jean pradines - Academia.edu (original) (raw)

Papers by jean pradines

arXiv (Cornell University), Nov 13, 2007

Starting with some motivating examples (classsical atlases for a manifold, space of leaves of a f... more Starting with some motivating examples (classsical atlases for a manifold, space of leaves of a foliation, group orbits), we propose to view a Lie groupoid as a generalized atlas for the "virtual structure" of its orbit space, the equivalence between atlases being here the smooth Morita equivalence. This "structure" keeps memory of the isotropy groups and of the smoothness as well. To take the smoothness into account, we claim that we can go very far by retaining just a few formal properties of embeddings and surmersions, yielding a very polymorphous unifying theory. We suggest further developments.

L'etude des systemes completement integrables en geometrie ou en mecanique conduit a introdui... more L'etude des systemes completement integrables en geometrie ou en mecanique conduit a introduire, sur l'espace des feuilles, des orbites, ou des mouvements, une structure plus riche qu'une topologie, mais en general plus faible qu'une structure de variete reguliere. Plusieurs structures ont ete considerees par differents auteurs. On compare ces structures

arXiv: Differential Geometry, Nov 10, 2007

The geometric understanding of Cartan connections led Charles Ehresmann from the Erlangen program... more The geometric understanding of Cartan connections led Charles Ehresmann from the Erlangen program of (abstract) transformation groups to the enlarged program of Lie groupoid actions, via the basic concept of structural groupoid acting through the fibres of a (smooth) principal fibre bundle or of its associated bundles, and the basic examples stemming from the manifold of jets (fibred by its source or target projections). We show that the remarkable relation arising between the actions of the structural group and the structural groupoid (which are mutually determined by one another and commuting) may be viewed as a very special (unsymmetrical!) instance of a general fully symmetric notion of "conjugation between principal actions" and between "associated actions", encapsulated in a nice "butterfly diagram". In this prospect, the role of the local triviality looks more incidental, and may be withdrawn, allowing to encompass and bring together much more general situations. We describe various examples illustrating the ubiquity of this concept in Differential Geometry, and the way it unifies miscellaneous aspects of fibre bundles and foliations.

Sağlıklı bir toplum ve ekonominin oluşması etik ve sosyal sorumluluk bilinci ile paraleldir. Dola... more Sağlıklı bir toplum ve ekonominin oluşması etik ve sosyal sorumluluk bilinci ile paraleldir. Dolayısıyla işletmeler kadar tüketicilere de görev düşmektedir. Buradan hareketle bu çalışmada, tüketicilerin tüketici etiği konusundaki algılamaları ölçülmüş ve kullanmış oldukları markayı ne denli tanıdıkları belirlenmeye çalışılmıştır. Böylece, tüketicilerin tüketici etiği temel alınarak hangi davranışları kabul edip etmediği tespit edilmeye çalışılmıştır. Bu çalışmada, marka kişilik boyutları ve etik algılar arasındaki ilişkiler incelenmektedir. Bu kapsamda anket formu ile bilgiler toplanmış ve bireyler, demografik özellikleri baz alınarak tüketici etiğinin algılanışı açısından değerlendirilmiş ve tüketici etiğinin oluşumuna yön veren faktörler belirlenmeye çalışılmıştır. Bulgular neticesinde, cevaplayıcıların etik ihlali bilmeden önce markanın yansıttığı kişilik özelliklerinin olumlu olduğu sonucuna ulaşılmıştır. Ancak, etik ihlalin söz konusu olduğu olaylar karşısında (hayvanlar üzerinde test, yaş, ırk, cinsiyet ayrımı, kötü üretim koşulları vb.) üzüntü ve kızgınlık duydukları fakat etik ihlal sonrası markanın yansıttığı kişiliğin cevaplayıcı gözünde değişmediği görülmüştür.

This is a survey concerning the relationship between Lie Groupoids (and their morphisms) and sing... more This is a survey concerning the relationship between Lie Groupoids (and their morphisms) and singular foliations in the sense of Sussmann-Stefan (considered from a purely geometrical point of view). We focus on the interaction between the algebraic and differentiable structures underlying Lie groupoids, and between groups and graphs of equivalence relations, regarded as two basic degeneracies for groupoids. Historical remarks, motivations and examples are developed in five appendices.

Comptes Rendus De L Academie Des Sciences Series I Mathematics, 1984

Central European Journal of Mathematics, 2004

Starting with some motivating examples (classical atlases for a manifold, space of leaves of a fo... more Starting with some motivating examples (classical atlases for a manifold, space of leaves of a foliation, group orbits), we propose to view a Lie groupoid as a generalized atlas for the “virtual structure” of its orbit space, the equivalence between atlases being here the smooth Morita equivalence. This “structure” keeps memory of the isotropy groups and of the smoothness as well. To take the smoothness into account, we claim that we can go very far by retaining just a few formal properties of embeddings and surmersions, yielding a very polymorphous unifying theory. We suggest further developments.

Cahiers de Topologie et Géométrie Différentielle Catégoriques, 1985

© Andrée C. Ehresmann et les auteurs, 1985, tous droits réservés. L’accès aux archives de la revu... more © Andrée C. Ehresmann et les auteurs, 1985, tous droits réservés. L’accès aux archives de la revue « Cahiers de topologie et géométrie différentielle catégoriques » implique l’accord avec les conditions générales d’utilisation (http://www.numdam.org/legal.php). Toute utilisation commerciale ou impression systématique est constitutive d’une infraction pénale. Toute copie ou impression de ce fichier doit contenir la présente mention de copyright.

The geometric understanding of Cartan connections led Charles Ehresmann from the Erlangen program... more The geometric understanding of Cartan connections led Charles Ehresmann from the Erlangen program of (abstract) transformation groups to the enlarged program of Lie groupoid actions, via the basic concept of structural groupoid acting through the fibres of a (smooth) principal fibre bundle or of its associated bundles, and the basic examples stemming from the manifold of jets (fibred by its source or target projections). We show that the remarkable relation arising between the actions of the structural group and the structural groupoid (which are mutually determined by one another and commuting) may be viewed as a very special (unsymmetrical!) instance of a general fully symmetric notion of “conjugation between principal actions ” and between “associated actions”, encapsulated in a nice “butterfly diagram”. In this prospect, the role of the local triviality looks more incidental, and may be withdrawn, allowing to encompass and bring together much more general situations. We describe...

arXiv: Geometric Topology, 1989

Reprint of a 1989 paper including minor corrections of misprints. Added comments (11 pages) about... more Reprint of a 1989 paper including minor corrections of misprints. Added comments (11 pages) about later related papers in the literature concerning comparison of Gabriel-Zisman calculus of (right) fractions and the use of generalized morphims in the sense of Haefliger-Skandalis-Hilsum for inverting differentiable equivalences between Lie groupoids.

Comptes Rendus De L Academie Des Sciences Series I Mathematics, 1985

Comptes Rendus De L Academie Des Sciences Series I Mathematics, 1989

Actas De Las Iv Jornadas Matematicas Luso Espanolas Jaca Mayo 1977 Vol 2 1980 Isbn 84 600 1920 9 Pags 365 371, 1980

Comptes Rendus De L Academie Des Sciences Series I Mathematics, 1986

Geometry and Topology of Manifolds, 2007

arXiv (Cornell University), Nov 13, 2007

Starting with some motivating examples (classsical atlases for a manifold, space of leaves of a f... more Starting with some motivating examples (classsical atlases for a manifold, space of leaves of a foliation, group orbits), we propose to view a Lie groupoid as a generalized atlas for the "virtual structure" of its orbit space, the equivalence between atlases being here the smooth Morita equivalence. This "structure" keeps memory of the isotropy groups and of the smoothness as well. To take the smoothness into account, we claim that we can go very far by retaining just a few formal properties of embeddings and surmersions, yielding a very polymorphous unifying theory. We suggest further developments.

L'etude des systemes completement integrables en geometrie ou en mecanique conduit a introdui... more L'etude des systemes completement integrables en geometrie ou en mecanique conduit a introduire, sur l'espace des feuilles, des orbites, ou des mouvements, une structure plus riche qu'une topologie, mais en general plus faible qu'une structure de variete reguliere. Plusieurs structures ont ete considerees par differents auteurs. On compare ces structures

arXiv: Differential Geometry, Nov 10, 2007

The geometric understanding of Cartan connections led Charles Ehresmann from the Erlangen program... more The geometric understanding of Cartan connections led Charles Ehresmann from the Erlangen program of (abstract) transformation groups to the enlarged program of Lie groupoid actions, via the basic concept of structural groupoid acting through the fibres of a (smooth) principal fibre bundle or of its associated bundles, and the basic examples stemming from the manifold of jets (fibred by its source or target projections). We show that the remarkable relation arising between the actions of the structural group and the structural groupoid (which are mutually determined by one another and commuting) may be viewed as a very special (unsymmetrical!) instance of a general fully symmetric notion of "conjugation between principal actions" and between "associated actions", encapsulated in a nice "butterfly diagram". In this prospect, the role of the local triviality looks more incidental, and may be withdrawn, allowing to encompass and bring together much more general situations. We describe various examples illustrating the ubiquity of this concept in Differential Geometry, and the way it unifies miscellaneous aspects of fibre bundles and foliations.

Sağlıklı bir toplum ve ekonominin oluşması etik ve sosyal sorumluluk bilinci ile paraleldir. Dola... more Sağlıklı bir toplum ve ekonominin oluşması etik ve sosyal sorumluluk bilinci ile paraleldir. Dolayısıyla işletmeler kadar tüketicilere de görev düşmektedir. Buradan hareketle bu çalışmada, tüketicilerin tüketici etiği konusundaki algılamaları ölçülmüş ve kullanmış oldukları markayı ne denli tanıdıkları belirlenmeye çalışılmıştır. Böylece, tüketicilerin tüketici etiği temel alınarak hangi davranışları kabul edip etmediği tespit edilmeye çalışılmıştır. Bu çalışmada, marka kişilik boyutları ve etik algılar arasındaki ilişkiler incelenmektedir. Bu kapsamda anket formu ile bilgiler toplanmış ve bireyler, demografik özellikleri baz alınarak tüketici etiğinin algılanışı açısından değerlendirilmiş ve tüketici etiğinin oluşumuna yön veren faktörler belirlenmeye çalışılmıştır. Bulgular neticesinde, cevaplayıcıların etik ihlali bilmeden önce markanın yansıttığı kişilik özelliklerinin olumlu olduğu sonucuna ulaşılmıştır. Ancak, etik ihlalin söz konusu olduğu olaylar karşısında (hayvanlar üzerinde test, yaş, ırk, cinsiyet ayrımı, kötü üretim koşulları vb.) üzüntü ve kızgınlık duydukları fakat etik ihlal sonrası markanın yansıttığı kişiliğin cevaplayıcı gözünde değişmediği görülmüştür.

This is a survey concerning the relationship between Lie Groupoids (and their morphisms) and sing... more This is a survey concerning the relationship between Lie Groupoids (and their morphisms) and singular foliations in the sense of Sussmann-Stefan (considered from a purely geometrical point of view). We focus on the interaction between the algebraic and differentiable structures underlying Lie groupoids, and between groups and graphs of equivalence relations, regarded as two basic degeneracies for groupoids. Historical remarks, motivations and examples are developed in five appendices.

Comptes Rendus De L Academie Des Sciences Series I Mathematics, 1984

Central European Journal of Mathematics, 2004

Starting with some motivating examples (classical atlases for a manifold, space of leaves of a fo... more Starting with some motivating examples (classical atlases for a manifold, space of leaves of a foliation, group orbits), we propose to view a Lie groupoid as a generalized atlas for the “virtual structure” of its orbit space, the equivalence between atlases being here the smooth Morita equivalence. This “structure” keeps memory of the isotropy groups and of the smoothness as well. To take the smoothness into account, we claim that we can go very far by retaining just a few formal properties of embeddings and surmersions, yielding a very polymorphous unifying theory. We suggest further developments.

Cahiers de Topologie et Géométrie Différentielle Catégoriques, 1985

© Andrée C. Ehresmann et les auteurs, 1985, tous droits réservés. L’accès aux archives de la revu... more © Andrée C. Ehresmann et les auteurs, 1985, tous droits réservés. L’accès aux archives de la revue « Cahiers de topologie et géométrie différentielle catégoriques » implique l’accord avec les conditions générales d’utilisation (http://www.numdam.org/legal.php). Toute utilisation commerciale ou impression systématique est constitutive d’une infraction pénale. Toute copie ou impression de ce fichier doit contenir la présente mention de copyright.

The geometric understanding of Cartan connections led Charles Ehresmann from the Erlangen program... more The geometric understanding of Cartan connections led Charles Ehresmann from the Erlangen program of (abstract) transformation groups to the enlarged program of Lie groupoid actions, via the basic concept of structural groupoid acting through the fibres of a (smooth) principal fibre bundle or of its associated bundles, and the basic examples stemming from the manifold of jets (fibred by its source or target projections). We show that the remarkable relation arising between the actions of the structural group and the structural groupoid (which are mutually determined by one another and commuting) may be viewed as a very special (unsymmetrical!) instance of a general fully symmetric notion of “conjugation between principal actions ” and between “associated actions”, encapsulated in a nice “butterfly diagram”. In this prospect, the role of the local triviality looks more incidental, and may be withdrawn, allowing to encompass and bring together much more general situations. We describe...

arXiv: Geometric Topology, 1989

Reprint of a 1989 paper including minor corrections of misprints. Added comments (11 pages) about... more Reprint of a 1989 paper including minor corrections of misprints. Added comments (11 pages) about later related papers in the literature concerning comparison of Gabriel-Zisman calculus of (right) fractions and the use of generalized morphims in the sense of Haefliger-Skandalis-Hilsum for inverting differentiable equivalences between Lie groupoids.

Comptes Rendus De L Academie Des Sciences Series I Mathematics, 1985

Comptes Rendus De L Academie Des Sciences Series I Mathematics, 1989

Actas De Las Iv Jornadas Matematicas Luso Espanolas Jaca Mayo 1977 Vol 2 1980 Isbn 84 600 1920 9 Pags 365 371, 1980

Comptes Rendus De L Academie Des Sciences Series I Mathematics, 1986

Geometry and Topology of Manifolds, 2007