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BEGIN:VEVENT
SUMMARY:Olivier Le Gal (Université Savoie Mont-Blanc)
DTSTART:20210524T120000Z
DTEND:20210524T130000Z
DTSTAMP:20260418T094802Z
UID:ScReGeFor/1
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/ScReGeFor/1/
 ">Topics in O-minimal Geometry\, Lecture 1</a>\nby Olivier Le Gal (Univers
 ité Savoie Mont-Blanc) as part of School of Real Geometry in Fortaleza - 
 ScReGeFor\n\n\nAbstract\nLecture 1. Semi-algebraic sets: definition and ba
 sic properties\, Tarski\, cell decomposition\, dimension.\n\n--\n\nWe invi
 ted Olivier le Gal to present the fundamental notions of o-Minimal Geometr
 y\, starting with the foundational example of the semi-algebraic structure
 . As a specialist in o-minimal geometry he will hint at how the four other
 s courses are related.\n
LOCATION:https://researchseminars.org/talk/ScReGeFor/1/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Goulwen Fichou (Université de Rennes I)
DTSTART:20210524T131500Z
DTEND:20210524T141500Z
DTSTAMP:20260418T094802Z
UID:ScReGeFor/2
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/ScReGeFor/2/
 ">Regulous Functions\, Lecture 1</a>\nby Goulwen Fichou (Université de Re
 nnes I) as part of School of Real Geometry in Fortaleza - ScReGeFor\n\n\nA
 bstract\nLecture 1. What is a regulous function? Typical example on the re
 al plane\, history\, strange behavior on singular sets.\n\n--\n\nRegulous 
 function (continuous extensions of rational functions) have appeared almos
 t twenty years ago in the works of ​Kollár and Nowak. In the last six y
 ears they have been the focus of some serious interest. Goulwen Fichou wil
 l present us this category of functions and their specs as well as many cu
 rrent problems of Real Geometry where they naturally appear.\n
LOCATION:https://researchseminars.org/talk/ScReGeFor/2/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Fernando Sanz (Universidad de Valladolid)
DTSTART:20210524T144500Z
DTEND:20210524T154500Z
DTSTAMP:20260418T094802Z
UID:ScReGeFor/3
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/ScReGeFor/3/
 ">Non-Oscillating Trajectories of Vector Fields\, Lecture 1</a>\nby Fernan
 do Sanz (Universidad de Valladolid) as part of School of Real Geometry in 
 Fortaleza - ScReGeFor\n\n\nAbstract\nA very interesting setting where Real
  Analytic Geometry interacts with Model Theory concerns the asymptotic beh
 aviour of trajectories of real analytic vector fields at singular points\,
  either as a single object or as pencils of such objects. Little is known 
 is general and\, yet\, there are many partial results and examples about t
 his appealing topic. Fernando Sanz will tell us more about this\, and if t
 imes allows will be able to speak of some of his latest results and share 
 a few hopes for still open problems.\n
LOCATION:https://researchseminars.org/talk/ScReGeFor/3/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Armin Rainer (Universität Wien)
DTSTART:20210524T160000Z
DTEND:20210524T170000Z
DTSTAMP:20260418T094802Z
UID:ScReGeFor/4
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/ScReGeFor/4/
 ">From Ultra-differentiable to Quasi-Analytic Analysis\, Lecture 1</a>\nby
  Armin Rainer (Universität Wien) as part of School of Real Geometry in Fo
 rtaleza - ScReGeFor\n\n\nAbstract\nThe mini-course is intended as an intro
 duction to ultradifferential analysis with special emphasis on ultra-diffe
 rentiable extension theorems. The development of differential analysis in 
 the last century was decisively influenced by Whitney’s work on the exte
 nsion of differentiable functions from closed sets. We shall be interested
  in quantitative versions of Whitney’s extension theorem. The quantitati
 ve aspect is implemented by uniform growth properties of the multisequence
  of partial derivatives which measure the deviation from the Cauchy estima
 tes and hence from analyticity. These growth conditions determine ultradif
 ferentiable function classes which form a scale of regularity classes betw
 een the real analytic and the smooth class.\n\nLecture 1. We will recall W
 hitney’s classical extension theorem and formulate the quantitative prob
 lem. This will lead us to Denjoy–Carleman classes which are the ultradif
 ferentiable classes of main interest in this series of lectures. After dis
 cussing inclusion and stability properties we shall begin with the study o
 f the Borel map (i.e. infinite Taylor expansion) on Denjoy–Carleman clas
 ses. We will investigate when the Borel map is injective and\, in the cour
 se of this\, prove the Denjoy–Carleman theorem which discriminates betwe
 en quasianalytic and non-quasianalytic classes.\n\n--\n\nUltra-differentia
 ble Analysis concerns sub-algebras of smooth functions with constrained gr
 owth of the Taylor series coefficients. Besides its importance in the anal
 ysis of partial differential equations the development of this theory was 
 influenced by the classical Whitney extension problem and the composition 
 problem. Both problems followed a path that often meets sub-analytic geome
 try\, and later o-minimal geometry. Of special interest among the ultra-di
 fferentiable classes are the quasi-analytic classes which possess a (quasi
 -)analytic continuation property similar to the real analytic class. This 
 property make these classes interesting from an analytic viewpoint and als
 o suitable for questions of tame geometry. In relation with asymptotic exp
 ansions of solutions of analytic ODEs they also naturally appear when deal
 ing with non-oscillation problems of the solutions. Armin Rainer will intr
 oduce us to ultra-differentiable classes\, in particular to quasi-analytic
  ones.\n
LOCATION:https://researchseminars.org/talk/ScReGeFor/4/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Nicolas Dutertre (Université d'Angers)
DTSTART:20210525T120000Z
DTEND:20210525T130000Z
DTSTAMP:20260418T094802Z
UID:ScReGeFor/5
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/ScReGeFor/5/
 ">Real Equisingularity and Curvature Measures\, Lecture 1</a>\nby Nicolas 
 Dutertre (Université d'Angers) as part of School of Real Geometry in Fort
 aleza - ScReGeFor\n\n\nAbstract\nLecture 1. On the topology of semi-algebr
 aic sets: stratified critical points and an index theorem.\n\n--\n\nUnlike
  their complex counterparts\, equisingularity results for tame families of
  subsets are harder to come by in Real Tame Geometry. Nevertheless a promi
 sing\, though not unexpected\, approach is to walk in the world of integra
 l geometry and get sufficient conditions in terms of continuity of certain
  functions built from curvature measures associated with the members of th
 e family. Nicolas Dutertre will introduce us to his tools from Geometric m
 easure theory (Lipschitz-Killing Measures) and how they naturally appear w
 ith good properties in equisingularity problems.\n
LOCATION:https://researchseminars.org/talk/ScReGeFor/5/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Goulwen Fichou (Université de Rennes I)
DTSTART:20210525T131500Z
DTEND:20210525T141500Z
DTSTAMP:20260418T094802Z
UID:ScReGeFor/6
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/ScReGeFor/6/
 ">Regulous Functions\, Lecture 2</a>\nby Goulwen Fichou (Université de Re
 nnes I) as part of School of Real Geometry in Fortaleza - ScReGeFor\n\n\nA
 bstract\nLecture 2. Regulous functions: first properties\, regularity on a
  stratification and regularity after blowings-up.\n\n--\n\nRegulous functi
 on (continuous extensions of rational functions) have appeared almost twen
 ty years ago in the works of ​Kollár and Nowak. In the last six years t
 hey have been the focus of some serious interest. Goulwen Fichou will pres
 ent us this category of functions and their specs as well as many current 
 problems of Real Geometry where they naturally appear.\n
LOCATION:https://researchseminars.org/talk/ScReGeFor/6/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Olivier Le Gal (Université Savoie Mont-Blanc)
DTSTART:20210525T144500Z
DTEND:20210525T154500Z
DTSTAMP:20260418T094802Z
UID:ScReGeFor/7
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/ScReGeFor/7/
 ">Topics in O-minimal Geometry\, Lecture 2</a>\nby Olivier Le Gal (Univers
 ité Savoie Mont-Blanc) as part of School of Real Geometry in Fortaleza - 
 ScReGeFor\n\n\nAbstract\nLecture 2. O-minimality : Definition of an o-mini
 mal expansion of the field of real\, finiteness properties\, selection lem
 ma\, $C^k$.\n\n--\n\nWe invited Olivier le Gal to present the fundamental 
 notions of o-Minimal Geometry\, starting with the foundational example of 
 the semi-algebraic structure. As a specialist in o-minimal geometry he wil
 l hint at how the four others courses are related.\n
LOCATION:https://researchseminars.org/talk/ScReGeFor/7/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Armin Rainer (Universität Wien)
DTSTART:20210525T160000Z
DTEND:20210525T170000Z
DTSTAMP:20260418T094802Z
UID:ScReGeFor/8
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/ScReGeFor/8/
 ">From Ultra-differentiable to Quasi-Analytic Analysis\, Lecture 2</a>\nby
  Armin Rainer (Universität Wien) as part of School of Real Geometry in Fo
 rtaleza - ScReGeFor\n\n\nAbstract\nThe mini-course is intended as an intro
 duction to ultradifferential analysis with special emphasis on ultra-diffe
 rentiable extension theorems. The development of differential analysis in 
 the last century was decisively influenced by Whitney’s work on the exte
 nsion of differentiable functions from closed sets. We shall be interested
  in quantitative versions of Whitney’s extension theorem. The quantitati
 ve aspect is implemented by uniform growth properties of the multisequence
  of partial derivatives which measure the deviation from the Cauchy estima
 tes and hence from analyticity. These growth conditions determine ultradif
 ferentiable function classes which form a scale of regularity classes betw
 een the real analytic and the smooth class.\n\nLecture 2 (Tue\, May 25\, 1
 3:00). Next we will study the image of the Borel map on Denjoy–Carleman 
 classes which naturally sits in the sequence space defined by the characte
 ristic bounds. The quasianalytic and the non-quasianalytic case are fundam
 entally different. While in the non-quasianalytic case we will give necess
 ary and sufficient conditions for the Borel map being onto the sequence sp
 ace\, we shall see that on quasianalytic classes\, strictly containing the
  real analytic class\, the Borel map is never onto. This will be complemen
 ted by some results on the description of the Borel image and a discussion
  of further intricacies of the quasianalytic setting.\n\n--\n\nUltra-diffe
 rentiable Analysis concerns sub-algebras of smooth functions with constrai
 ned growth of the Taylor series coefficients. Besides its importance in th
 e analysis of partial differential equations the development of this theor
 y was influenced by the classical Whitney extension problem and the compos
 ition problem. Both problems followed a path that often meets sub-analytic
  geometry\, and later o-minimal geometry. Of special interest among the ul
 tra-differentiable classes are the quasi-analytic classes which possess a 
 (quasi-)analytic continuation property similar to the real analytic class.
  This property make these classes interesting from an analytic viewpoint a
 nd also suitable for questions of tame geometry. In relation with asymptot
 ic expansions of solutions of analytic ODEs they also naturally appear whe
 n dealing with non-oscillation problems of the solutions. Armin Rainer wil
 l introduce us to ultra-differentiable classes\, in particular to quasi-an
 alytic ones.\n
LOCATION:https://researchseminars.org/talk/ScReGeFor/8/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Nicolas Dutertre (Université d'Angers)
DTSTART:20210526T120000Z
DTEND:20210526T130000Z
DTSTAMP:20260418T094802Z
UID:ScReGeFor/9
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/ScReGeFor/9/
 ">Real Equisingularity and Curvature Measures\, Lecture 2</a>\nby Nicolas 
 Dutertre (Université d'Angers) as part of School of Real Geometry in Fort
 aleza - ScReGeFor\n\n\nAbstract\nLecture 2. Lipschitz-Killing measures and
  Gauss-Bonnet theorems\n\n--\n\nUnlike their complex counterparts\, equisi
 ngularity results for tame families of subsets are harder to come by in Re
 al Tame Geometry. Nevertheless a promising\, though not unexpected\, appro
 ach is to walk in the world of integral geometry and get sufficient condit
 ions in terms of continuity of certain functions built from curvature meas
 ures associated with the members of the family. Nicolas Dutertre will intr
 oduce us to his tools from Geometric measure theory (Lipschitz-Killing Mea
 sures) and how they naturally appear with good properties in equisingulari
 ty problems.\n
LOCATION:https://researchseminars.org/talk/ScReGeFor/9/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Goulwen Fichou (Université de Rennes I)
DTSTART:20210526T131500Z
DTEND:20210526T141500Z
DTSTAMP:20260418T094802Z
UID:ScReGeFor/10
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/ScReGeFor/10
 /">Regulous Functions\, Lecture 3</a>\nby Goulwen Fichou (Université de R
 ennes I) as part of School of Real Geometry in Fortaleza - ScReGeFor\n\n\n
 Abstract\nLecture 3. Łojasiewicz property and real algebra: expansion of 
 continuous function\, Nullstellensatz\, real algebraic versus regulous set
 s.\n\n--\n\nRegulous function (continuous extensions of rational functions
 ) have appeared almost twenty years ago in the works of ​Kollár and Now
 ak. In the last six years they have been the focus of some serious interes
 t. Goulwen Fichou will present us this category of functions and their spe
 cs as well as many current problems of Real Geometry where they naturally 
 appear.\n
LOCATION:https://researchseminars.org/talk/ScReGeFor/10/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Olivier Le Gal (Université Savoie Mont-Blanc)
DTSTART:20210526T144500Z
DTEND:20210526T154500Z
DTSTAMP:20260418T094802Z
UID:ScReGeFor/11
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/ScReGeFor/11
 /">Topics in O-minimal Geometry\, Lecture 3</a>\nby Olivier Le Gal (Univer
 sité Savoie Mont-Blanc) as part of School of Real Geometry in Fortaleza -
  ScReGeFor\n\n\nAbstract\nLecture 3. Polynomial boundedness versus exponen
 tial: Chris Miller's dichotomy growth theorem\, Hardy field of an o-minima
 l structure\, asymptotic of definable functions\, Łojasiewicz inequality 
 in polynomially bounded structures.\n\n--\n\nWe invited Olivier le Gal to 
 present the fundamental notions of o-Minimal Geometry\, starting with the 
 foundational example of the semi-algebraic structure. As a specialist in o
 -minimal geometry he will hint at how the four others courses are related.
 \n
LOCATION:https://researchseminars.org/talk/ScReGeFor/11/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Fernando Sanz (Universidad de Valladolid)
DTSTART:20210526T160000Z
DTEND:20210526T170000Z
DTSTAMP:20260418T094802Z
UID:ScReGeFor/12
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/ScReGeFor/12
 /">Non-Oscillating Trajectories of Vector Fields\, Lecture 2</a>\nby Ferna
 ndo Sanz (Universidad de Valladolid) as part of School of Real Geometry in
  Fortaleza - ScReGeFor\n\n\nAbstract\nA very interesting setting where Rea
 l Analytic Geometry interacts with Model Theory concerns the asymptotic be
 haviour of trajectories of real analytic vector fields at singular points\
 , either as a single object or as pencils of such objects. Little is known
  is general and\, yet\, there are many partial results and examples about 
 this appealing topic. Fernando Sanz will tell us more about this\, and if 
 times allows will be able to speak of some of his latest results and share
  a few hopes for still open problems.\n
LOCATION:https://researchseminars.org/talk/ScReGeFor/12/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Olivier Le Gal (Université Savoie Mont-Blanc)
DTSTART:20210527T120000Z
DTEND:20210527T130000Z
DTSTAMP:20260418T094802Z
UID:ScReGeFor/13
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/ScReGeFor/13
 /">Topics in O-minimal Geometry\, Lecture 4</a>\nby Olivier Le Gal (Univer
 sité Savoie Mont-Blanc) as part of School of Real Geometry in Fortaleza -
  ScReGeFor\n\n\nAbstract\nLecture 4. Quasi-analytic classes and o-minimali
 ty: In this session we deal with the link between quasi-analytic classes a
 nd o-minimality. We review some examples of o-minimal structures generated
  by quasi-analytic classes.\n\n--\n\nWe invited Olivier le Gal to present 
 the fundamental notions of o-Minimal Geometry\, starting with the foundati
 onal example of the semi-algebraic structure. As a specialist in o-minimal
  geometry he will hint at how the four others courses are related.\n
LOCATION:https://researchseminars.org/talk/ScReGeFor/13/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Nicolas Dutertre (Université d'Angers)
DTSTART:20210527T131500Z
DTEND:20210527T141500Z
DTSTAMP:20260418T094802Z
UID:ScReGeFor/14
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/ScReGeFor/14
 /">Real Equisingularity and Curvature Measures\, Lecture 3</a>\nby Nicolas
  Dutertre (Université d'Angers) as part of School of Real Geometry in For
 taleza - ScReGeFor\n\n\nAbstract\nLecture 3. Lipschitz-Killing measures an
 d Gauss-Bonnet theorems\n\n--\n\nUnlike their complex counterparts\, equis
 ingularity results for tame families of subsets are harder to come by in R
 eal Tame Geometry. Nevertheless a promising\, though not unexpected\, appr
 oach is to walk in the world of integral geometry and get sufficient condi
 tions in terms of continuity of certain functions built from curvature mea
 sures associated with the members of the family. Nicolas Dutertre will int
 roduce us to his tools from Geometric measure theory (Lipschitz-Killing Me
 asures) and how they naturally appear with good properties in equisingular
 ity problems.\n
LOCATION:https://researchseminars.org/talk/ScReGeFor/14/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Armin Rainer (Universität Wien)
DTSTART:20210527T144500Z
DTEND:20210527T154500Z
DTSTAMP:20260418T094802Z
UID:ScReGeFor/15
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/ScReGeFor/15
 /">From Ultra-differentiable to Quasi-Analytic Analysis\, Lecture 3</a>\nb
 y Armin Rainer (Universität Wien) as part of School of Real Geometry in F
 ortaleza - ScReGeFor\n\n\nAbstract\nThe mini-course is intended as an intr
 oduction to ultradifferential analysis with special emphasis on ultra-diff
 erentiable extension theorems. The development of differential analysis in
  the last century was decisively influenced by Whitney’s work on the ext
 ension of differentiable functions from closed sets. We shall be intereste
 d in quantitative versions of Whitney’s extension theorem. The quantitat
 ive aspect is implemented by uniform growth properties of the multisequenc
 e of partial derivatives which measure the deviation from the Cauchy estim
 ates and hence from analyticity. These growth conditions determine ultradi
 fferentiable function classes which form a scale of regularity classes bet
 ween the real analytic and the smooth class.\n\nLecture 3. The third lectu
 re is devoted to the Whitney extension problem for arbitrary closed sets. 
 The key ingredient is the existence of optimal cut-off functions which yie
 ld\, in combination with a family of Whitney cubes\, a suitable partition 
 of unity on the complement of the closed set. We shall see that this parti
 tion of unity allows us to glue the local extensions for the singleton (Bo
 rel map) to a global extension. We will also discuss the existence of cont
 inuous linear extension operators which is intimately related to interesti
 ng topological invariants of the involved function spaces.\n\n--\n\nUltra-
 differentiable Analysis concerns sub-algebras of smooth functions with con
 strained growth of the Taylor series coefficients. Besides its importance 
 in the analysis of partial differential equations the development of this 
 theory was influenced by the classical Whitney extension problem and the c
 omposition problem. Both problems followed a path that often meets sub-ana
 lytic geometry\, and later o-minimal geometry. Of special interest among t
 he ultra-differentiable classes are the quasi-analytic classes which posse
 ss a (quasi-)analytic continuation property similar to the real analytic c
 lass. This property make these classes interesting from an analytic viewpo
 int and also suitable for questions of tame geometry. In relation with asy
 mptotic expansions of solutions of analytic ODEs they also naturally appea
 r when dealing with non-oscillation problems of the solutions. Armin Raine
 r will introduce us to ultra-differentiable classes\, in particular to qua
 si-analytic ones.\n
LOCATION:https://researchseminars.org/talk/ScReGeFor/15/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Fernando Sanz (Universidad de Valladolid)
DTSTART:20210527T160000Z
DTEND:20210527T170000Z
DTSTAMP:20260418T094802Z
UID:ScReGeFor/16
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/ScReGeFor/16
 /">Non-Oscillating Trajectories of Vector Fields\, Lecture 3</a>\nby Ferna
 ndo Sanz (Universidad de Valladolid) as part of School of Real Geometry in
  Fortaleza - ScReGeFor\n\n\nAbstract\nA very interesting setting where Rea
 l Analytic Geometry interacts with Model Theory concerns the asymptotic be
 haviour of trajectories of real analytic vector fields at singular points\
 , either as a single object or as pencils of such objects. Little is known
  is general and\, yet\, there are many partial results and examples about 
 this appealing topic. Fernando Sanz will tell us more about this\, and if 
 times allows will be able to speak of some of his latest results and share
  a few hopes for still open problems.\n
LOCATION:https://researchseminars.org/talk/ScReGeFor/16/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Goulwen Fichou (Université de Rennes I)
DTSTART:20210528T120000Z
DTEND:20210528T130000Z
DTSTAMP:20260418T094802Z
UID:ScReGeFor/17
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/ScReGeFor/17
 /">Regulous Functions\, Lecture 4</a>\nby Goulwen Fichou (Université de R
 ennes I) as part of School of Real Geometry in Fortaleza - ScReGeFor\n\n\n
 Abstract\nLecture 4. Advanced results (if time allows): curve rationality\
 , seminormalisation.\n\n--\n\nRegulous function (continuous extensions of 
 rational functions) have appeared almost twenty years ago in the works of 
 ​Kollár and Nowak. In the last six years they have been the focus of so
 me serious interest. Goulwen Fichou will present us this category of funct
 ions and their specs as well as many current problems of Real Geometry whe
 re they naturally appear.\n
LOCATION:https://researchseminars.org/talk/ScReGeFor/17/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Nicolas Dutertre (Université d'Angers)
DTSTART:20210528T131500Z
DTEND:20210528T141500Z
DTSTAMP:20260418T094802Z
UID:ScReGeFor/18
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/ScReGeFor/18
 /">Real Equisingularity and Curvature Measures\, Lecture 4</a>\nby Nicolas
  Dutertre (Université d'Angers) as part of School of Real Geometry in For
 taleza - ScReGeFor\n\n\nAbstract\nLecture 4. Some results on real equising
 ularity.\n\n--\n\nUnlike their complex counterparts\, equisingularity resu
 lts for tame families of subsets are harder to come by in Real Tame Geomet
 ry. Nevertheless a promising\, though not unexpected\, approach is to walk
  in the world of integral geometry and get sufficient conditions in terms 
 of continuity of certain functions built from curvature measures associate
 d with the members of the family. Nicolas Dutertre will introduce us to hi
 s tools from Geometric measure theory (Lipschitz-Killing Measures) and how
  they naturally appear with good properties in equisingularity problems.\n
LOCATION:https://researchseminars.org/talk/ScReGeFor/18/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Armin Rainer (Universität Wien)
DTSTART:20210528T144500Z
DTEND:20210528T154500Z
DTSTAMP:20260418T094802Z
UID:ScReGeFor/19
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/ScReGeFor/19
 /">From Ultra-differentiable to Quasi-Analytic Analysis\, Lecture 4</a>\nb
 y Armin Rainer (Universität Wien) as part of School of Real Geometry in F
 ortaleza - ScReGeFor\n\n\nAbstract\nThe mini-course is intended as an intr
 oduction to ultradifferential analysis with special emphasis on ultra-diff
 erentiable extension theorems. The development of differential analysis in
  the last century was decisively influenced by Whitney’s work on the ext
 ension of differentiable functions from closed sets. We shall be intereste
 d in quantitative versions of Whitney’s extension theorem. The quantitat
 ive aspect is implemented by uniform growth properties of the multisequenc
 e of partial derivatives which measure the deviation from the Cauchy estim
 ates and hence from analyticity. These growth conditions determine ultradi
 fferentiable function classes which form a scale of regularity classes bet
 ween the real analytic and the smooth class.\n\nLecture 4. An ultradiffere
 ntiable Whitney approximation theorem will enable us to conclude that the 
 extension can always be chosen real analytic off the given closed set. Fur
 thermore\, we will discuss the extension problem with a controlled loss of
  regularity. This requires a different approach which is closely related t
 o the characterization of ultradifferentiable classes by almost analytic e
 xtensions. We will address several applications such as Lojasiewicz’s th
 eorem on regularly situated sets or Whitney’s spectral theorem in the ul
 tradifferentiable framework. Finally\, we shall take a glimpse on other ul
 tradifferentiable classes\, in particular\, Braun–Meise–Taylor classes
 .\n\n--\n\nUltra-differentiable Analysis concerns sub-algebras of smooth f
 unctions with constrained growth of the Taylor series coefficients. Beside
 s its importance in the analysis of partial differential equations the dev
 elopment of this theory was influenced by the classical Whitney extension 
 problem and the composition problem. Both problems followed a path that of
 ten meets sub-analytic geometry\, and later o-minimal geometry. Of special
  interest among the ultra-differentiable classes are the quasi-analytic cl
 asses which possess a (quasi-)analytic continuation property similar to th
 e real analytic class. This property make these classes interesting from a
 n analytic viewpoint and also suitable for questions of tame geometry. In 
 relation with asymptotic expansions of solutions of analytic ODEs they als
 o naturally appear when dealing with non-oscillation problems of the solut
 ions. Armin Rainer will introduce us to ultra-differentiable classes\, in 
 particular to quasi-analytic ones.\n
LOCATION:https://researchseminars.org/talk/ScReGeFor/19/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Fernando Sanz (Universidad de Valladolid)
DTSTART:20210528T160000Z
DTEND:20210528T170000Z
DTSTAMP:20260418T094802Z
UID:ScReGeFor/20
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/ScReGeFor/20
 /">Non-Oscillating Trajectories of Vector Fields\, Lecture 4</a>\nby Ferna
 ndo Sanz (Universidad de Valladolid) as part of School of Real Geometry in
  Fortaleza - ScReGeFor\n\n\nAbstract\nA very interesting setting where Rea
 l Analytic Geometry interacts with Model Theory concerns the asymptotic be
 haviour of trajectories of real analytic vector fields at singular points\
 , either as a single object or as pencils of such objects. Little is known
  is general and\, yet\, there are many partial results and examples about 
 this appealing topic. Fernando Sanz will tell us more about this\, and if 
 times allows will be able to speak of some of his latest results and share
  a few hopes for still open problems.\n
LOCATION:https://researchseminars.org/talk/ScReGeFor/20/
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