Interests

Olof Widlund works primarily on domain decomposition for partial differential equations.

Selected Papers. Of the papers made available here, almost all were further modified prior to final publication.

  1. Petter E. Bjørstad and Olof B. Widlund. ``Iterative Methods for the Solution of Elliptic Problems on Regions Partitioned into Substructures'', SIAM J. Num. Anal., Vol. 23, No. 6, 1986, 1097-1120.

  2. Olof B. Widlund. ``An Extension Theorem for Finite Element Spaces with Three Applications,'' Proceedings of a GAMM Seminar on Numerical Techniques in Continuum Mechanics, held in Kiel, Germany January 17-19, 1986 (Wolfgang Hackbusch and Kristian Witsch, eds), Friedr. Vieweg and Sohn, Braunschweig/Wiesbaden, 1987, 110-122.

  3. Christoph Börgers and Olof B. Widlund. ``On Finite Element Domain Imbedding Methods,'' SIAM J. Numer. Anal., Vol. 27, No. 4, 1990, 963-978.

  4. Christoph Börgers and Olof B. Widlund. ``A Domain Decomposition Laplace Solver for Internal Combustion Engine Modeling,'' SIAM J. Sci. Statist. Comput., Vol. 10, No. 2, 1989, 211-226.

  5. Petter E. Bjørstad and Olof B. Widlund. ``To Overlap or Not to Overlap: A Note on A Domain Decomposition Method for Elliptic Problems,'' August 1988, SIAM J. Sci. Statist. Comput., Vol. 10, No. 5, 1989, 1053-1061.

  6. Barry F. Smith and Olof B. Widlund. ``A Domain Decomposition Algorithm Using a Hierarchical Basis,'' SIAM J. Sci. Statist. Comput., Vol. 11, No. 6, November 1990, 1212-1220.

  7. Maksymilian Dryja and Olof B. Widlund. ``Towards a Unified Theory of Domain Decomposition Algorithms for Elliptic Problems'', in the proceedings of the Third International Symposium on Domain Decomposition Methods for Partial Differential, held in Houston, Texas, March 20-22, 1989. SIAM, 1990.

  8. Daniel B. Szyld and Olof B. Widlund. ``Variational Analysis of Some Conjugate Gradient Methods'', East-West Journal of Numerical Mathematics, Vol. 1, No. 1, 1993, 51-74. Full text of published paper in pdf.

  9. Xiao-Chuan Cai and Olof B. Widlund. ``Domain Decomposition Algorithms for Indefinite Elliptic Problems'', SIAM J. Sci. Statist. Comput., Vol. 13, No. 1, 1992, 243-258.

  10. Xiao-Chuan Cai and Olof B. Widlund. ``Multiplicative Schwarz Algorithms for Some Nonsymmetric and Indefinite Problems'', SIAM J. Numer. Anal., Vol. 30, No. 4, 1993, 936-952.

  11. Maksymilian Dryja and Olof B. Widlund. ``Domain Decomposition Algorithms with Small Overlap'', SIAM J. Sci. Stat. Comput., Vol. 15, No. 3, May 1994, 604-620.

  12. Maksymilian Dryja and Olof B. Widlund. ``Schwarz Methods of Neumann-Neumann Type for Three- Dimensional Elliptic Finite Element Problems'', Comm. Pure Appl. Math., Vol. 48, No. 2, February 1995, 121-155.

  13. Maksymilian Dryja, Barry F. Smith, and Olof B. Widlund. ``Schwarz Analysis of Iterative Substructuring Algorithms for Elliptic Problems in Three Dimensions'', SIAM J. Numer. Anal., Vol. 31, No. 6, December 1994, 1662-1694.

  14. Luca F. Pavarino and Olof B. Widlund. ``A Polylogarithmic Bound for an Iterative Substructuring Method for Spectral Elements in Three Dimensions'', SIAM J. Numer. Anal., Vol. 33, No. 4, August 1996, 1303--1335. Full text in postscript.

  15. Maksymilian Dryja, Marcus Sarkis, and Olof B. Widlund. ``Multilevel Schwarz Methods for Elliptic Problems with Discontinuous Coefficients in Three Dimensions'', Numer. Math., Vol. 72, 1996, 313-348.

  16. Luca F. Pavarino and Olof B. Widlund. ``Iterative Substructuring Methods for Spectral Elements: Problems in Three Dimensions Based on Numerical Quadrature'', International Journal on Computers and Mathematics with Applications, Vol. 33, No. 1/2, January 1997, 193--209.

  17. Mario Casarin and Olof B. Widlund. ``A Hierarchical Preconditioner for the Mortar Finite Element Method'', ETNA, Vol. 4, June 1996, pp. 75-88. Full text in postscript.

  18. Olof B. Widlund. ``Preconditioners for Spectral and Mortar Finite Element Methods'', Proceedings of the Eighth International Conference of Domain Decomposition Methods, held in Beijing, PRC, May 15-19, 1995. Wiley-Interscience, 1996, Strasbourg, France.

  19. Yves Achdou, Yvon Maday, and Olof B. Widlund. ``Iterative Substructuring Preconditioners for Mortar Element Methods in Two Dimensions,'' SIAM J. Numer. Anal., Vol. 36, No. 2, 1999, 551--580. Full text in postscript.

  20. Luca F. Pavarino and Olof B. Widlund. ``Iterative Substructuring Methods for Spectral Element Discretizations of Elliptic Systems. I: Compressible Linear Elasticity'', SIAM J. Numer. Anal., Vol. 37, No. 2, 1999, 353--374. Full text in postscript.

  21. Xiao-Chuan Cai, Mario A. Casarin, Jr., Frank W. Elliot, Jr. and Olof B. Widlund. ``Overlapping Schwarz Algorithms for Solving Helmholtz's Equation'', Domain Decomposition Methods 10, AMS Contemporary Mathematics Vol. 218, pp. 391-399, 1998. Full text in postscript.

  22. Luca F. Pavarino and Olof B. Widlund. ``Iterative Substructuring Methods for Spectral Element Discretizations of Elliptic Systems. II: Mixed Methods for Linear Elasticity and Stokes Flow '', SIAM J. Numer. Anal., Vol. 37, No. 2, 1999, 375--402. Full text in postscript.

  23. Andrea Toselli, Barbara I. Wohlmuth, and Olof B. Widlund. ``An Iterative Substructuring Method for Maxwell's Equations in Two Dimensions'', Math. Comp., Vol. 70, No. 235, July 2001, 935--949. Full text in postscript.

  24. Barbara I. Wohlmuth, Andrea Toselli, and Olof B. Widlund. `Iterative Substructuring Method for Raviart-Thomas Vector Fields in Three Dimensions'', SIAM J. Numer. Anal., Vol. 37, No. 5, May 2000, 1657--1676. Full text in postscript.

  25. Axel Klawonn and Olof B. Widlund. ``A domain decomposition method with Lagrange multipliers for linear elasticity'', SIAM J. Sci. Comput., Vol. 22, No. 4, October, 2000, 1199-1219. Full text in postscript.

  26. Axel Klawonn and Olof B. Widlund. ``FETI and Neumann-Neumann Iterative Substructuring Methods: Connections and New Results'', Comm. Pure Appl. Math., Vol. 54, No. 1, January 2001, 57--90. Full text in postscript.

  27. Luca F. Pavarino and Olof B. Widlund. ``Balancing Neumann-Neumann methods for incompressible Stokes equations'', Comm. Pure Appl. Math., Vol. 55, No. 3, March 2002, 302--335. TR , in postscript.

  28. Axel Klawonn, Olof B. Widlund, and Maksymilian Dryja. ``Dual-Primal FETI Methods for Three-dimensional Elliptic Problems with Heterogeneous Coefficients'', SIAM J. Numer. Anal., Vol. 40, No. 1, April 2002, 159--179. TR , in postscript.

  29. Paulo Goldfeld, Luca F. Pavarino, and Olof B. Widlund. ``Balancing Neumann-Neumann Preconditioners for Mixed Approximations of Heterogeneous Problems in Linear Elasticity'', Numer. Math., Vol. 95, No. 2, 2003, 283--324. TR , in postscript.

  30. Axel Klawonn, Oliver Rheinbach, and Olof B. Widlund. ``Some Computational Results for FETI-DP Methods in 3D'', in Proceedings of the 15th International Conference on Domain Decomposition Methods. Full text in pdf.

  31. Axel Klawonn and Olof B. Widlund. ``Selecting Constraints in FETI-DP for Elasticity in Three Dimensions'', in Proceedings of the 15th International Conference on Domain Decomposition Methods. Full text in pdf.

  32. Axel Klawonn and Olof B. Widlund. ``Dual-Primal FETI Methods for Linear Elasticity'', TR2004-855, September 2004. Comm. Pure Appl. Math., Vol. 59, #11, November 2006, 1523--1572, (revised). Full text in pdf.

  33. Jing Li and Olof B. Widlund. ``FETI--DP, BDDC, and Block Cholesky Methods'', TR2004-857, December 2004. Internat. J. Numer. Methods Engrg., Vol. 66, #2, 2006, 250--271. Full text in pdf.

  34. Jing Li and Olof B. Widlund. ``BDDC Algorithms for Incompressible Stokes Equations'', TR2004-861, April 2005. SIAM J. Numer. Anal., Vol. 44, #6, 2006, 2432--2455. Full text in pdf.

  35. Hyea Hyun Kim and Olof B. Widlund. ``Two-Level Schwarz Algorithms, Using Overlapping Subdomains, for Mortar Finite Element Methods'' TR2005--870, July 2005. SIAM J. Numer. Anal. Vol. 44, # 4, 2006, 1514--1534. Full text in pdf.

  36. Jing Li and Olof B. Widlund. ``On the Use of Inexact Subdomain Solvers for BDDC Algorithms'' TR2005--871, July 2005. Comput. Methods Appl. Mech. Engrg. Vol. 196, #8, 2007, 1415--1428. Full text in pdf.

  37. Hyea Hyun Kim, Maksymilian Dryja, and Olof B. Widlund ``A BDDC Algorithm for Problems with Mortar Discretization Using a Transformation of Basis''. SIAM J. Numer. Anal. Vol. 47, #1, 2008, 136--157. Full text in pdf.

  38. Clark R. Dohrmann, Axel Klawonn, and Olof B. Widlund. ``Domain Decomposition for Less Regular Subdomains: Overlapping Schwarz in Two Dimensions", March 2007, SIAM J. Numer. Anal., Vol. 46, #4, 2008, 2153--2168. Full text in pdf.

  39. Axel Klawonn, Oliver Rheinbach, and Olof B. Widlund. ``An analysis of a FETI--DP algorithm on irregular subdomains in the plane'', April 2007. SIAM J. Numer. Anal. Vol. 46, #5, 2008, 2484--2504. Full text in pdf.

  40. Clark R. Dohrmann and Olof B. Widlund. ``An Overlapping Schwarz Algorithm for Almost Incompressible Elasticity'', SIAM J. Numer. Anal. 47 #4, 2009, 2897--2923. Full text in pdf.

  41. Olof B. Widlund. ``Accomodating Irregular Subdomains in Domain Decomposition Theory'', May 2008. Proceedings of the 18th International Conference on Domain Decomposition. Full text in pdf.

  42. Olof B. Widlund. ``The Development of Coarse Spaces for Domain Decomposition Algorithms'', May 2008. Proceedings of the 18th International Conference on Domain Decomposition. Full text in pdf.

  43. Clark R. Dohrmann and Olof B. Widlund. `` Hybrid Domain Decomposition Algorithms for Compressible and Almost Incompressible Elasticity'' Internat. J. Numer. Methods Engrg., Vol. 82, 2010, 157--183. Full text of revised manuscript in pdf.

  44. Luca F. Pavarino, Olof B. Widlund, and Stefano Zampini. `` BDDC preconditioners for spectral element discretizations of almost incompressible elasticity in three dimensions'' Full text in pdf. SIAM J. Sci. Comput. 32 #6, 3604--3626, December 21, 2010.

  45. Clark R. Dohrmann and Olof B. Widlund. ``An Iterative Substructuring Algorithm for Two-Dimensional Problems in H(curl)'' Full text in pdf. SIAM J. Numer. Anal. 50, #3, 1004--1028, May 3, 2012.

  46. Eric T. Chung, Hyea Hyun Kim, and Olof B. Widlund. ``Two-Level Overlapping Schwarz Algorithms for a Staggered Discontinuous Galerkin Method'' Full text in pdf. SIAM J. Numer. Anal. 51, #1, 47--67, January 2, 2013.

  47. Clark R. Dohrmann and Olof B. Widlund. ``Some Recent Tools and a BDDC Algorithm for 3D Problems in H(curl)'', Proceedings of the 20th International Conference on Domain Decomposition Methods. Lecture Notes in Computational Science and Engineering, Springer, Vol. 91. Full text in pdf.

  48. Clark R. Dohrmann and Olof B. Widlund. ``An Alternative Coarse Space for Irregular Subdomains and an Overlapping Schwarz Algorithm for Scalar Elliptic Problems in the Plane" Full text in pdf. SIAM J. Numer. Anal. 50, #5, 2522--2537, November 2012.

  49. Duk-Soon Oh, Olof B. Widlund, and Clark R. Dohrmann. ``A BDDC Algorithm for Raviart--Thomas Vector Fields'' Full text in pdf.

  50. Lourenco Beirao da Veiga, Luca F. Pavarino, Simone Scacchi, Olof B. Widlund, and Stefano Zampini. ``Isogeometric BDDC Preconditioners with Deluxe Scaling'' Full text in pdf. SIAM J. Sci. Comput. 36, #3, A1118--A1139, 2014.

  51. Clark R. Dohrmann and Olof B. Widlund. ``A BDDC algorithm with deluxe scaling for three-dimensional H(curl) problems'' Full text in pdf. Appeared electronically in April 2015 in Comm. Pure Appl. Math.

  52. Mingchao Cai, Luca F. Pavarino, and Olof B. Widlund. ``Overlapping Schwarz Methods with a Standard Coarse Space for Almost Incompressible Linear Elasticity'' Full text in pdf. SIAM J. Sci. Comput. 37, #2, A811--A830, 2015.

  53. Lourenco Beirao da Veiga, Luca F. Pavarino, Simone Scacchi, Olof B. Widlund, and Stefano Zampini. ``Adaptive Selection of Primal Constraints for Isogeometric BDDC Deluxe Preconditioners'' Full text in pdf. Technical report 2015-977, December 2015. To appear in SIAM J. Sci. Comput.

  54. Duk-Soon Oh, Olof B. Widlund, Stefano Zampini, and Clark R. Dohrmann. ``BDDC Algorithms with Deluxe Scaling and Adaptive selection of Primal Constraints for Raviart--Thomas Vector Fields'' Full text in pdf. Technical report 2015-978, January 2016. To appear in Math. Comp.

  55. Juan G. Calvo and Olof B. Widlund. ``An adaptive choice of primal constraints for BDDC domain decomposition algorithms'' Electronic Transactions on Numerical Analysis, Vol. 45, 524--544, 2016. URL = "etna.ricam.oeaw.ac.at/vol45.2016/pp524-544.dir/pp524-544.pdf"

  56. Clark R. Dohrmann and Olof B. Widlund. ``On the design of small coarse spaces for domain decomposition algorithms'' Full text in pdf. Technical report 2017-987. January 2017.