that quasiconvexity\, which is well-known from the classical loca
 l setting\, also provides the correct convexity notion for the fractional 
 integrals. Our proof relies on a translation mechanism that allows switchi
 ng between classical and fractional gradients. In the case of double supre
 mals\, we show that the natural guess of separate level convexity fails in
  the vectorial case\, and introduce the new Cartesian level convexity. As 
 for relaxation\, we discuss the central issue of why one cannot expect the
 se nonlocal functionals\, in contrast to their local counterparts\, to be 
 structure-preserving. This is based on joint work with Antonella Ritorto\,
  Hidde Schönberger (both KU Eichstätt-Ingolstadt)\, and Elvira Zappale (
 Sapienza University of Rome).\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/11/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Luz Roncal (Basque Center for Applied Mathematics)
DTSTART:20221122T070000Z
DTEND:20221122T080000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/12
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/12/">Unique continuation for fractional discrete ell
 iptic equations</a>\nby Luz Roncal (Basque Center for Applied Mathematics)
  as part of Nonlinear Analysis Seminar Series\n\nLecture held in Room M210
  in NTNU Gongguan Campus Mathematics Building.\n\nAbstract\nIn this talk w
 e will describe several qualitative and quantitative unique continuation p
 roperties for the fractional discrete Laplacian. We will show that\, in co
 ntrast to the fractional continuous Laplacian\, global unique continuation
  fails to hold in general for fractional discrete elliptic equations.\n\nW
 e will also discuss quantitative versions of unique continuation which ill
 ustrate how the properties in the continuous setting may be recovered if e
 xponentially small (in terms of the lattice size) correction factors are a
 dded.\n\nJoint work with Aingeru Fernández-Bertolin and Angkana Rüland.\
 n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/12/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Serena Dipierro (University of Western Australia)
DTSTART:20230411T070000Z
DTEND:20230411T080000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/13
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/13/">The Bernstein technique for integro-differentia
 l equations</a>\nby Serena Dipierro (University of Western Australia) as p
 art of Nonlinear Analysis Seminar Series\n\nLecture held in Room M210 in N
 TNU Gongguan Campus Mathematics Building.\n\nAbstract\nIn this talk we dis
 cuss how to extend the classical Bernstein technique to the setting of int
 egro-differential operators. As a consequence of this\, we are able to pro
 vide first and one-sided second derivative estimates for solutions to frac
 tional equations. Our method is robust enough to be applied to some Pucci-
 type extremal equations and to obstacle problems for fractional operators.
 \n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/13/
END:VEVENT
BEGIN:VEVENT
SUMMARY:María J. Carro (Universidad Complutense de Madrid)
DTSTART:20230418T070000Z
DTEND:20230418T080000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/14
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/14/">Solving the Dirichlet and the Neumann problem a
 t the end-point</a>\nby María J. Carro (Universidad Complutense de Madrid
 ) as part of Nonlinear Analysis Seminar Series\n\nLecture held in Room M21
 0 in NTNU Gongguan Campus Mathematics Building.\n\nAbstract\nIn 1980 C. Ke
 nig proved that for every Lipschitz domain $\\Omega$ in the plane there ex
 ists $1\\le p_0<2$ so that the Dirichlet problem has a solution for every 
 $f\\in L^p(ds)$ and every $p\\in (p_0\, \\infty)$. Moreover\, if $p_0>1$\,
  the result is false for $p\\le p_0$. The goal of this talk is to analyze 
 what happen at the endpoint $p_0$\; that is\, we want to look for spaces $
 X\\subset L^{p_0}$  so that the Dirichlet problem has a solution for every
  $f\\in X$. These spaces $X$ will be either a Lorentz space $L^{p_0\,1} (d
 s)$ or some Orlicz space of logarithmic type. Similar results will be pres
 ented for the Neumann problem. This is a joint work with Virginia Naibo an
 d Carmen Ortiz-Caraballo.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/14/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Daniel Campbell (Charles University)
DTSTART:20230307T070000Z
DTEND:20230307T080000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/15
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/15/">Injectivity in second-gradient Nonlinear Elasti
 city</a>\nby Daniel Campbell (Charles University) as part of Nonlinear Ana
 lysis Seminar Series\n\nLecture held in Room M210 in NTNU Gongguan Campus 
 Mathematics Building.\n\nAbstract\nWe study injectivity for models of Nonl
 inear Elasticity that involve the second gradient. We assume that $\\Omega
 \\subset\\mathbb{R}^n$ is a domain\, $f\\in W^{2\,q}(\\Omega\,\\mathbb{R}^
 n)$ satisfies $|J_f|^{-a}\\in L^1$ and that $f$ equals a given homeomorphi
 sm on $\\partial \\Omega$. Under suitable conditions on $q$ and $a$ we sho
 w that $f$ must be a homeomorphism. As a main new tool we find an optimal 
 condition for $a$ and $q$ that imply that $\\mathcal{H}^{n-1}(\\{J_f=0\\})
 =0$ and hence $J_f$ cannot change sign. We further specify in dependence o
 f $q$ and $a$ the maximal Hausdorff dimension $d$ of the critical set $\\{
 J_f=0\\}$. The sharpness of our conditions for $d$ is demonstrated by cons
 tructing respective counterexamples.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/15/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Keng Hao Ooi (National Central University)
DTSTART:20230314T070000Z
DTEND:20230314T080000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/16
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/16/">Harmonic Analysis in Nonlinear Potential Theory
 </a>\nby Keng Hao Ooi (National Central University) as part of Nonlinear A
 nalysis Seminar Series\n\nLecture held in Room M210 in NTNU Gongguan Campu
 s Mathematics Building.\n\nAbstract\nIn this talk I will introduce a type 
 of Sobolev multiplier which appears naturally in many super critical nonli
 near PDEs.  We will briefly study the preduals of the Sobolev multplier sp
 aces and the boundedness of Hardy-Littlewood maximal operators on such spa
 ces.  Furthermore\, the boundedness of maximal operators on the spaces of 
 Choquet integrals associated with capacities will also be addressed.  The 
 main tools in tackling these problems rely on classical harmonic analysis 
 and nonlinear potential theory.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/16/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Dominic Breit (TU Clausthal)
DTSTART:20230328T070000Z
DTEND:20230328T080000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/17
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/17/">Inclusion relations among fractional Orlicz-Sob
 olev spaces and a Littlewood-Paley characterization</a>\nby Dominic Breit 
 (TU Clausthal) as part of Nonlinear Analysis Seminar Series\n\nLecture hel
 d in Room M210 in NTNU Gongguan Campus Mathematics Building.\n\nAbstract\n
 Optimal embeddings among fractional Orlicz-Sobolev spaces with different s
 moothness are characterized. The equivalence of their Gagliardo-Slobodecki
 j norms to norms defined via Littlewood-Paley decompostions\, via oscillat
 ions\, or via Besov type difference quotients is also established. These e
 quivalences\, of independent interest\, are a key tool in the proof of the
  relevant embeddings. \nThis is joint work with Andrea Cianchi\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/17/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Abhishek Ghosh (TIFR Centre For Applicable Mathematics)
DTSTART:20230425T070000Z
DTEND:20230425T080000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/18
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/18/">On bilinear Stein-Weiss inequality</a>\nby Abhi
 shek Ghosh (TIFR Centre For Applicable Mathematics) as part of Nonlinear A
 nalysis Seminar Series\n\nLecture held in Room M210 in NTNU Gongguan Campu
 s Mathematics Building.\n\nAbstract\nIn this talk\, we discuss some biline
 ar fractional integral operators introduced by Kenig and Stein. Also\, the
  Stein-Weiss inequality and its bilinear analogues will be addressed in Eu
 clidean space and beyond. This is a joint work with Rajesh K. Singh.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/18/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Catalin Carstea (National Yang Ming Chiao Tung University)
DTSTART:20230321T070000Z
DTEND:20230321T080000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/19
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/19/">An inverse problem for the porous medium equati
 on</a>\nby Catalin Carstea (National Yang Ming Chiao Tung University) as p
 art of Nonlinear Analysis Seminar Series\n\nLecture held in Room M210 in N
 TNU Gongguan Campus Mathematics Building.\n\nAbstract\nThe porous medium e
 quation is a degenerate parabolic type quasilinear equation that models\, 
 for example\, the flow of a gas through a porous medium. In this talk I wi
 ll present recent results on uniqueness in  the inverse boundary value pro
 blem for this equation. These are the first such results to be obtained fo
 r a degenerate parabolic equation. The talk is based on work with T. Ghosh
  & G. Nakamura and T. Ghosh & G. Uhlmann.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/19/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Anna Kh. Balci (Universität Bielefeld)
DTSTART:20230516T070000Z
DTEND:20230516T080000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/20
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/20/">Behind the regularity: variational problems wit
 h energy gaps</a>\nby Anna Kh. Balci (Universität Bielefeld) as part of N
 onlinear Analysis Seminar Series\n\nLecture held in Room M210 in NTNU Gong
 guan Campus Mathematics Building.\n\nAbstract\nWe study different  problem
 s with energy gaps: local and nonlocal double potential\, variable exponen
 t and weights models. We design the general procedure to construct new exa
 mples of energy gaps  and present the numerical scheme that converges to t
 he global minimiser of the problem.  The talk is based on several joint pr
 ojects with Lars Diening\, Michail Surnachev\, Johanness Srorn and Christo
 ph Ortner.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/20/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Qing Han (Notre Dame)
DTSTART:20230607T060000Z
DTEND:20230607T070000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/21
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/21/">A Concise Boundary Regularity for the Uniformly
  Degenerate Elliptic Equations</a>\nby Qing Han (Notre Dame) as part of No
 nlinear Analysis Seminar Series\n\nLecture held in Room M210 in NTNU Gongg
 uan Campus Mathematics Building.\n\nAbstract\nUniformly degenerate ellipti
 c equations appear frequently in many geometric problems. Solutions may ex
 hibit singular behaviors near the boundary where the degeneracy occurs. Us
 ually\, behaviors of solutions near the boundary are described through exp
 ansions. In this talk\, we identify a precise singular term as an addition
 al independent self-variable and establish a concise boundary regularity.\
 n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/21/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Tien Nguyen (National Taiwan University)
DTSTART:20230912T070000Z
DTEND:20230912T080000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/22
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/22/">Singularities in the Keller-Segel system</a>\nb
 y Tien Nguyen (National Taiwan University) as part of Nonlinear Analysis S
 eminar Series\n\nLecture held in Room M210 in NTNU Gongguan Campus Mathema
 tics Building.\n\nAbstract\nThe talk presents constructions of blowup solu
 tions to the Keller-Segel system in $\\mathbb{R}^d$.\n\n\n$d = 2$ ($L^1$-c
 ritical): There exist finite time single blowup solutions that are of Type
  II with finite mass. Blowup rates are quantized according to a discrete s
 pectrum of a linearized operator around the rescaled stationary solution i
 n the self-similar setting. There is also \\textit{multiple collapsing blo
 wup solutions} formed by a collision of multiple single solutions with sel
 f-similarity that provides a brand new mechanism of singularity formation.
 \n\n\n$d \\geq 3$ ($L^1$-supercritical): For $d \\geq 3$\, there exist fin
 ite time blowup solutions having the form of collapsing-ring which consist
 s of an imploding\, smoothed-out shock wave moving towards the origin to f
 orm a Dirac mass at the singularity. For $d = 3\,4 $\, we found blowup sol
 utions with infinite mass that are asymptotically self-similar with a log 
 correction to their profile. \n\n\nThe constructions rely on a spectral ap
 proach for multiple-scale problems\, renormalization technique\, and refin
 ed energy estimates. The talk is based on a series of joint works with C. 
 Collot (Paris Cergy)\, T. Ghoul (NYU Abu Dhabi)\, N. Nouaili (Paris Dauphi
 ne)\, N. Masmoudi (NYU) and H. Zaag (Paris Nord).\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/22/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Andrea Cianchi (Universita' di Firenze)
DTSTART:20231003T070000Z
DTEND:20231003T080000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/24
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/24/">Local boundedness of minimizers under unbalance
 d Orlicz growth conditions</a>\nby Andrea Cianchi (Universita' di Firenze)
  as part of Nonlinear Analysis Seminar Series\n\nLecture held in Room M210
  in NTNU Gongguan Campus Mathematics Building.\n\nAbstract\nLocal minimize
 rs of integral functionals of the calculus of variations are analyzed unde
 r growth conditions dictated by different lower and upper bounds for the i
 ntegrand.  Growths \n of non-necessarily power-type are allowed. The local
  boundedness of the relevant minimizers is established under a suitable ba
 lance between the lower and the upper bounds. Classical minimizers\, as we
 ll as quasi-minimizers are included in our discussion. Functionals subject
  to so-called $p\,q$-growth conditions are embraced as special cases and t
 he corresponding sharp results available in the literature are recovered.\
 n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/24/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Juan Manfredi (University of Pittsburgh)
DTSTART:20231017T010000Z
DTEND:20231017T020000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/25
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/25/">On Viscosity Solutions to the Non-Homogeneous I
 nfinite Laplace Equation</a>\nby Juan Manfredi (University of Pittsburgh) 
 as part of Nonlinear Analysis Seminar Series\n\nLecture held in Room M210 
 in NTNU Gongguan Campus Mathematics Building.\n\nAbstract\nWe will revisit
  the Theorem on Sums and  use it to study viscosity solutions of non-homog
 eneous equations involving the infinite Laplacian in Euclidean Space\, Rie
 mannian manifolds\, and Carnot Groups.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/25/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Zdeněk Mihula (Czech Technical University in Prague)
DTSTART:20230919T070000Z
DTEND:20230919T080000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/26
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/26/">Optimal Sobolev inequalities in the hyperbolic 
 space</a>\nby Zdeněk Mihula (Czech Technical University in Prague) as par
 t of Nonlinear Analysis Seminar Series\n\nLecture held in Room M210 in NTN
 U Gongguan Campus Mathematics Building.\n\nAbstract\nIn this talk\, we con
 sider a (higher order) Sobolev inequality for the Laplace--Beltrami operat
 or in the ball model of the hyperbolic space $\\mathbb{H}^n$\, and we look
  for function spaces that are in a sense optimal in the inequality. The in
 equality in question is\n$$\\|u\\|_{Y(\\mathbb{H}^n)} \\leq C \\|\\nabla_g
 ^m u\\|_{X(\\mathbb{H}^n)} \\quad \\text{for every $u\\in V_0^m X(\\mathbb
 {H}^n)$}\;$$\nhere $$\\nabla_g^m = \n\\begin{cases}\n\\Delta_g^{\\frac{m}{
 2}} \\quad &\\text{if $m$ is even}\,\\\\\n\\nabla_g\\Delta_g^{\\lfloor \\f
 rac{m}{2} \\rfloor} \\quad &\\text{if $m$ is odd}\,\n\\end{cases}\n$$\nwhe
 re $\\Delta_g$ is the Laplace--Beltrami operator and $\\nabla_g$ is the hy
 perbolic gradient\; $X(\\mathbb{H}^n)$ and $Y(\\mathbb{H}^n)$ are rearrang
 ement-invariant spaces\, and $V_0^m X(\\mathbb{H}^n)$ is a suitable $m$th 
 order Sobolev space. For a given rearrangement-invariant space $X(\\mathbb
 {H}^n)$\, we will describe the optimal (i.e.\, with the strongest norm) re
 arrangement-invariant space $Y(\\mathbb{H}^n)$ on the left-hand side.\n\nW
 e first discuss the general description(s) of the optimal space. Then we t
 urn our attention to some concrete examples. Namely\, when $X$ is $L^1$\, 
 $L^\\frac{n}{m}$\, or an exponential Orlicz space ``near $L^\\infty$''. Ev
 en in these simple cases\, the inequalities that we obtain seems to be mis
 sing in the literature (especially\, when $m\\geq3$).\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/26/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Rami Ayoush (Universitreiy of Warsaw)
DTSTART:20231128T070000Z
DTEND:20231128T080000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/27
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/27/">On finite configurations in the spectra of sing
 ular measures</a>\nby Rami Ayoush (Universitreiy of Warsaw) as part of Non
 linear Analysis Seminar Series\n\nLecture held in Room M210 in NTNU Gonggu
 an Campus Mathematics Building.\n\nAbstract\nDuring the talk I will discus
 s applications of elementary additive combinatorics to dimensional estimat
 es of PDE- and Fourier-constrained measures. My main tool will be a simple
  certainty principle of the following form: a set $S ⊂ \\mathbb{R}^N$ co
 ntains a given finite linear pattern if $S$ is a spectrum of a sufficientl
 y singular measure.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/27/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Cody Stockdale (Clemson University)
DTSTART:20230926T010000Z
DTEND:20230926T020000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/28
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/28/">A different approach to endpoint weak-type esti
 mates for Calderón-Zygmund operators</a>\nby Cody Stockdale (Clemson Univ
 ersity) as part of Nonlinear Analysis Seminar Series\n\nLecture held in Ro
 om M210 in NTNU Gongguan Campus Mathematics Building.\n\nAbstract\nThe wea
 k-type $(1\,1)$ estimate for Calderón-Zygmund operators is fundamental in
  harmonic analysis. We investigate weak-type inequalities for Calderón-Zy
 gmund singular integral operators using the Calderón-Zygmund decompositio
 n and ideas inspired by Nazarov\, Treil\, and Volberg. We discuss applicat
 ions of these techniques in the Euclidean setting\, in weighted settings\,
  for multilinear operators\, for operators with weakened smoothness assump
 tions\, and in studying the dimensional dependence of the Riesz transforms
 .\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/28/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Armin Schikorra (University of Pittsburgh)
DTSTART:20231114T010000Z
DTEND:20231114T020000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/29
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/29/">On s-Stability of W^{s\,n/s}-minimizing maps be
 tween spheres in homotopy classes</a>\nby Armin Schikorra (University of P
 ittsburgh) as part of Nonlinear Analysis Seminar Series\n\nLecture held in
  Room M210 in NTNU Gongguan Campus Mathematics Building.\n\nAbstract\nWe c
 onsider maps between spheres S^n to S^\\ell that minimize the\nSobolev-spa
 ce energy W^{s\,n/s} for some s \\in (0\,1) in given homotopy\nclass.\nThe
  basic question is: in which homotopy class does a minimizer exist?\nThis 
 is a nontrivial question since the energy under consideration is\nconforma
 lly invariant and bubbles can form.\nSacks-Uhlenbeck theory tells us that 
 minimizers exist in a set of\nhomotopy classes that generates the whole ho
 motopy group\n\\pi_{n}(\\S^\\ell). In some situations explicit examples ar
 e known if\nn/s = 2 or s=1.\n\nIn our talk we are interested in the stabil
 ity of the above question\nin dependence of s. We can show that as s varie
 s locally\, the set of\nhomotopy classes in which minimizers exists can be
  chosen stable. We\nalso discuss that the minimum W^{s\,n/s}-energy in hom
 otopy classes is\ncontinuously depending on s.\n\nJoint work with K. Mazow
 iecka (U Warsaw)\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/29/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Felipe Hernandez (MIT)
DTSTART:20231024T010000Z
DTEND:20231024T020000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/30
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/30/">Uncertainty principles for Wigner functions</a>
 \nby Felipe Hernandez (MIT) as part of Nonlinear Analysis Seminar Series\n
 \nLecture held in Room M210 in NTNU Gongguan Campus Mathematics Building.\
 n\nAbstract\nThe Wigner function of a quantum state is a way of describing
  the phase space distribution of a quantum particle.  The uncertainty prin
 ciple from Fourier analysis places some restriction on the allowable decay
  of a Wigner function.  In this talk I will give an introduction to the Wi
 gner function and show that rapidly decaying Wigner functions must also be
  Schwartz\, which can also be interpreted as a type of uncertainty princip
 le.  This is based on joint work with Jess Riedel.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/30/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Angela Alberico (CNR - IAC)
DTSTART:20231121T070000Z
DTEND:20231121T080000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/31
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/31/">Optimal embeddings for fractional Orlicz-Sobole
 v spaces</a>\nby Angela Alberico (CNR - IAC) as part of Nonlinear Analysis
  Seminar Series\n\nLecture held in Room M210 in NTNU Gongguan Campus Mathe
 matics Building.\n\nAbstract\nThe optimal target space is exhibited for em
 beddings of fractional-order Orlicz-Sobolev spaces.\nBoth the subcritical 
 and the supercritical regimes are considered.\nIn the former case\, the sm
 allest possible Orlicz target space is detected. In the latter\,\n the rel
 evant Orlicz-Sobolev spaces are shown to be embedded into the space of bou
 nded\ncontinuous functions in $\\mathbb R^n$. Moreover\, their\n optimal m
 odulus of continuity is exhibited.\nThese results are the subject of a ser
 ies of joint papers with Andrea Cianchi\, Lubos Pick and Lenka\nSlavikova.
 \n\n\nA.Alberico\,  A.Cianchi\, L.Pick and L.Slavikova\,\nFractional Orlic
 z-Sobolev embeddings\,\n             J. de Mathematiqués Pures  et Appliq
 uées\, 149 (2021).\n\n\nA.Alberico\,  A.Cianchi\, L.Pick and L.Slavikova\
 ,\n             Boundedness of functions in fractional Orlicz-Sobolev spac
 es\,\n             Nonlinear Analysis\, 230 (2023).\n\n\n A.Alberico\,  A.
 Cianchi\, L.Pick and L.Slavikova\,\nOn the Modulus of Continuity of fracti
 onal Orlicz-Sobolev functions\,\n              in progress.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/31/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Piotr Hajłasz (University of Pittsburgh)
DTSTART:20231205T010000Z
DTEND:20231205T020000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/32
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/32/">Approximation of mappings with derivatives of l
 ow rank</a>\nby Piotr Hajłasz (University of Pittsburgh) as part of Nonli
 near Analysis Seminar Series\n\nLecture held in Room M210 in NTNU Gongguan
  Campus Mathematics Building.\n\nAbstract\nMy talk is based on two recent 
 joint papers with Paweł Goldstein.\n\n\nJacek Gałęski in 2017\, in the 
 context of his research in geometric measure theory\, formulated the follo
 wing conjecture:\n\nConjecture.\nLet $1\\leq m< n$ be integers and let $\\
 Omega\\subset\\mathbb{R}^n$ be open. If $f\\in C^1(\\Omega\,\\mathbb{R}^n)
 $ satisfies $\\operatorname{rank} Df\\leq m$ everywhere in $\\Omega$\, the
 n $f$ can be uniformly approximated by smooth mappings $g\\in C^\\infty(\\
 Omega\,\\mathbb{R}^n)$ such that $\\operatorname{rank} Dg\\leq m$ everywhe
 re in $\\Omega$.\n\nOne can also modify the conjecture and ask about a loc
 al approximation: smooth approximation in a neighborhood of any point.\nTh
 ese are very natural problems with possible applications to PDEs and Calcu
 lus of Variations. However\, the problems are difficult\, because standard
  approximation techniques like the one based on convolution do not preserv
 e the rank of the derivative. It is a highly nonlinear constraint\, diffic
 ult to deal with.\n\nIn 2018 Goldstein and Hajłasz obtained infinitely ma
 ny counterexamples to this conjecture. Here is one:\n\nExample.\nThere is 
 $f\\in C^1(\\mathbb{R}^5\,\\mathbb{R}^5)$ with $\\operatorname{rank} Df\\l
 eq 3$ that cannot be locally and uniformly approximated by mappings\n$g\\i
 n C^2(\\mathbb{R}^5\,\\mathbb{R}^5)$ satisfying $\\operatorname{rank} Dg\\
 leq 3$.\n\nThis example is a special case of a much more general result an
 d the construction heavily depends on algebraic topology including the hom
 otopy groups of spheres and the Freudenthal suspension theorem.\n\nMore re
 cently Goldstein and Hajłasz proved the conjecture in the positive in the
  case when $m=1$. The proof is based this time on methods of analysis on m
 etric spaces and in particular on factorization of a mapping through metri
 c trees.\n\nThe method of factorization through metric trees used in the p
 roof of the conjecture when $m=1$ is very different and completely unrelat
 ed to the methods of algebraic topology used in the construction of counte
 rexamples. However\, quite surprisingly\, both techniques have originally 
 been used by Wenger and Young as tools for study of Lipschitz homotopy gro
 ups of the Heisenberg group\, a problem that seems completely unrelated to
  problems discussed in this talk.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/32/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Bogdan Raita (Georgetown University)
DTSTART:20231107T010000Z
DTEND:20231107T020000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/33
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/33/">Limiting linear $L^1$ estimates near the bounda
 ry</a>\nby Bogdan Raita (Georgetown University) as part of Nonlinear Analy
 sis Seminar Series\n\nLecture held in Room M210 in NTNU Gongguan Campus Ma
 thematics Building.\n\nAbstract\nWe identify necessary and sufficient cond
 itions on $k$th order linear differential operators $\\mathbb{A}$ in terms
  of a fixed halfspace $H\\subset\\mathbb{R}^n$ such that the Gagliardo--Ni
 renberg--Sobolev inequality\n		$$\n		\\|D^{k-1}u\\|_{\\mathrm{L}^{\\frac{n
 }{n-1}}(H)}\\leq c\\|\\mathbb{A} u\\|_{\\mathrm{L}^1(H)}\\quad\\text{for }
 u\\in\\mathrm{C}^\\infty_c (\\mathbb{R}^{n}\,V)\n		$$\n		holds. This comes
  as a consequence of sharp trace theorems on $\\partial H$. Strong estimat
 es on lower order derivatives are the best possible due to the failure of 
 Calder\\'on--Zygmund theory in $L^1$.\n\nJoint work with Franz Gmeineder a
 nd Jean Van Schaftingen.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/33/
END:VEVENT
BEGIN:VEVENT
SUMMARY:David Cruz-Uribe (University of Alabama)
DTSTART:20231212T070000Z
DTEND:20231212T080000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/34
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/34/">Weighted norm inequalities for multiplier weak-
 type inequalities</a>\nby David Cruz-Uribe (University of Alabama) as part
  of Nonlinear Analysis Seminar Series\n\nLecture held in Room M210 in NTNU
  Gongguan Campus Mathematics Building.\n\nAbstract\nIn this talk we will c
 onsider a version of weak-type inequalities we\nrefer to as {\\em multipli
 er weak-type inequalities}.  Given a weight\n$w$ and $1\\leq p<\\infty$\, 
  the $(p\,p)$ multiplier weak-type inequality\nfor an operator $T$ is of t
 he form\n\\[ |\\{ x\\in {\\mathbb{R}^n} : |w^{\\frac{1}{p}}(x)T(w^{-\\frac
 {1}{p}}f)(x)|> t\\}|\n  \\leq \\frac{C}{t^p} \\int_{\\mathbb{R}^n} |f(x)|^
 p\\\,dx.  \\]\nThese inequalities follow from the a strong $(p\,p)$ inequa
 lity of the\nform\n\\[ \\int_{\\mathbb{R}^n} |Tf(x)|^pw(x)\\\,dx \\leq C \
 \int_{\\mathbb{R}^n} |f(x)|^pw(x)\\\,dx \\]\nby mapping $f\\mapsto w^{-\\f
 rac{1}{p}}f$ and applying Chebyshev's\ninequality.  These inequalities wer
 e first considered by Muckenhoupt\nand Wheeden (1977) for the maximal oper
 ator and the Hilbert transform\non the real line.  They showed that such i
 nequalities hold if $w$ is a\nMuckenhoupt $A_p$ weight\, but gave examples
  to show that the class of\nweights is strictly larger for these operators
 .  Their $A_p$ results\nwere extended to all dimensions and all Calder\\'o
 n-Zygmund integral\noperators by myself\, Martell\, and Perez (2005).  The
 y have attracted\nrenewed attention since they were shown to be the right 
 way of\ngeneralizing weak-type inequalities to the setting of matrix weigh
 ts\n(DCU\, Isralowitz\, Moen\, Pott\, Rivera-Rios\, 2020).\n\nIn this talk
 \, we will consider the problem of quantitative estimates\,\nin terms of t
 he $A_p$ characteristic\, for maximal operators and\nsingular integrals.  
 Our results extend those gotten in 2020 in the\ncase $p=1$ to all $1\\leq 
 p<\\infty$.   We also show that our proofs can\nbe adapted to prove quanti
 tative estimates for matrix weighted\ninequalities.  Finally\, we prove th
 e analogous results for the\nfractional integral/Riesz potential in both t
 he scalar and matrix\nweighted cases.  These results are completely new\, 
 as even qualitative\nresults for fractional integrals were not known.\n\n\
 \bigskip\n\nThis talk is joint work with Brandon Sweeting\, the University
  of Alabama.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/34/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Dr. Anastasia Molchanova (University of Vienna)
DTSTART:20240319T070000Z
DTEND:20240319T080000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/35
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/35/">Limits of Sobolev Homeomorphisms in Nonlinear E
 lasticity</a>\nby Dr. Anastasia Molchanova (University of Vienna) as part 
 of Nonlinear Analysis Seminar Series\n\nLecture held in Room 509\, Cosmolo
 gy Building\, National Taiwan University.\n\nAbstract\nLimits of Sobolev h
 omeomorphisms naturally appear in geometric function theory\, calculus of 
 variations\, and continuum mechanics. In this talk\, we discuss essential 
 properties of mappings essential for elastic deformations\, focusing on as
 pects such as continuity\, injectivity\, and differentiability\, as well a
 s Lusin's $(N)$- and $(N^{-1})$-conditions.\nWe consider variational probl
 ems of nonlinear elasticity\, where admissible deformations are given by l
 imits of Sobolev homeomorphisms\, and prove the existence of minimizers.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/35/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Dr. MingQing Xiao (Southern Illinois University)
DTSTART:20240312T010000Z
DTEND:20240312T020000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/36
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/36/">Low Rank Approximation of Multi-Dimensional Dat
 a Set for Completion</a>\nby Dr. MingQing Xiao (Southern Illinois Universi
 ty) as part of Nonlinear Analysis Seminar Series\n\nLecture held in Room M
 212 in NTNU Gongguan Campus Mathematics Building.\n\nAbstract\nLarge datas
 ets often manifest naturally as multi-dimensional arrays\, commonly referr
 ed to as tensors. These tensors may represent diverse phenomena\, from sen
 sor measurements in scientific experiments to user behavior in recommendat
 ion systems. However\, real-world data is rarely perfect\, and incomplete 
 entries are common due to various reasons such as sensor failures\, missin
 g observations\, or privacy constraints. In this talk\, we introduce a new
  nonconvex regularization approach\, which can better capture the low-rank
  characteristics than the convex approach for data completion. A minimizat
 ion algorithm\, associated with the augmented Lagrangian multipliers and t
 he nonconvex regularizer\, will be presented.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/36/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Dr. Fulton Gonzalez (Tufts University)
DTSTART:20240326T073000Z
DTEND:20240326T083000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/37
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/37/">The Snapshot Problem for the Wave Equation</a>\
 nby Dr. Fulton Gonzalez (Tufts University) as part of Nonlinear Analysis S
 eminar Series\n\nLecture held in Room M210 in NTNU Gongguan Campus Mathema
 tics Building.\n\nAbstract\nBy definition\, a wave is a $C^\\infty$ soluti
 on $u(x\,t)$ of the wave equation on $\\mathbb{R}^n$\, and a snapshot of t
 he wave $u$ at time $t$  is the function $u_t$ on $\\mathbb{R}^n$ given by
  $u_t(x)=u(x\,t)$.  We show that there are infinitely many waves with give
 n $C^\\infty$ snapshots $f_0$ and $f_1$ at times $t=0$ and $t=1$ respectiv
 ely\, but that all such waves have the same snapshots at integer times.  W
 e present necessary and sufficient conditions for the existence and unique
 ness of a wave $u$ to have three given snapshots at three different times\
 , and we show how this leads to problems in Diophantine approximations and
  "small denominators"\, which dates back to the early study of the $n$-bod
 y problem in $\\mathbb{R}^3$. We consider generalizations to the Euler-Poi
 sson-Darboux equation and to modified wave equations on spheres and symmet
 ric spaces\, as well as some open questions. \n\n \nJoint with J. Christen
 sen (Colgate)\, J. Wang (N. China Inst. of Science & Technology)\, and T. 
 Kakehi (Tsukuba).\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/37/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Dr. Oscar Dominguez Bonilla (Cunef Universidad)
DTSTART:20240402T070000Z
DTEND:20240402T080000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/38
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/38/">Affine fractional Moser-Trudinger and Morrey in
 equalities</a>\nby Dr. Oscar Dominguez Bonilla (Cunef Universidad) as part
  of Nonlinear Analysis Seminar Series\n\nLecture held in Room 509\, Cosmol
 ogy Building\, National Taiwan University.\n\nAbstract\nIn this talk we es
 tablish affine versions of fractional Moser-Trudinger and Morrey inequalit
 ies. These new inequalities are stronger than the affine Moser-Trudinger a
 nd Morrey inequalities due to Cianchi-Lutwak-Yang-Zhang and complement the
  affine fractional Sobolev inequalities of Haddad-Ludwig. This is a joint 
 work with Y. Li\, S. Tikhonov\, D. Yang\, and W. Yuan.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/38/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Dr. Prasun Roychowdhury (National Center for Theoretical Sciences 
 Taiwan)
DTSTART:20240416T070000Z
DTEND:20240416T080000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/40
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/40/">Classification of radial solutions to $-\\Delta
 _g u = e^u$ on Riemannian models</a>\nby Dr. Prasun Roychowdhury (National
  Center for Theoretical Sciences Taiwan) as part of Nonlinear Analysis Sem
 inar Series\n\nLecture held in Room M210 in NTNU Gongguan Campus Mathemati
 cs Building.\n\nAbstract\nThe talk is devoted to the complete classificati
 on with respect to asymptotic behaviour\, stability\, and intersections pr
 operties of radial smooth solutions to the equation $-\\Delta_g u=e^u$ on 
 Riemannian model manifolds $(M\,g)$ in dimension $N\\ge 2$. Our assumption
 s include Riemannian manifolds with sectional curvatures bounded or unboun
 ded from below. Intersection and stability properties of radial solutions 
 are influenced by the dimension $N$ in the sense that two different kinds 
 of behaviour occur when $2\\le N\\le 9$ or $N\\ge 10$\, respectively. The 
 crucial role of these dimensions in classifying solutions is well-known in
  Euclidean space\; here the analysis highlights new properties of solution
 s that cannot be observed in the flat case. This is based on a joint work 
 with Elvise Berchio\, Alberto Ferrero\, and Debdip Ganguly.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/40/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Dr. Robin Neumayer (Carnegie Mellon University)
DTSTART:20240611T010000Z
DTEND:20240611T020000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/41
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/41/">The Saint-Venant inequality and quantitative re
 solvent estimates for the Dirichlet Laplacian</a>\nby Dr. Robin Neumayer (
 Carnegie Mellon University) as part of Nonlinear Analysis Seminar Series\n
 \nLecture held in Room M210 in NTNU Gongguan Campus Mathematics Building.\
 n\nAbstract\nAmong all cylindrical beams of a given cross-sectional area\,
  those with circular cross sections are the most resistant to twisting for
 ces. The general dimensional analogue of this fact is the Saint-Venant ine
 quality\, which says that balls have the largest torsional rigidity among 
 subsets of Euclidean space with a fixed volume. We discuss recent results 
 showing that for a given set $E$\, the gap in the Saint-Venant inequality 
 quantitatively controls the $L^2$ difference between solutions of the Pois
 son equation on $E$ and on the nearest ball\, for any Holder continuous ri
 ght-hand side. We additionally prove quantitative closeness of all eigenfu
 nctions of the Dirichlet Laplacian. This talk is based on joint work with 
 Mark Allen and Dennis Kriventsov.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/41/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Dr. Cody Stockdale (Clemson University)
DTSTART:20240528T070000Z
DTEND:20240528T080000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/42
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/42/">On the theory of compact Calderón-Zygmund oper
 ators</a>\nby Dr. Cody Stockdale (Clemson University) as part of Nonlinear
  Analysis Seminar Series\n\nLecture held in Room M210 in NTNU Gongguan Cam
 pus Mathematics Building.\n\nAbstract\nWe present new developments in the 
 theory of compact Calderón-Zygmund operators. In particular\, we give a n
 ew formulation of the $T1$ theorem for compactness of CZ operators\, which
 \, compared to existing compactness criteria\, more closely resembles Davi
 d and Journé’s classical $T1$ theorem for boundedness and follows from 
 a simpler argument. Our methods generalize to treat a class of "localized"
  operators on a Hilbert space -- we apply this abstraction to characterize
  the compact pseudodifferential operators on $L^2(\\mathbb{R}^n)$. Additio
 nally\, we discuss the extension of compact CZ theory to weighted Lebesgue
  spaces via sparse domination methods. \n\nThis talk is based on joint wor
 ks with Mishko Mitkovski\, Paco Villarroya\, Cody Waters\, and Brett Wick.
 \n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/42/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Prof. Ji Li (Macquarie University)
DTSTART:20240423T073000Z
DTEND:20240423T083000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/44
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/44/">Schatten Properties of Calderon–Zygmund Singu
 lar Integral Commutator on stratified Lie groups</a>\nby Prof. Ji Li (Macq
 uarie University) as part of Nonlinear Analysis Seminar Series\n\nLecture 
 held in Room 515 in NCTS in NTU.\n\nAbstract\nSchatten class estimates of 
 the commutator of Riesz transform in $\\mathbb R^n$ link to the quantised 
 derivative of A. Connes. A general setting for quantised calculus is a spe
 ctral triple $(\\mathcal A\,\\mathcal H\,D)$\, which consists of a Hilbert
  space $\\mathcal H$\, a pre-$C^*$-algebra $\\mathcal A $\, represented fa
 ithfully on $\\mathcal H$ and a self-adjoint operator $D$ acting on $\\mat
 hcal H$ such that every $a\\in A$ maps the domain of $D$ into itself and t
 he commutator $[D\,a] = Da-aD$ extends from the domain of $D$ to a bounded
  linear endomorphism of $\\mathcal H$. Here\, the quantised differential $
 \\qd a$ of $a \\in \\mathcal A$ is defined to be the bounded operator ${\\
 rm i} [{\\rm sgn}(D)\,a]$\, ${\\rm i}^2=-1$. \n\nWe provide full character
 isation of the Schatten properties of $[M_b\,T]$\,  the commutator of Cald
 er\\'{o}n--Zygmund singular integral $T$ with symbol $b$ $(M_bf(x):=b(x)f(
 x))$ on stratified Lie groups $\\mathcal G$. We show that\, when $p$ is la
 rger than the homogeneous dimension $\\mathbb Q$ of $\\mathcal G$\, the Sc
 hatten $\\mathcal L_p$ norm of the commutator is equivalent to the Besov s
 emi-norm $B_{p}^{\\mathbb Q/p}$ of the function $b$\; but when $p\\leq \\m
 athbb Q$\, the commutator belongs to $\\mathcal L_p$ if and only if $b$ is
  a constant. For the endpoint case at the critical index $p=\\mathbb Q$\, 
 we further show that the Schatten $\\mathcal L_{\\mathbb Q\,\\infty}$ norm
  of the commutator is equivalent to the Sobolev norm $\\dot{W}^{1\,\\mathb
 b Q}$ of $b$. Our method at the endpoint case differs from existing method
 s of Fourier transforms or trace formula for Euclidean spaces or Heisenber
 g groups\, respectively.\n\nThis talk is based on my recent work joint wit
 h Xiao Xiong and Fulin Yang.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/44/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Dr. You Wei-Chen (National Taiwan University)
DTSTART:20240430T070000Z
DTEND:20240430T080000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/45
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/45/">A self-improving property of Riesz potentials i
 n BMO</a>\nby Dr. You Wei-Chen (National Taiwan University) as part of Non
 linear Analysis Seminar Series\n\nLecture held in Room M210 in NTNU Gonggu
 an Campus Mathematics Building.\n\nAbstract\nIn this talk\, we introduce t
 he concept of beta-dimensional BMO space \\( BMO^\\beta \\) and the associ
 ated John-Nirenberg inequality. We will discuss the mapping properties of 
 Riesz potentials within \\(BMO^\\beta\\) spaces\, focusing specifically on
  the Morrey spaces and weak Lebesgue spaces \\(L^{n/ \\alpha\,\\infty} (\\
 mathbb{R}^n)\\).  Additionally\, we present that \\( I_\\alpha f \\in BMO^
 {n-\\alpha + \\epsilon} \\) is actually a necessary and sufficient conditi
 on for \\( I_\\alpha f \\in BMO \\) when \\( f \\) is a non-negative funct
 ion.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/45/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Dr. Bogdan Raita (Georgetown University)
DTSTART:20240618T073000Z
DTEND:20240618T083000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/46
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/46/">Self improving size estimates in compensated co
 mpactness</a>\nby Dr. Bogdan Raita (Georgetown University) as part of Nonl
 inear Analysis Seminar Series\n\nLecture held in Room 509\, Cosmology Buil
 ding\, National Taiwan University.\n\nAbstract\nWe review some recent resu
 lts in compensated compactness\, concerning primarily concentration effect
 s of pde constrained sequences. We show that Müller's $L\\log L$ bound \n
   $$\n    \\Phi(Du)\\geq 0\,\\\,Du\\in L^q(\\mathbb{R}^n)\\implies \\Phi(D
 u)\\in L\\log L_{loc}\n$$\n    for $\\Phi =\\det$ and $q=n$ holds for quas
 iconcave $\\Phi$ which are homogeneous of degree $q>1$. This contrasts sim
 ilar Hardy bounds which hold only for null Lagrangians.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/46/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Dr. José Carlos Bellido (Universidad de Castilla-La Mancha)
DTSTART:20240507T070000Z
DTEND:20240507T080000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/47
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/47/">Nonlocal gradients and applications to Continuu
 m Mechanics</a>\nby Dr. José Carlos Bellido (Universidad de Castilla-La M
 ancha) as part of Nonlinear Analysis Seminar Series\n\nLecture held in Roo
 m M210 in NTNU Gongguan Campus Mathematics Building.\n\nAbstract\nThis pre
 sentation collects joint work with C. Mora-Corral\, J. Cueto\, H. Schönbe
 rger\, P. Radu and M. Foss. \n\nInterest in nonlocal gradients has increas
 ed in the last decades due to development of nonlocal modeling in a variet
 y of fields\, including mechanics and materials science. We start by defin
 ing nonlocal gradients in a general context\, where their calculation depe
 nds on a general kernel. Our goal is to explore the structural properties 
 of spaces associated with these gradients. From a functional analysis pers
 pective\, we seek kernels that make these spaces useful for studying varia
 tional problems and\, consequently\, applicable to physical models. Beyond
  the theoretical groundwork\, we delve into the mathematical intricacies o
 f these new functional spaces. These spaces are essential for understandin
 g nonlocal phenomena and capturing behavior that local models might miss. 
 Nonlocal gradients find practical applications in solid mechanics\, partic
 ularly in finite elasticity. Additionally\, we establish connections betwe
 en  nonlocal models derived from nonlinearly elastic models and the well-k
 nown Eringen’s nonlocal model of linear elasticity. Remarkably\, these s
 olid mechanics models can be seen as a special case of state-based peridyn
 amics\, a continuum theory designed to address material failure where clas
 sical elasticity theories fall short.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/47/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Dr. Riju Basak (National Taiwan Normal University)
DTSTART:20240514T073000Z
DTEND:20240514T083000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/48
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/48/">Wave equation on Hardy spaces</a>\nby Dr. Riju 
 Basak (National Taiwan Normal University) as part of Nonlinear Analysis Se
 minar Series\n\nLecture held in Room 509\, Cosmology Building\, National T
 aiwan University.\n\nAbstract\nThe sharp fixed-time estimates for the solu
 tion of the Cauchy problem associated with the standard Euclidean Laplacia
 n on Lebesgue and Hardy spaces were first studied independently by A. Miya
 chi and J.C. Peral in 1980. However\, the sharp fixed-time estimate is sti
 ll not available for many operators\, especially on Hardy spaces for $0< p
  <1 $. \n\nIn this talk\, we shall discuss fixed-time estimates for the so
 lution of the wave equation associated with the twisted Laplacian. This ta
 lk is based on a joint work with K. Jotsaroop.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/48/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Prof. Diego Cordoba (ICMAT)
DTSTART:20241008T073000Z
DTEND:20241008T083000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/50
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/50/">Finite time blow-up for the hypodissipative Nav
 ier Stokes equations</a>\nby Prof. Diego Cordoba (ICMAT) as part of Nonlin
 ear Analysis Seminar Series\n\nLecture held in Room M210 in NTNU Gongguan 
 Campus Mathematics Building.\n\nAbstract\nIn this talk we establish the fo
 rmation of singularities of classical solutions with finite energy of the 
 forced fractional Navier Stokes equations where the dissipative term is gi
 ven by $|\\nabla|^{\\alpha}$ for any $\\alpha\\in [0\, \\alpha_0)$ ($\\alp
 ha_0 = 0.09\\cdots$).\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/50/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Prof. Yoshihiro Sawano (Chuo University)
DTSTART:20240910T010000Z
DTEND:20240910T020000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/51
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/51/">A norm close to the $L^1$-norm</a>\nby Prof. Yo
 shihiro Sawano (Chuo University) as part of Nonlinear Analysis Seminar Ser
 ies\n\nLecture held in Room M210 in NTNU Gongguan Campus Mathematics Build
 ing.\n\nAbstract\nAround 10 years ago\, Armin Schikorra\, Daniel Spector\,
  Jean Van Schaftingen pointed out that there exists a variant of the bound
 edness of the Riesz potential $I_\\alpha$ which maps $L^1$ to weak $L^{\\f
 rac{n}{n-\\alpha}}$. The goal of this talk is to extend it to Morrey space
 s. Some variants as well as the proof will be discussed. This is a joint w
 ork with Denny Ivanal Hakim and Mei Dita Kumala at Bandung Institute Techn
 ology.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/51/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Prof. Blake Temple (UC Davis)
DTSTART:20241015T010000Z
DTEND:20241015T020000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/52
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/52/">On the Essential Regularity of Singular Connect
 ions in Geometry</a>\nby Prof. Blake Temple (UC Davis) as part of Nonlinea
 r Analysis Seminar Series\n\nLecture held in Room M212 in NTNU Gongguan Ca
 mpus Mathematics Building.\n\nAbstract\nAuthor together with collaborator 
 Moritz Reintjes recently introduced the Regularity Transformation Equation
 s (RT-equations)\, an elliptic\, non-invariant system of equations which d
 etermine the Jacobians of coordinate transformations which (locally) lift 
 the regularity of a connection to one derivative above the regularity of i
 ts Riemann curvature tensor.   Our existence theory for the RT-equations g
 eneralize celebrated results of Kazden-DeTurck\, valid for Riemannian metr
 ics\, to arbitrary non-Riemannian connections\, including the metrics and 
 connections of General Relativity.   Authors have found applications of th
 e RT-equations\, including extending Uhlenbeck compactness from Riemannian
  to non-Riemannian connections on vector bundles\, extending existence and
  uniqueness of ODEs one derivative below the threshold for Picard's method
 \, and an application to the Strong Cosmic Censorship Conjecture (Reintjes
 ).   In this talk I discuss our forthcoming paper in which we use the theo
 ry of the RT-equations to give a necessary and sufficient condition for de
 termining when a singularity appearing in a connection or metric in geomet
 ry can be regularized by coordinate transformation\; we establish the cons
 istency of the $\\textit{essential}$\, highest possible regularity to whic
 h a singular connection can be regularized by coordinate transformation\; 
 and we describe an explicit procedure (based in the RT-equations) for cons
 tructing the coordinate transformations which lift a singular connection t
 o its essential regularity.  Results apply both locally and globally\, and
  we show that there always exists a maximal $C^\\infty$ atlas on a manifol
 d which globally preserves the essential regularity of any connection.  Ou
 r necessary and sufficient condition relies on our existence theory for th
 e RT-equations which we currently require connection regularity in $L^p$\,
  $p>n$\, sufficient to address shock wave singularities in GR\, but not ye
 t black hole singularities.  Extending our existence theory to the case $p
 \\verb+<+n$ is an important topic of authors' current research.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/52/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Prof. Simon Bortz (University of Alabama)
DTSTART:20241022T010000Z
DTEND:20241022T020000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/53
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/53/">Regularity of Co-normal Derivatives and Weights
 </a>\nby Prof. Simon Bortz (University of Alabama) as part of Nonlinear An
 alysis Seminar Series\n\nLecture held in Room M210 in NTNU Gongguan Campus
  Mathematics Building.\n\nAbstract\nThis talk is concerned with the proper
 ties of the co-normal derivative of (adjoint) solutions to elliptic and pa
 rabolic PDEs in divergence form\, that is\, $Lu = -div A \\nabla u = 0$ or
  $L = -\\partial_t u - div A \\nabla u = 0$ in some domain $\\Omega$. Spec
 ifically\,  the properties of co-normal derivative on a subset of the boun
 dary where the solution $u$ vanishes. A prototypical situation is when $\\
 Omega$ is the upper half space ($\\{(x\,\\lambda) : x \\in \\mathbb{R}^n\,
  \\lambda > 0\\}$ or $\\{(t\,x\,\\lambda) : t\\in \\mathbb{R}\, x \\in \\m
 athbb{R}^n\, \\lambda > 0\\}$) and $u$ is the Green function of $L$ with p
 ole at infinity and\, in that case\, the co-normal derivative is the ellip
 tic/parabolic measure. \n\nIn this talk\, I will introduce the co-normal d
 erivative and discuss some sufficient conditions on the coefficients $A$ f
 or the co-normal derivative to be quantitatively absolutely continuous wit
 h respect to surface measure or even have a density that is $\\dot{C}^\\al
 pha_{loc}$ (locally H\\"older continuous) on the boundary. The method will
  unify these regimes\, by refining the work of David\, Li and Mayboroda an
 d combining it with some of my recent work with Toro and Zhao\, and Egert 
 and Saari. For simplicity\, in the talk $\\Omega$ will be assumed to be th
 e upper half space\, but more exotic domains can be considered.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/53/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Dr. Reinaldo Resende (Carnegie Mellon University)
DTSTART:20241001T010000Z
DTEND:20241001T020000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/55
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/55/">Regularity results for area minimizing currents
 </a>\nby Dr. Reinaldo Resende (Carnegie Mellon University) as part of Nonl
 inear Analysis Seminar Series\n\nLecture held in Room M210 in NTNU Gonggua
 n Campus Mathematics Building.\n\nAbstract\nWe will explore exciting new r
 esults on the interior and boundary regularity of currents $T$ solving the
  oriented Plateau’s problem\, with a special focus on higher codimension
 s. We will extend well-known estimates concerning the Hausdorff dimension 
 of the interior singular set of $T$ to a broader context\, and also share 
 results from an upcoming work that optimally resolves several long-standin
 g open questions on boundary regularity. Additionally\, we’ll discuss re
 cent advancements in the rectifiability of the singular set and\, if time 
 permits\, review the general proof strategy for these regularity results u
 sing multivalued functions and the frequency function.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/55/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Prof. Willie Wong (Michigan State University)
DTSTART:20241126T010000Z
DTEND:20241126T020000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/56
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/56/">Some Big Bangs are Unstable</a>\nby Prof. Willi
 e Wong (Michigan State University) as part of Nonlinear Analysis Seminar S
 eries\n\nLecture held in Room M210 in NTNU Gongguan Campus Mathematics Bui
 lding.\n\nAbstract\nOur understanding of cosmological processes\, like man
 y other predictions of physical theories\, are based on studying regimes w
 here the equations of motion reduce to a finite dimensional dynamical syst
 em. An example of a conclusion derived from such reductions is the idea of
  a big bang cosmology in general relativity. Such reductions are physicall
 y justified by the working assumption that when viewed from the largest sc
 ales\, the inhomogeneities average out and the matter content can be appro
 ximated by a homogeneous compressible fluid. Jointly with Shih-Fang Yeh\, 
 we probe whether this working assumption is justified mathematically. Our 
 results show that on the cosmological timescale\, some big bang solutions 
 are susceptible to instabilities generated through nonlinear self-interact
 ions of the constituent matter when inhomogeneities are present. The goal 
 of this talk is to present the mathematical context of this result and bri
 efly describe the mechanism driving the instability\, focusing on the rele
 vance of the conformal (or causal) geometry of the big bang solutions. (No
  prior familiarity with mathematical relativity is assumed.)\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/56/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Prof. Thomas Hou (Caltech)
DTSTART:20241105T010000Z
DTEND:20241105T020000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/57
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/57/">A computer assisted proof of finite time singul
 arity of 3D Euler equations with smooth data</a>\nby Prof. Thomas Hou (Cal
 tech) as part of Nonlinear Analysis Seminar Series\n\nLecture held in Room
  M210 in NTNU Gongguan Campus Mathematics Building.\n\nAbstract\nWhether t
 he 3D incompressible Euler equations can develop a finite time singularity
  from smooth initial data is one of the most challenging problems in nonli
 near PDEs. In this talk\, I will present a recent result with Dr. Jiajie C
 hen in which we prove finite time blowup of the 2D Boussinesq and 3D Euler
  equations with smooth initial data and boundary. There are several essent
 ial difficulties in establishing such blowup result. We use the dynamic re
 scaling formulation and turn the problem of proving finite time singularit
 y into a problem of proving stability of an approximate self-similar profi
 le. A crucial step is to establish linear stability of the approximate sel
 f-similar profile. We decompose the solution operator into a leading order
  operator with the desired stability property plus a finite rank perturbat
 ion operator that can be estimated with computer assistance. This enables 
 us to establish nonlinear stability of the approximate self-similar profil
 e and prove stable nearly self-similar blowup of the 2D Boussinesq and 3D 
 Euler equations.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/57/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Prof. Luis Silvestre (University of Chicago)
DTSTART:20241029T010000Z
DTEND:20241029T020000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/58
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/58/">The Landau equation does not blow up</a>\nby Pr
 of. Luis Silvestre (University of Chicago) as part of Nonlinear Analysis S
 eminar Series\n\nLecture held in Room M210 in NTNU Gongguan Campus Mathema
 tics Building.\n\nAbstract\nThe Landau equation is one of the main equatio
 ns in kinetic theory. It models the evolution of the density of particles 
 when they are assumed to repel each other by Coulomb potentials. It is a l
 imit case of the Boltzmann equation with very soft potentials. In the spac
 e-homogeneous case\, we show that the Fisher information is monotone decre
 asing in time. As a consequence\, we deduce that for any initial data the 
 solutions stay smooth and never blow up\, closing a well-known open proble
 m in the area.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/58/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Prof. Thomas Schmidt (University of Hamburg)
DTSTART:20241112T073000Z
DTEND:20241112T083000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/59
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/59/">Isoperimetric conditions and lower semicontinui
 ty for functionals with measures</a>\nby Prof. Thomas Schmidt (University 
 of Hamburg) as part of Nonlinear Analysis Seminar Series\n\nLecture held i
 n Room M210 in NTNU Gongguan Campus Mathematics Building.\n\nAbstract\nThe
  talk deals with functionals in the calculus of variations which are the s
 um of a perimeter or total variation term and a $\\mu$-volume term. Here\,
  $\\mu$ is a possibly lower-dimensional signed measure which has the role 
 of a given right-hand side in corresponding Euler equations. Lower semicon
 tinuity and existence results will be shown to depend crucially on certain
  (small-volume) isoperimetric conditions for $\\mu$. These conditions admi
 t a wide class of measures up to the critical case of area measures on hyp
 ersurfaces and are partially optimal and interesting in themselves. The ge
 neral theory will be illustrated with examples. Some of the results have b
 een obtained in a joint work with E. Ficola (Hamburg).\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/59/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Prof. Franz Gmeineder (University of Konstanz)
DTSTART:20241203T073000Z
DTEND:20241203T083000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/60
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/60/">Extensions and differential constraints</a>\nby
  Prof. Franz Gmeineder (University of Konstanz) as part of Nonlinear Analy
 sis Seminar Series\n\nLecture held in Room M212 in NTNU Gongguan Campus Ma
 thematics Building.\n\nAbstract\nExtension operators are at the core of st
 udying function spaces\, allowing us to reduce numerous problems on domain
 s to those on full space. While this theme has witnessed a huge number of 
 contributions over the past century\, very little is known on extension op
 erators that preserve certain differential constraints. In this talk\, we 
 will give a rather complete picture for divergence-type constraints\, wher
 e we put a special focus on the borderline case $p=1$ and thereby answer a
  borderline case left open by Kato\, Mitrea\, Ponce & Taylor. This is join
 t work with Stefan Schiffer (MPI MIS Leipzig).\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/60/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Prof. Eitan Tadmor (University of Maryland\, College Park)
DTSTART:20241210T010000Z
DTEND:20241210T020000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/61
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/61/">Hierarchical construction of images and the pro
 blem of Bourgain-Brezis</a>\nby Prof. Eitan Tadmor (University of Maryland
 \, College Park) as part of Nonlinear Analysis Seminar Series\n\nLecture h
 eld in Room M212 in NTNU Gongguan Campus Mathematics Building.\n\nAbstract
 \nEdges are noticeable features in images which can be extracted from nois
 y data using different variational models. The analysis of such models lea
 ds to the question of expressing general $L^2$-data\, $f$\, as the diverge
 nce of uniformly bounded vector fields\, $div(U)$. \nWe present a multi-sc
 ale approach to construct uniformly bounded solutions of $div(U)=f$ for ge
 neral $f$’s in the critical regularity space $L^d(T^d)$. The study of th
 is equation and related problems was motivated by results of Bourgain & Br
 ezis. The intriguing critical aspect here is that although the problems ar
 e linear\, construction of their solution is not. These constructions are 
 special cases of a rather general framework for solving linear equations\,
  formulated as inverse problems in critical regularity spaces. The solutio
 ns are realized in terms of nonlinear hierarchical representations $U=\\su
 m_j u_j$  which we introduced earlier in the context of image processing\,
  and yield a multi-scale decomposition of “objects” U.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/61/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Dr. Polona Durcik (Chapman University)
DTSTART:20250506T010000Z
DTEND:20250506T020000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/62
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/62/">On trilinear singular Brascamp-Lieb forms</a>\n
 by Dr. Polona Durcik (Chapman University) as part of Nonlinear Analysis Se
 minar Series\n\nLecture held in Room M210 in NTNU Gongguan Campus Mathemat
 ics Building.\n\nAbstract\nBrascamp-Lieb forms are multilinear integral fo
 rms acting on functions on Euclidean spaces. A necessary and sufficient co
 ndition for their boundedness on Lebesgue spaces is known. Singular Brasca
 mp-Lieb forms arise when one of the functions in a classical Brascamp-Lieb
  form is replaced by a singular integral kernel. Examples include Coifman-
 Meyer multipliers and multilinear Hilbert transforms. A general necessary 
 and sufficient condition for the boundedness of singular Brascamp-Lieb for
 ms remains unknown\, and their theory continues to be developed on a case-
 by-case basis. In this talk\, we classify all trilinear singular Brascamp-
 Lieb forms and establish bounds for a specific class of forms that natural
 ly emerge from this classification. Additionally\, we provide a survey of 
 the literature and briefly discuss conditional bounds for forms associated
  with mutually related representations. This talk is based on joint work w
 ith Lars Becker and Fred Yu-Hsiang Lin.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/62/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Dr. Bochen Liu (Southern University of Science and Technology)
DTSTART:20251028T010000Z
DTEND:20251028T020000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/63
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/63/">Fourier frames on measures with Fourier decay</
 a>\nby Dr. Bochen Liu (Southern University of Science and Technology) as p
 art of Nonlinear Analysis Seminar Series\n\nLecture held in Room M212 in N
 TNU Gongguan Campus Mathematics Building.\n\nAbstract\nIn this talk we sha
 ll discuss the (non)existence of Fourier frames on measures with Fourier d
 ecay. In dimension 2 and higher we only focus on surfaces with nonvanishin
 g Gaussian curvature\, while in the unit interval we consider all existing
  constructions of Salem measures in the literature.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/63/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Dr. Zane Li (North Carolina State University)
DTSTART:20250401T010000Z
DTEND:20250401T020000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/64
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/64/">Mixed norm decoupling for paraboloids</a>\nby D
 r. Zane Li (North Carolina State University) as part of Nonlinear Analysis
  Seminar Series\n\nLecture held in Room M210 in NTNU Gongguan Campus Mathe
 matics Building.\n\nAbstract\nIn this talk we discuss mixed norm decouplin
 g estimates for the paraboloid. One motivation of considering such an esti
 mate is a conjectured mixed norm Strichartz estimate on the torus which es
 sentially is an estimate about exponential sums. This is joint work with S
 hival Dasu\, Hongki Jung\, and José Madrid.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/64/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Dr. Alan Chang (Washington University in St. Louis)
DTSTART:20250408T010000Z
DTEND:20250408T020000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/65
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/65/">Venetian blinds\, digital sundials\, and effici
 ent coverings</a>\nby Dr. Alan Chang (Washington University in St. Louis) 
 as part of Nonlinear Analysis Seminar Series\n\nLecture held in Room M210 
 in NTNU Gongguan Campus Mathematics Building.\n\nAbstract\nDavies's effici
 ent covering theorem states that we can cover any measurable set in the pl
 ane by lines without increasing the total measure. This result has a dual 
 formulation\, known as Falconer's digital sundial theorem\, which states t
 hat we can construct a set in the plane to have any desired projections\, 
 up to null sets. The argument relies on a Venetian blind construction\, a 
 classical method in geometric measure theory. In joint work with Alex McDo
 nald and Krystal Taylor\, we study a variant of Davies's efficient coverin
 g theorem in which we replace lines with curves. This has a dual formulati
 on in terms of nonlinear projections.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/65/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Dr. Myles Workman (National Taiwan Normal University)
DTSTART:20250325T010000Z
DTEND:20250325T020000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/66
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/66/">Minimal hypersurfaces: bubble convergence and i
 ndex</a>\nby Dr. Myles Workman (National Taiwan Normal University) as part
  of Nonlinear Analysis Seminar Series\n\nLecture held in Room M210 in NTNU
  Gongguan Campus Mathematics Building.\n\nAbstract\nThe regularity theorie
 s of Schoen--Simon--Yau and Schoen--Simon for stable minimal hypersurfaces
  are foundational in geometric analysis. Using this regularity theory\, in
  low dimensions\, Chodosh--Ketover--Maximo\, and Buzano--Sharp\, studied s
 ingularity formation along sequences of minimal hypersurfaces through a bu
 bble analysis.\n\nI will review this background\, before talking about my 
 recent work in this bubble analysis theory. In particular I will show how 
 to obtain upper semicontinuity of index plus nullity along a bubble conver
 ging sequence of minimal hypersurfaces.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/66/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Dr. Hiroki Saito (Nihon University)
DTSTART:20250513T020000Z
DTEND:20250513T030000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/67
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/67/">Infinitesimal $L^{p}\\to L^{q}$ relative bounds
  for $(-\\Delta)^{\\alpha/2}+v$</a>\nby Dr. Hiroki Saito (Nihon University
 ) as part of Nonlinear Analysis Seminar Series\n\nLecture held in Room M21
 0 in NTNU Gongguan Campus Mathematics Building.\n\nAbstract\nBy analyzing 
 the trace inequality for Bessel potentials\,\nsome Morrey-type sufficient 
 conditions are given \nfor which $L^p\\to L^q$\, $1{<}p\,q<\\infty$\,\ninf
 initesimal relative boundedness of \nthe Schr\\"{o}dinger operators \n$(-\
 \Delta)^{\\alpha/2}+v$ holds.\nThese results provide new aspects of Morrey
  spaces and \na nice application of weight theory.\nThis is a joint work w
 ith Prof. N. Hatano\, R. Kawasumi and H. Tanaka.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/67/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Dr. Hitoshi Tanaka (Tsukuba University of Technology)
DTSTART:20250513T010000Z
DTEND:20250513T020000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/68
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/68/">Multilinear embedding theorem for fractional sp
 arse operators</a>\nby Dr. Hitoshi Tanaka (Tsukuba University of Technolog
 y) as part of Nonlinear Analysis Seminar Series\n\nLecture held in Room M2
 10 in NTNU Gongguan Campus Mathematics Building.\n\nAbstract\nUnder $A_p$ 
 condition for weights\,\nwe show some simple sufficient conditions for whi
 ch\nthe multilinear emmbedding theorem holds for fractional sparse operato
 rs.\nChecking this simple sufficient condition\,\nwe demonstrate that theo
 rem for power weights.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/68/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Dr. Nicolau S. Aiex (National Taiwan Normal University)
DTSTART:20250318T010000Z
DTEND:20250318T020000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/69
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/69/">Quantitative estimates on singularities of mini
 mal hypersurfaces</a>\nby Dr. Nicolau S. Aiex (National Taiwan Normal Univ
 ersity) as part of Nonlinear Analysis Seminar Series\n\nLecture held in Ro
 om M210 in NTNU Gongguan Campus Mathematics Building.\n\nAbstract\nWe will
  discuss the occasionally unavoidable presence of singularities\non minima
 l hypersurfaces in high dimensional ambient spaces and\nestimates on its s
 ize.\nThis is seemingly an analysis problem but the variational notion of\
 nminimal hypersurfaces plays a much more important role than its defining\
 nPDE.\nThe proof relies simply on coverings arguments by suitable open set
 s and\nwe will go over the main ideas and consequences.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/69/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Dr. Luca Gennaioli (University of Warwick)
DTSTART:20250429T070000Z
DTEND:20250429T080000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/70
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/70/">On the Fourier transform of BV functions</a>\nb
 y Dr. Luca Gennaioli (University of Warwick) as part of Nonlinear Analysis
  Seminar Series\n\nLecture held in Room M212 in NTNU Gongguan Campus Mathe
 matics Building.\n\nAbstract\nThe plan is to introduce BV functions and th
 e Fourier transform and study how this two objects interact. We will prove
  asymptotic formulae for the Fourier transform of BV functions and (as a c
 orollary) for characteristic functions of sets of finite perimeter. Then w
 e will show how\, using techniques of geometric measure theory\, it is pos
 sible to sharpen some results of Herz\, concerning convergence properties 
 of the Fourier transform of sets. Time permitting\, we will provide some a
 pplications to the isoperimetric inequality and some open problems.\nThis 
 talk is based on a joint work with Thomas Beretti (SISSA\, Trieste).\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/70/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Dr. Alexander Tyulenev (Steklov Mathematical Institute)
DTSTART:20251104T070000Z
DTEND:20251104T080000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/71
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/71/">Traces of weighted Sobolev spaces in the limiti
 ng case</a>\nby Dr. Alexander Tyulenev (Steklov Mathematical Institute) as
  part of Nonlinear Analysis Seminar Series\n\nLecture held in Room M212 in
  NTNU Gongguan Campus Mathematics Building.\n\nAbstract\nA complete descri
 ption of traces on  $\\mathbb{R}^{n}$  of functions from the weighted Sobo
 lev space\n$W^{l}_{1}(\\mathbb{R}^{n+1}\,\\gamma)$\, $l \\in \\mathbb{N}$\
 , with weight  $\\gamma \\in A^{\\rm loc}_{1}(\\mathbb{R}^{n+1})$ will be 
 presented.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/71/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Dr. Jaemin Park (Yonsei University)
DTSTART:20251014T070000Z
DTEND:20251014T080000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/72
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/72/">No anomalous dissipation in two dimensional flu
 ids</a>\nby Dr. Jaemin Park (Yonsei University) as part of Nonlinear Analy
 sis Seminar Series\n\nLecture held in Room M212 in NTNU Gongguan Campus Ma
 thematics Building.\n\nAbstract\nIn this talk\, we will discuss Leray-Hopf
  solutions to the incompressible Navier-Stokes equations with vanishing vi
 scosity. We explore important features of turbulence\, focusing around the
  anomalous energy dissipation phenomenon. As a related result\, I will pre
 sent a recent result proving that for two-dimensional fluids\, assuming th
 at  the initial vorticity is merely a Radon measure with nonnegative singu
 lar part\, there is no anomalous energy dissipation. Our proof draws on se
 veral key observations from the work of J. Delort (1991) on constructing g
 lobal weak solutions to the Euler equation. We will also discuss possible 
 extensions to the viscous SQG equation in the context of Hamiltonian conse
 rvation and existence of weak solutions for a rough initial data. This is 
 a joint work with Mikael Latocca (Univ. Evry) and Luigi De Rosa (GSSI).\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/72/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Dr. Sung-Jin Oh (University of California\, Berkeley)
DTSTART:20250909T010000Z
DTEND:20250909T020000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/73
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/73/">Integral formulas for under/overdetermined diff
 erential operators via recovery on curves and the finite-dimensional coker
 nel condition</a>\nby Dr. Sung-Jin Oh (University of California\, Berkeley
 ) as part of Nonlinear Analysis Seminar Series\n\nLecture held in Room M21
 2 in NTNU Gongguan Campus Mathematics Building.\n\nAbstract\nUnderdetermin
 ed differential operators arise naturally in diverse areas of physics and 
 geometry\, including the divergence-free condition for incompressible flui
 ds\, the linearized scalar curvature operator in Riemannian geometry\, and
  the constraint equations in general relativity. The duals of underdetermi
 ned operators\, which are overdetermined\, also play a significant role. I
 n this talk\, I will present recent joint work with Philip Isett (Caltech)
 \, Yuchen Mao (UC Berkeley)\, and Zhongkai Tao (IHÉS) that introduces a n
 ovel approach - called recovery on curves - to constructing integral solut
 ion/representation formulas (i.e.\, right-/left-inverses) for a broad clas
 s of under/overdetermined operators via solving ODEs on curves. They are o
 ptimally regularizing and have prescribed support properties (e.g.\, produ
 ce compactly supported solutions for compactly supported forcing terms). A
  key feature of our approach is a simple algebraic condition on the princi
 pal symbol - called the finite-dimensional cokernel (FC) condition - that 
 implies the applicability of our method. This condition simplifies and uni
 fies various treatments of related problems in the literature. If time per
 mits\, I will discuss applications to studying the flexibility of initial 
 data sets in general relativity.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/73/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Dr. Elia Brué (Università Bocconi)
DTSTART:20250923T070000Z
DTEND:20250923T080000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/74
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/74/">Non-Uniqueness and Flexibility in Two-Dimension
 al Euler Equations</a>\nby Dr. Elia Brué (Università Bocconi) as part of
  Nonlinear Analysis Seminar Series\n\nLecture held in Room M212 in NTNU Go
 ngguan Campus Mathematics Building.\n\nAbstract\nIn 1962\, Yudovich establ
 ished the well-posedness of the two-dimensional incompressible Euler equat
 ions for solutions with bounded vorticity. However\, uniqueness within the
  broader class of solutions with L^p vorticity remains a key unresolved qu
 estion. In this talk\, I will survey recent advances on this problem and p
 resent new nonuniqueness results\, obtained via the convex integration met
 hod. This work is in collaboration with Colombo and Kumar.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/74/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Dr. Surjeet Choudhary (National Center for Theoretical Sciences\, 
 Taiwan)
DTSTART:20251021T070000Z
DTEND:20251021T080000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/75
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/75/">Twisted bilinear spherical maximal functions</a
 >\nby Dr. Surjeet Choudhary (National Center for Theoretical Sciences\, Ta
 iwan) as part of Nonlinear Analysis Seminar Series\n\nLecture held in Room
  M210 in NTNU Gongguan Campus Mathematics Building.\n\nAbstract\nIn this t
 alk\, we will discuss $L^p−$estimates for the full and lacunary maximal 
 functions associated with the twisted bilinear spherical averages given by
 \n\\[\\mathfrak{A}_t(f_1\,f_2)(x\,y)=\\int_{\\mathbb S^{2d-1}}f_1(x+tz_1\,
 y)f_2(x\,y+tz_2)\\\;d\\sigma(z_1\,z_2)\,\\\;t>0\,\\]\nfor all dimensions $
 d\\geq1$.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/75/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Dr.  Alexander Nabutovsky (University of Toronto)
DTSTART:20251111T010000Z
DTEND:20251111T020000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/76
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/76/">Boxing inequalities\, widths\, and systolic geo
 metry</a>\nby Dr.  Alexander Nabutovsky (University of Toronto) as part of
  Nonlinear Analysis Seminar Series\n\nLecture held in Room M212 in NTNU Go
 ngguan Campus Mathematics Building.\n\nAbstract\nWe will present generaliz
 ations of the classical boxing inequality:\nFor a bounded domain $\\Omega\
 \subset \\mathbb{R}^{n+1}$ and a positive $m\\in (0\,n]$ ${\\rm HC}_m(\\Om
 ega)\\leq c(m){\\rm HC}_m(\\partial\\Omega)$\, where ${\\rm HC}_m$ denotes
  the $m$-dimensional Hausdorff content. Recall that ${\\rm HC}_m(X)$ is de
 fined as the infimum of $\\Sigma_i r_i^m$ over all coverings of $X$ by met
 ric balls\, where $r_i$ denote the radii of these balls.\nThe case $m=n$ h
 ere is the classical boxing inequality that is stronger than the isoperime
 tric inequality. \n\nYet this result is only a particular case of our boxi
 ng inequality valid also in higher codimensions: For each Banach space $B$
  and compact $M\\subset B$ there is a ``filling" of $M$ by $W$ so that\n$W
 $ is at the distance at most $c(m){\\rm HC}^{1\\over m}_m(M)$ from $M$ and
  ${\\rm HC}_m(W)\\leq const(m){\\rm HC}_m(M)$. This result can be further 
 generalized to the case where the ambient space $B$ is a metric space with
  a linear contractibility function.\n\nThis result generalizes the high-co
 dimension isoperimetric inequality for Hausdorff contents proven by B. Lis
 hak\, Y. Liokumovich\, R. Rotman and the speaker originally motivated by a
 pplications to systolic geometry.\n\nThe applications to systolic geometry
  involve inequalities that provide upper bounds\nfor the widths of $M\\sub
 set B$ in terms of volume or Hausdorff contents of $M$. The widths $W_m^B(
 M)$ measure how far $M$ is from a $m$-dimensional simplicial complex in $B
 $. In the second part of the talk we will explain the new inequality $W_{m
 -1}^{l^\\infty}(M)\\leq {\\rm const} \\sqrt{m}\\ vol(M^m)^{1\\over m}$ for
  closed manifolds $M^m\\subset{\\mathbb R}^N$ and its implications to syst
 olic geometry. Here\, the width is measured with respect to the $l^\\infty
 $ distance in the ambient Euclidean space.\n\nJoint work with Sergey Avvak
 umov.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/76/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Dr. Paz Hashash (Ben Gurion University of the Negev)
DTSTART:20251118T070000Z
DTEND:20251118T080000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/77
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/77/">The refined area formula for Sobolev mappings</
 a>\nby Dr. Paz Hashash (Ben Gurion University of the Negev) as part of Non
 linear Analysis Seminar Series\n\nLecture held in Room M212 in NTNU Gonggu
 an Campus Mathematics Building.\n\nAbstract\nWe present a refined area for
 mula for Sobolev mappings \n$\\varphi : \\Omega \\to \\mathbb{R}^n$.\nThe 
 classical identity\n\\[\n\\int_\\Omega f(x)\\\,|J\\varphi(x)|\\\,dx\n  = \
 \int_{\\mathbb{R}^n} \\sum_{x\\in\\varphi^{-1}\\{y\\}} f(x)\\\,dy\n\\]\ndo
 es not hold in general\, since Sobolev mappings are not differentiable on 
 large sets.\nWe show that the formula is valid once we remove an exception
 al set of vanishing Riesz capacity.\nThe argument uses Lipschitz approxima
 tion of Sobolev mappings on subsets where the capacity is large.\nOn these
  subsets we apply the usual area formula\, and then pass to the limit.\nTh
 is gives an extension of the change of variables formula beyond the Lipsch
 itz case.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/77/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Long Huang (Guangzhou University)
DTSTART:20260303T070000Z
DTEND:20260303T080000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/78
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/78/">Capacitary Muckenhoupt weights</a>\nby Long Hua
 ng (Guangzhou University) as part of Nonlinear Analysis Seminar Series\n\n
 Lecture held in Room M210 in NTNU Gongguan Campus Mathematics Building.\n\
 nAbstract\nIn this talk\, we mainly introduce a new class of capacitary Mu
 ckenhoupt weights denoted by A_{p\,\\delta}. It is proved to be a proper 
 subset of standard Muckenhoupt's A_p weight. By proposing a new approach\,
  we then show Muckenhoupt's theorem\, reverse Holder's inequality\, self-i
 mproving property\, and Jones' factorization theorem within this capacitar
 y Muckenhoupt weight framework. Finally\, we will reveal the deep connecti
 ons between A_{p\,\\delta} with BMO and BLO spaces with respect to Hausdor
 ff contents.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/78/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Gabriele Cassese (Oxford University)
DTSTART:20260310T070000Z
DTEND:20260310T080000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/79
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/79/">Martingales\, laminates and Korn-type inequalit
 ies</a>\nby Gabriele Cassese (Oxford University) as part of Nonlinear Anal
 ysis Seminar Series\n\nLecture held in Room M212 in NTNU Gongguan Campus M
 athematics Building.\n\nAbstract\nKorn-type inequalities quantify a fundam
 ental rigidity principle in linear elasticity: the size of the full gradie
 nt of a displacement can be controlled by a reduced set of “strain-like
 ” quantities. Motivated by a question of Chipot\, one can ask for a mini
 mal version of this principle: how many scalar linear measurements of the 
 gradient does one need to control the whole gradient? I will present a ref
 ormulation of this problem in terms of rank-one convexity and quasiconvexi
 ty\, leading to sharp bounds. A central new ingredient is a systematic con
 nection between laminates and martingales\, which produces explicit famili
 es realising the extremal behaviour. The same construction gives a streaml
 ined\, quantitative route to Ornstein-type non-inequalities for broad clas
 ses of first-order homogeneous operators. If time permits\, I will discuss
  additional applications of this method to calculus of variations\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/79/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Paolo Bonicatto (University of Trento)
DTSTART:20260428T070000Z
DTEND:20260428T080000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/80
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/80/">Geometric Transport Equation for currents: rece
 nt developments</a>\nby Paolo Bonicatto (University of Trento) as part of 
 Nonlinear Analysis Seminar Series\n\nLecture held in Room M212 in NTNU Gon
 gguan Campus Mathematics Building.\n\nAbstract\nI will report on recent re
 sults concerning the Geometric Transport Equation for $k$-dimensional curr
 ents in $\\mathbb R^n$. This equation generalises the classical continuity
  and transport equations to model the motion of geometric objects such as 
 lines and surfaces. I will discuss well-posedness results for Lipschitz ve
 locity fields\, highlighting a deep connection with the notion of decompos
 ability bundle of a measure (introduced by Alberti and Marchese). This the
 ory further extends to the time-dependent setting with minimal regularity 
 in time of the vector field\, thus offering a unified framework for the ev
 olution of geometric data under non-smooth flows. If time allows\, I will 
 also outline a recent approach to the classical Frobenius’ theorem via t
 he transport of currents. The vanishing bracket condition is recast into t
 ransport identities that remain meaningful even when one of the vector fie
 lds is a normal 1-current and this perspective sheds light on some Alfvén
 -type statements in magnetohydrodynamics.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/80/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Yohei Tsutsui (Kyoto University)
DTSTART:20260317T010000Z
DTEND:20260317T020000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/81
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/81/">Another proof of Alvino's embedding via medians
 </a>\nby Yohei Tsutsui (Kyoto University) as part of Nonlinear Analysis Se
 minar Series\n\nLecture held in 台灣大學次震宇宙館509研討室+ Z
 oom.\n\nAbstract\nThe median of a function on Euclidean space was introduc
 ed by F. John in 1965\, and can be regarded as a type of average. Unlike t
 he integral average\, even for non-integrable functions\, a median always 
 exists. However\, the median is not unique\, in general. In fact\, it is w
 ell-known that the set of all medians for a function is a closed interval.
  With the aid of a result due to Poelhuis and Torchinsky (2012)\, we can s
 ee that the endpoints of the closed interval are two distinct rearrangemen
 ts. We introduce a fractional version of medians and give a similar expres
 sion for the set of all fractional medians. We introduce the maximal opera
 tor defined via medians instead of integral averages\, and establish smoot
 hing properties for the fractional maximal operator. Finally\, we give a s
 hort proof of Alvino's embedding\, $L^{n/(n-1)\,1} \\to BV$ by using prope
 rties of medians and the coarea formula. Our estimate is covered by a resu
 lt by Spector (2020).\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/81/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Hiroki Ohyama (Kyoto University)
DTSTART:20260317T020000Z
DTEND:20260317T030000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/82
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/82/">Long-time solvability and asymptotics for the 3
 D rotating MHD equations</a>\nby Hiroki Ohyama (Kyoto University) as part 
 of Nonlinear Analysis Seminar Series\n\nLecture held in 台灣大學次震
 宇宙館509研討室+ Zoom.\n\nAbstract\nWe consider the initial value pr
 oblem for the 3D incompressible rotating MHD equations around a constant m
 agnetic field. We prove the long-time existence and uniqueness of solution
 s for small viscosity coefficient and high rotating speed. Moreover\, we i
 nvestigate the asymptotic behavior of solutions in the limit of vanishing 
 viscosity and fast rotation\, and show that the velocity and magnetic fiel
 d converge to the zero vector and the solution to the linear heat equation
 \, respectively. We also derive the rates of these convergences in some sp
 ace-time norm.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/82/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Marco Caroccia (University of Firenze)
DTSTART:20260324T070000Z
DTEND:20260324T080000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/83
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/83/">On the contact surface of Cheeger sets</a>\nby 
 Marco Caroccia (University of Firenze) as part of Nonlinear Analysis Semin
 ar Series\n\nLecture held in Room M212 in NTNU Gongguan Campus Mathematics
  Building.\n\nAbstract\nGeometrical properties of Cheeger sets have been d
 eeply studied by many authors since their introduction\, as a way of bound
 ing from below the first Dirichlet p-Laplacian eigenvalue. They represent\
 , in some sense\, the first eigenfunction of the Dirichlet 1-Laplacian of 
 a domain. In this talk we will introduce a property\, studied in collabora
 tion with Simone Ciani\, concerning their contact surface with the ambient
  space. In particular\, we will show that the contact surface cannot be to
 o small\, with a lower bound on the (Hausdorff) dimension strictly related
  to the regularity of the ambient space. The talk will focus on the introd
 uction of the problem and on the proof of the dimensional bounds. Function
 al to the whole argument is the notion of removable singularity\, as a too
 l for extending solutions of PDEs under some regularity constraint. Finall
 y\, examples providing the sharpness of the bounds in the planar case are 
 briefly treated.\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/83/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Wenqi Zhang (The Australian National University)
DTSTART:20260414T010000Z
DTEND:20260414T020000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/84
DESCRIPTION:by Wenqi Zhang (The Australian National University) as part of
  Nonlinear Analysis Seminar Series\n\nLecture held in Room M212 in NTNU Go
 ngguan Campus Mathematics Building.\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/84/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Quoc-Hung Nguyen (Academy of Mathematics and Systems Science)
DTSTART:20260331T070000Z
DTEND:20260331T080000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/85
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/Nonli
 near_Analysis_Seminar/85/">The 3D Inhomogeneous Incompressible Navier–St
 okes System with ( \\mathbf{BMO}^{-1} ) Data</a>\nby Quoc-Hung Nguyen (Aca
 demy of Mathematics and Systems Science) as part of Nonlinear Analysis Sem
 inar Series\n\nLecture held in Room M212 in NTNU Gongguan Campus Mathemati
 cs Building.\n\nAbstract\nWe study the three-dimensional inhomogeneous inc
 ompressible Navier–Stokes equations with rough initial velocity data. We
  first establish the local existence of strong solutions when the initial 
 density is smooth and the velocity belongs to\n( L^2 \\cap \\mathbf{VMO}^{
 -1} ). Moreover\, under a smallness condition on the (\\mathbf{BMO}^{-1} -
 norm of the initial velocity\, we prove global existence of solutions.\nTh
 e proof relies on a new estimate for the transport equation\, which provid
 es regularity of the density\, together with a freezing-coefficient method
  for the velocity equation\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/85/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Josh Kline (University of Cincinnati)
DTSTART:20260505T010000Z
DTEND:20260505T020000Z
DTSTAMP:20260404T110741Z
UID:Nonlinear_Analysis_Seminar/86
DESCRIPTION:by Josh Kline (University of Cincinnati) as part of Nonlinear 
 Analysis Seminar Series\n\nLecture held in Room M212 in NTNU Gongguan Camp
 us Mathematics Building.\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/Nonlinear_Analysis_Semin
 ar/86/
END:VEVENT
END:VCALENDAR