Johan Öinert PhD and Reader in Mathematics (På svenska: Teknologie doktor och docent i matematik)
		Professor of Mathematics

• Non-commutative algebra: Crossed products [1] [2] and more generally graded rings [3] [4] [5]. Ore extensions [6].
• Dynamical systems: Minimal dynamical systems and groupoid C*-dynamical systems.
• The interplay between dynamical systems and C*-algebras, and various algebraic constructions.
• Crossed product Banach algebras. (More details here.)

• Icke-kommutativ algebra: Korsprodukter och graderade ringar i största allmänhet. Ore-utvidgningar.
• Dynamiska system: Minimala dynamiska system och gruppoid C*-dynamiska system.
• Samspelet mellan dynamiska system och C*-algebror, och diverse algebraiska konstruktioner.
• Banach-korsprodukter. (Mer detaljer här.)

I am a member of the research group in Algebra and Geometry at Blekinge Institute of Technology . In the past, I have been a member of the research groups in Non-commutative Geometry and Applications respectively Algebra, at Lund University (2012-2014), the research group in Non-commutative Geometry within the Centre for Symmetry and Deformation at the University of Copenhagen (2010-2012), the research group in Non-commutative Geometry and Applications at Lund University (2008-2010) and the research group in Algebra and Geometry at the University of Antwerp (2006-2008).

My favourite open problems

1. Kaplansky's idempotent/zero-divisor/unit conjecture for group rings (A counterexample to the unit conjecture was provided by Gardam in 2021. See arXiv.)
2. The Kadison-Kaplansky conjecture
3. The Baum-Connes conjecture
4. The Goldbach conjecture
5. The Kadison-Singer problem, Solved in 2013 by Marcus, Spielman and Srivastava!!!, arXiv:1306.3969 [math.CO]
6. Köthe's conjecture
7. The Riemann hypothesis

Students, collaborators, genealogy etc.

• Dr. Viviane M. Beuter
• Dr. Daniel Gonçalves
• Dr. Jonas T. Hartwig /
• Dr. Mai Hoang Bien
• Tekn. Lic. Daniel Lännström
• Dr. Patrik Nystedt (formerly known as Lundström)
• Dr. Héctor E. Pinedo Tapia
• Dr. Johan Richter
• Dr. Danilo Royer
• Dr. Sergei Silvestrov /
• Dr. Theodora Theohari-Apostolidi
• Dr. Harilaos Vavatsoulas
• and Dr. Stefan Wagner .

• I have been assistant supervisor for Johan Richter , who was a PhD student at Lund University. Johan defended his licentiate thesis on October 5, 2012, and his doctoral thesis on September 29, 2014. His PhD thesis, entitled ''Algebraic Properties of Ore Extensions and Their Commutative Subrings'', can be found here.

• I have been a mentor for Sanaz Pooya , who is a PhD student at Ferdowsi University of Mashhad, Iran, and who was visiting Lund University for 10 months (September 2013-June 2014) as a guest PhD student with an Erasmus Mundus (SALAM) scholarship.

• I have supervised Bartosz Malman , who presented his master's thesis, entitled ''Zero-divisors and idempotents in group rings'', on August 28, 2014. The thesis can be downloaded from here.

• I have been a mentor for Mai Hoang Bien , who was a postdoctoral researcher at Blekinge Institute of Technology during 10 months (January 2016-October 2016).

• I am a mentor for Stefan Wagner , who is a postdoctoral researcher at Blekinge Institute of Technology since June 2017.

• I am supervising Daniel Lännström , who is a PhD student at Blekinge Institute of Technology. Daniel defended his licentiate thesis, entitled "The structure of epsilon-strongly graded rings with applications to Leavitt path algebras and Cuntz-Pimsner rings", on May 15, 2019. It can be found here. He has authored three interesting research papers which you can find here, here, and here.

• I have been a mentor for Samaneh Baghdari , who is a PhD student at Isfahan University of Technology, Iran, and who was visiting Blekinge Institute of Technology for 6 months (September 2018-February 2019) as a guest PhD student.

In the autumn of 2012, I participated in the Leavitt Path Algebra Seminar at the Centre for Symmetry and Deformation, University of Copenhagen.

People that I like to keep track of:
Gergely Berczi, Viola Bruni, Vladimir Dotsenko, Alex Engström , Ghislain Fourier, Magnus Goffeng, Isar Goyvaerts, Jonas Hartwig, Daniel Larsson, Javier Lopez Pena, Douglas Lundholm, Samuel Lundqvist, Ehud Meir, Tomas Persson, Anne Pichereau, Artur Ruuge, Karl Rökaeus, Isar Stubbe, Christian Svensson, Jacob Sznajdman, Bogdan Toader, Fred Van Oystaeyen, Qimh Xantcha.

Genealogy of my mathematical ancestors (i.e. supervisor, supervisor's supervisor etc.) from The Mathematics Genealogy Project
Carl Fabian Björling
Anders Wiman	Erik Holmgren
Arne Beurling	Torsten Carleman
Lennart Carleson	Åke Pleijel
Hans Wallin	Jaak Peetre
Sergei D. Silvestrov	Gunnar Sparr
Me

(DS=Datorsäkerhet, IE=Industriell ekonomi, MT=Maskinteknik, SP=Spel- och programvaruteknik)

• J. Öinert,
  "Connections between Topological Dynamical Systems and Non-Commutative C*-Algebras", v+102 pp.,
  Master's Theses in Mathematical Sciences 2005:E35,
  ISSN 1404-6342, LUTFMA-3123-2005, Lund University, 2005.

• J. Öinert,
  "Ideals and Maximal Commutative Subrings of Graded Rings", xii+171 pp.,
  Doctoral Theses in Mathematical Sciences 2009:5,
  ISSN 1404-0034, LUTFMA-1038-2009, ISBN 978-91-628-7832-0, Lund University, 2009.
  Errata

1. J. Öinert and S. Silvestrov,
   ''Commutativity and Ideals in Algebraic Crossed Products'',
   Journal of Generalized Lie Theory and Applications, Vol. 2, No. 4, pp. 287-302 (2008)
   

2. J. Öinert and S. Silvestrov,
   ''On a Correspondence Between Ideals and Commutativity in Algebraic Crossed Products'',
   Journal of Generalized Lie Theory and Applications, Vol. 2, No. 3, pp. 216-220 (2008)

3. J. Öinert and S. Silvestrov,
   ''Crossed Product-Like and Pre-Crystalline Graded Rings'',
   Chapter 24 in "Generalized Lie Theory in Mathematics, Physics and Beyond", Silvestrov, S.; Paal, E.; Abramov, V.; Stolin, A. (Eds.), 16pp., Springer (2009) [ publisher's web site ]
   

4. J. Öinert and S. Silvestrov,
   "Commutativity and Ideals in Pre-Crystalline Graded Rings",
   Acta Applicandae Mathematicae, Vol. 108, No. 3, pp. 603-615 (2009) [ publisher's website ]
   

5. J. Öinert, S. Silvestrov, T. Theohari-Apostolidi and H. Vavatsoulas,
   "Commutativity and Ideals in Strongly Graded Rings",
   Acta Applicandae Mathematicae, Vol. 108, No. 3, pp. 585-602 (2009) [ publisher's website ]
   

6. J. Öinert,
   "Simple Group Graded Rings and Maximal Commutativity",
   Contemporary Mathematics (American Mathematical Society), Vol. 503, pp. 159-175 (2009)
   

7. J. Öinert and P. Lundström,
   "Commutativity and Ideals in Category Crossed Products",
   Proceedings of the Estonian Academy of Sciences, Vol. 59, No. 4, pp. 338-346 (2010)

8. J. Öinert and P. Lundström,
   "The Ideal Intersection Property for Groupoid Graded Rings",
   Communications in Algebra, Vol. 40, No. 5, pp. 1860-1871 (2012) [ publisher's website ]

9. J. Öinert and P. Lundström,
   "Miyashita Action in Strongly Groupoid Graded Rings",
   International Electronic Journal of Algebra, Vol. 11, pp. 46-63 (2012)

10. P. Lundström and J. Öinert,
    "Skew category algebras associated with partially defined dynamical systems",
    International Journal of Mathematics, Vol. 23, No. 4, pp. 16 (2012) [ publisher's website ]

11. J. T. Hartwig and J. Öinert,
    "Simplicity and maximal commutative subalgebras of twisted generalized Weyl algebras",
    Journal of Algebra, Vol. 373, 312-339 (2013) [ publisher's website ]

12. J. Öinert, J. Richter and S. Silvestrov,
    "Maximal commutative subrings and simplicity of Ore extensions",
    Journal of Algebra and Its Applications, Vol. 12, No. 4, 1250192, 16 pp. (2013) [ publisher's website ]

13. J. Öinert,
    "Simplicity of skew group rings of abelian groups",
    Communications in Algebra, Vol. 42, No. 2, 831-841 (2014). [ publisher's website ]

14. P. Nystedt and J. Öinert,
    "Simple skew category algebras associated with minimal partially defined dynamical systems",
    Discrete and Continuous Dynamical Systems - Series A (DCDS-A), Vol. 33, No. 9, 4157-4171 (2013) [ publisher's website ]

15. P. Nystedt and J. Öinert,
    "Simple rings and degree maps",
    Journal of Algebra, Vol. 401, 201-219 (2014) [ publisher's website ]

16. D. Gonçalves, J. Öinert and D. Royer,
    "Simplicity of partial skew group rings with applications to Leavitt path algebras and topological dynamics",
    Journal of Algebra, Vol. 420, 201-216 (2014) [ publisher's website ]

17. P. Nystedt and J. Öinert,
    "Simple semigroup graded rings",
    Journal of Algebra and Its Applications, Vol. 14, No. 7, 1550102, 10 pp. (2015) [ publisher's website ]

18. P. Nystedt and J. Öinert,
    "Outer partial actions and partial skew group rings",
    Canadian Journal of Mathematics, Vol. 67, No. 5, 1144-1160 (2015) [ publisher's website ]
    [ Preprint available @ arXiv ]

19. P. Nystedt, J. Öinert and J. Richter,
    "Non-associative Ore Extensions",
    Israel Journal of Mathematics, Vol. 224, No. 1, 263-292 (2018) [ publisher's website ]
    [ Preprint available @ arXiv ]

20. Mai Hoang B. and J. Öinert,
    "Quasi-duo differential polynomial rings",
    Journal of Algebra and Its Applications, Vol. 17, No. 4, 11 pp. (2018) [ publisher's website ]
    [ Preprint available @ arXiv ]

21. J. Öinert,
    "Bimodules in group graded rings",
    Algebras and Representation Theory, Vol. 20, No. 6, 1483-1494 (2017) [ publisher's website ]
    [ Preprint available @ arXiv ]

22. P. Nystedt, J. Öinert and H. Pinedo,
    "Artinian and noetherian partial skew groupoid rings",
    Journal of Algebra, Vol. 503, 433-452 (2018) [ publisher's website ]
    [ Preprint available @ arXiv ]

23. P. Nystedt, J. Öinert and H. Pinedo,
    "Epsilon-strongly graded rings, separability and semisimplicity",
    Journal of Algebra, Vol. 514, 1-24 (2018) [ publisher's website ]
    [ Preprint available @ arXiv ]

24. V. Beuter, D. Gonçalves, J. Öinert and D. Royer,
    "Simplicity of skew inverse semigroup rings with applications to Steinberg algebras and topological dynamics",
    Forum Mathematicum, Vol. 31, No. 3, 543-562 (2019) [ publisher's website ]
    [ Preprint available @ arXiv ]

25. P. Nystedt, J. Öinert and H. Pinedo,
    "Epsilon-strongly groupoid-graded rings, the Picard inverse category and cohomology",
    Glasgow Mathematical Journal, Vol. 62, 233-259 (2020)
    [ Preprint available @ arXiv ]

26. P. Nystedt, J. Öinert and J. Richter,
    "Simplicity of Ore monoid rings",
    Journal of Algebra, Vol. 530, 69-85 (2019)
    [ Preprint available @ arXiv ]

27. P. Nystedt and J. Öinert,
    "Group gradations on Leavitt path algebras",
    Journal of Algebra and Its Applications, Vol. 19, No. 9, 16 pp. (2020)
    [ Preprint available @ arXiv ]

28. P. Nystedt and J. Öinert,
    "Simple graded rings, non-associative crossed products and Cayley-Dickson doublings",
    Journal of Algebra and Its Applications, Vol. 19, No. 12, 22 pp. (2020)
    [ Preprint available @ arXiv ]

29. P. Nystedt and J. Öinert,
    "Strongly graded Leavitt path algebras",
    To appear in Journal of Algebra and Its Applications.
    [ Preprint available @ arXiv ]

Publications on mathematics education

30. J. Öinert,
    "Planning and implementing mathematics lectures for first-year university students - 30 tips and tricks",
    Chapter 1 in "Improving University Science Teaching and Learning - Pedagogical Projects 2012", Vol. 5, No. 1, Ulriksen, L; Sølberg, J; Wase Hansen, H. (Eds.), pp. 3-17, Department of Science Education, University of Copenhagen (2013)

Preprints

31. J. Öinert and S. Wagner,
    "Complex group rings of group extensions".
    [ Preprint available @ arXiv ]

32. J. Öinert,
    "Units, zero-divisors and idempotents in rings graded by torsion-free groups", submitted.
    [ Preprint available @ arXiv ]

33. D. Lännström, P. Lundström, J. Öinert and S. Wagner,
    "Prime group graded rings with applications to partial crossed products and Leavitt path algebras", submitted.
    [ Preprint available @ arXiv ]

more coming soon...

Partial lists of my articles can be found on the arXiv, the Zentralblatt MATH and the MathSciNet. Google scholar keeps track of citations of my articles.

1. 3rd Øresund Symposium in Non-commutative Analysis and Non-commutative Geometry,
   January 30, 2004, Lund, Sweden

2. Erasmus Intensive Program in Geometric and Algebraic Methods in Physics and Applications,
   September 4-15, 2005, Antwerp, Belgium

3. Lie Days in Martina Franca, "Flags, Quivers and Invariant Theory in Lie Representation Theory",
   May 22-27, 2006, Martina Franca (Taranto), Italy

4. Socrates Intensive Program in Geometric and Algebraic Methods in Physics and Applications,
   September 4-18, 2006, Antwerp, Belgium

5. International Congress: New Techniques in Hopf Algebras and Graded Ring Theory,
   September 19-23, 2006, Brussels, Belgium

6. Algebra, Geometry & Mathematical Physics, Baltic-Nordic Network Workshop,
   October 12-14, 2006, Lund, Sweden (Gave a talk.)

7. Operator Methods in Fractal Analysis, Wavelets and Dynamical Systems,
   December 2-7, 2006, Banff, Canada (Gave a talk.)

8. Algebraic and Geometric Representation Theory (AGLT),
   Århus, Denmark, June 25-29, 2007

9. Socrates Intensive Program in Geometric & Algebraic Methods with Applications in Physics,
   Antwerpen, Belgium, August 27-September 9, 2007

10. International Conference on Noncommutative Rings and Geometry in Honour of the 60th Birthday of Freddy Van Oystaeyen,
    Almeria, Spain, September 18-23, 2007

11. Workshop on Interpolation Theory,
    Lund, Sweden, October 8, 2007 (Gave a talk.)

12. Algebra, Geometry & Mathematical Physics, Baltic-Nordic Network Workshop,
    Göteborg, Sweden, October 11-13, 2007 (Gave a talk.)

13. Svenska Matematikersamfundets Höstmöte,
    Växjö, Sweden, November 30-December 1, 2007

14. LieGrits Workshop,
    Oxford, UK, January 3-9, 2008

15. EMS Joint Mathematical Weekend,
    Copenhagen, Denmark, February 29-March 2, 2008

16. 5th Øresund Symposium on Non-commutative Analysis and Non-commutative Geometry,
    Copenhagen, Denmark, April 10, 2008 (Gave a talk.)

17. The Tribute Workshop in Honour of Professor Gunnar Sparr,
    Lund, Sweden, May 8-9, 2008

18. Summer School: 'Symbolic Dynamics and Homeomorphisms of the Cantor Set',
    Copenhagen, Denmark, June 23-27, 2008

19. 5th European Congress of Mathematics,
    Amsterdam, The Netherlands, July 14-18, 2008

20. Operator Structures and Dynamical Systems,
    Lorentz Center, Leiden, The Netherlands, July 21-25, 2008 (Gave a talk.)

21. Algebra, Geometry & Mathematical Physics, Baltic-Nordic Network Workshop,
    Tartu, Estonia, October 9-11, 2008 (Gave a talk.)

22. Nordic-Öresund workshop: INANGA, "Inequalities, Interpolation, Non-commutative Analysis, Non-commutative Geometry and Applications",
    Lund, Sweden, November 17-18, 2008 (Gave a talk.)

23. Svenska Matematikersamfundets Höstmöte,
    Linköping, Sweden, November 28-29, 2008 (Gave a talk.)

24. Socrates Intensive Program in Geometric & Algebraic Methods with Applications in Physics,
    Antwerpen, Belgium, July 6-19, 2009

25. PhD thesis defense,
    Lund, Sweden, August 17, 2009
    [The thesis may be downloaded here!]

26. Topics in Mathematical Physics and Operator Algebra,
    September 7, 2009, Copenhagen, Denmark (Gave a talk.)

27. Master Class on Von Neumann Algebras and Group Actions,
    January 25-29, 2010, Copenhagen, Denmark

28. Workshop on Von Neumann Algebras and Group Actions,
    February 1-5, 2010, Copenhagen, Denmark

29. NestFest - Conference in Honor of Ryszard Nest's 60th Birthday,
    September 2-5, 2010, Copenhagen, Denmark

30. Intensive Program on Interpolation and Non-commutative Integration,
    September 30-October 5, 2010, Lund, Sweden

31. Operator Algebras and Representation Theory: Frames, Wavelets and Fractals,
    October 8-10, 2010, Banff, Canada

32. Algebra, Geometry & Mathematical Physics, Baltic-Nordic Network Workshop,
    October 25-31, 2010, Tjärnö, Sweden (Gave a talk.)

33. Operator Algebras and Representation Theory: Frames, Wavelets and Fractals,
    March 27-April 2, 2011, Oberwolfach, Germany

34. Joint Oslo-Trondheim operator algebra seminar,
    May 30-31, 2011, Trondheim, Norway (Gave a talk.)

35. Hopf algebras and tensor categories,
    July 4-8, 2011, Almeria, Spain

36. NordForsk Network Junior Workshop: Operator algebras and dynamical systems,
    September 14-17, 2011, Copenhagen, Denmark

37. Workshop in honor of Kirchberg's 65th birthday,
    November 10-13, 2011, Copenhagen, Denmark

38. Master Class on The Nuclear Dimension of C*-algebras,
    November 14-18, 2011, Copenhagen, Denmark

39. Workshop: Matematiken i civilingenjörsutbildningarna - Ett seminarium tillägnat Lars-Christer Böiers i samband med hans pensionering,
    November 16, 2011, Lund, Sweden

40. NordForsk Network Closing Conference: Operator algebras and dynamical systems,
    May 15-20, 2012, Gjógv, Faroe Islands (Gave a talk.)

41. Mini-workshop: Commutative subalgebras, ideals and actions
    July 23-24, 2012, Lund, Sweden (Gave a talk.)

42. 26th Nordic and 1st European-Nordic Congress of Mathematicians (Dedicated to the memory of Lars Hörmander)
    June 10-13, 2013, Lund, Sweden (Gave a talk.)

43. Banach Algebras and Applications,
    July 29 - August 4, 2013, Gothenburg, Sweden

44. Masterclass on Ergodic Theory and von Neumann algebras,
    October 14-18, 2013, Copenhagen, Denmark

45. Öresundsdagen om grundkurser i matematik på universitet och högskolor,
    October 23, 2013, Lund, Sweden

46. Docentföreläsning, PDF coming soon.
    December 12, 2013, Lund, Sweden

47. Análise funcional geométrica e ações de grupos,
    February 19-21, 2014, Florianópolis, Brazil (Gave a talk.)

48. The Renaissance Combinatorics Seminar,
    April 29, 2014, Helsinki, Finland (Gave a talk.)

49. The 8th Øresund symposium on non-commutative analysis and non-commutative geometry,
    May 15, 2014, Lund, Sweden

50. Den 12:e Sydostkonferensen om matematik,
    August 25, 2015, Karlskrona, Sweden (Gave a talk.)

51. The 2nd Workshop on Dynamics, Numeration and Tilings (FloripaDynSys II),
    December 11-12, 2015, Florianópolis, Brazil (Gave a talk.)

52. Brauer groups, Hopf algebras and monoidal categories, in honour of Stef Caenepeel on the occasion of his 60th birthday,
    May 23-27, 2016, Turin, Italy

53. Kleindagarna @ Institute Mittag-Leffler,
    June 10-12, 2016, Stockholm, Sweden (Gave a talk.)

54. Den 13:e Sydostkonferensen i matematik,
    August 25, 2016, Växjö, Sweden

55. The MAM seminar,
    October 26, 2016, Västerås, Sweden (Gave a talk.)

56. The joint UCL-ULB-VUB seminar on quantum groups, Hopf algebras and monoidal categories,
    February 20, 2017, Louvain-la-Neuve, Belgium (Gave a talk.)

57. The 3rd Workshop on Dynamics, Numeration, Tilings and Graph Algebras (FloripaDynSys III),
    March 20-24, 2017, Florianópolis, Brazil (Gave a talk.)

58. Installationsföreläsning (Eng: Inaugural lecture),
    May 18, 2017, Karlskrona, Sweden

59. Den 14:e Sydostkonferensen i matematik,
    August 22, 2017, Karlskrona, Sweden (Gave a talk.)

60. International Conference on Stochastic Processes and Algebraic Structures, in honour of Dmitrii S. Silvestrov on the occasion of his 70th birthday,
    October 4-6, 2017, Västerås and Stockholm, Sweden (Gave a talk.)

61. Den 15:e Sydostkonferensen i matematik,
    August 28, 2018, Växjö, Sweden (Gave a talk.)

62. The 1st SNAG meeting,
    September 27-28, 2018, Linköping, Sweden (Gave a talk.)

63. Den 2:a Öresundsdagen om grundkurser i matematik på universitet och högskolor,
    October 31, 2018, Copenhagen, Denmark

64. Conference: SYM 10 Years Old,
    June 24-28, 2019, Copenhagen, Denmark

65. Den 16:e Sydostkonferensen i matematik,
    August 30, 2019, Karlskrona, Sweden (Gave a talk.)

66. The 2nd SNAG meeting,
    October 17-18, 2019, Karlskrona, Sweden (Gave a talk.)

67. Richard Kadison and his mathematical legacy - A memorial conference,
    November 29-30, 2019, Copenhagen, Denmark

68. Den 17:e Sydostkonferensen i matematik,
    August 25, 2020, Online

69. The 3rd SNAG meeting,
    September 24-25, 2020, Online

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