Erik Christensen
Associate professor emeritus
Department of Mathematical Sciences
Universitetsparken 5, 2100 København Ø, 04 Matematik E, Building: 04-0-18
- 2024
- Published
Some points of view on Grothendieck's inequalities
Christensen, Erik, 2024, In: Linear Algebra and Its Applications. 691, p. 196-215 20 p.Research output: Contribution to journal › Journal article › Research › peer-review
- Published
Unique matrix factorizations associated to bilinear forms and Schur multipliers
Christensen, Erik, 2024, In: Linear Algebra and Its Applications. 688, p. 215-231Research output: Contribution to journal › Journal article › Research › peer-review
- 2023
- Published
Bilinear forms, Schur multipliers, complete boundedness and duality
Christensen, Erik, 2023, In: Mathematica Scandinavica. 129, 3, p. 543-569Research output: Contribution to journal › Journal article › Research › peer-review
- Published
Minimal Stinespring Representations of Operator Valued Multilinear Maps
Christensen, Erik, 2023, In: Journal of Operator Theory. 89, 2, p. 587-601 15 p.Research output: Contribution to journal › Journal article › Research › peer-review
- 2020
- Published
Decompositions of block schur products
Christensen, Erik, 2020, In: Journal of Operator Theory. 84, 1, p. 139-152Research output: Contribution to journal › Journal article › Research › peer-review
- Published
The block Schur product is a Hadamard product
Christensen, Erik, 2020, In: Mathematica Scandinavica. 126, 3, p. 603-616Research output: Contribution to journal › Journal article › Research › peer-review
- 2019
- Published
On the complete boundedness of the Schur block product
Christensen, Erik, 2019, In: Proceedings of the American Mathematical Society. 147, 2, p. 523-532Research output: Contribution to journal › Journal article › Research › peer-review
- 2017
- Published
Structural properties of close II1 factors
Cameron, J., Christensen, Erik, Sinclair, A. M., Smith, R. R., White, S. & Wiggins, A. D., 2017, In: Münster Journal of Mathematics. 10, 1, p. 19-37Research output: Contribution to journal › Journal article › Research › peer-review
- 2016
- Published
Commutator inequalities via Schur products
Christensen, Erik, 2016, Operator Algebras and Applications: The Abel Symposium 2015. Carlsen, T. M., Larsen, N. S., Neshveyev, S. & Skau, C. (eds.). Springer, p. 127-143 (Abel Symposia, Vol. 12).Research output: Chapter in Book/Report/Conference proceeding › Article in proceedings › Research › peer-review
- Published
Higher weak derivatives and reflexive algebras of operators
Christensen, Erik, 2016, Operator Algebras and Their Applications: A Tribute to Richard V. Kadison. Doran, R. S. & Park, E. (eds.). American Mathematical Society, p. 69-83 (Contemporary Mathematics, Vol. 671).Research output: Chapter in Book/Report/Conference proceeding › Book chapter › Research › peer-review
- Published
On weakly D-differentiable operators
Christensen, Erik, 2016, In: Expositiones Mathematicae. 34, 1, p. 27–42Research output: Contribution to journal › Journal article › Research › peer-review
- 2014
- Published
Kadison-Kastler stable factors
Cameron, J., Christensen, Erik, Sinclair, A. M., Smith, R. R., White, S. A. & Wiggins, A. D., 2014, In: Duke Mathematical Journal. 163, 14, p. 2639-2686 57 p.Research output: Contribution to journal › Journal article › Research › peer-review
- Published
Von Neumann algebras as complemented subspaces of B(H)
Christensen, Erik & Wang, L., 2014, In: International Journal of Mathematics. 25, 9 p., 1450107.Research output: Contribution to journal › Journal article › Research › peer-review
- 2013
- Published
C*-algebras nearly contained in a type I C*-algebra
Christensen, Erik, Sinclair, A. M., White, S. A. & Smith, R. R., Jan 2013, In: Canadian Journal of Mathematics. 65, p. 52-65 14 p.Research output: Contribution to journal › Journal article › Research › peer-review
- Published
A Remark on the Similarity and Perturbation Problems
Cameron, J., Christensen, Erik, Sinclair, A. M., Smith, R. R., White, S. & Wiggins, A. D., 2013, In: Mathematical Reports of the Academy of Science. 35, 2Research output: Contribution to journal › Journal article › Research › peer-review
- 2012
- Published
Perturbations of nuclear C*-algebras.
Christensen, Erik, Sinclair, A. M., White, S., Smith, R. R. & Winter, W., 2012, In: Acta Mathematica. 208, p. 93-150 58 p.Research output: Contribution to journal › Journal article › Research › peer-review
- Published
Spectral triples and the geometry of fractals
Christensen, Erik, Ivan, C. & Schroe, E., 2012, In: Journal of Noncommutative Geometry. 6, p. 249 - 274 26 p.Research output: Contribution to journal › Journal article › Research › peer-review
- Published
Type II1 factors satisfying the spatial isomorphism conjecture.
Cameron, J., Christensen, Erik, Sinclair, A. M., Smith, R. R., White, S. & Wiggins, A. D., 2012, In: Proceedings of the National Academy of Sciences USA (PNAS). 109, 5, p. 20338 - 20343 6 p.Research output: Contribution to journal › Journal article › Research › peer-review
- 2010
- Published
Perturbations of C*-algebraic Invariants
Christensen, Erik, Sinclair, A. M., Smith, R. R. & White, S., 2010, In: Geometric and Functional Analysis. 20, 2, p. 368 - 397 30 p.Research output: Contribution to journal › Journal article › Research › peer-review
- Published
The spatial isomorphism problem for close separable nuclear C*-algebras
Christensen, Erik, Sinclair, A. M., Smith, R. R., White, S. A. & Winter, W., 2010, In: Proceedings of the National Academy of Science of the United States of America. 107, 2, p. 587 - 591 5 p.Research output: Contribution to journal › Journal article › Research › peer-review
- 2009
- Published
Extensions and degeneration of spectral triples
Christensen, Erik & Ivan, C., 2009, In: Communications in Mathematical Physics. 285, 3, p. 925-955 31 p.Research output: Contribution to journal › Journal article › Research › peer-review
- 2008
- Published
Dirac operators and spectral triples for some fractal sets built on curves
Christensen, Erik, Ivan, C. & Lapidus, M. L., 2008, In: Advances in Mathematics. 217, 1, p. 42 - 78 37 p.Research output: Contribution to journal › Journal article › Research › peer-review
- 2007
- Published
Sums of two-dimensional spectral triples
Christensen, Erik & Ivan, C., 2007, In: Mathematica Scandinavica. 100, 1, p. 35-60 26 p.Research output: Contribution to journal › Journal article › Research › peer-review
- 2006
- Published
Spectral triples for AF C*-algebras and metrics on the Cantor set
Christensen, Erik, 2006, In: Journal of Operator Theory. 56, p. 17-46Research output: Contribution to journal › Journal article › Research › peer-review
- 2004
- Published
Metrics on group C*-algebras and a non-commutative Arzelà-Ascoli Theorem
Antonescu, C. & Christensen, Erik, 2004, In: Journal of Functional Analysis. 214, p. 247-259Research output: Contribution to journal › Journal article › Research › peer-review
- 2003
- Published
Hochschild cohomology of factors with property Gamma
Christensen, Erik, Sinclair, A. M. & Smith, R. R., 2003, In: Annals of Mathematics. 158, 2, p. 597-621Research output: Contribution to journal › Journal article › Research › peer-review
- Published
On some problems studied by R.V. Kadison
Christensen, Erik, 2003, In: Acta Mathematica Sinica. English series. 19, p. 523-534Research output: Contribution to journal › Journal article › Research › peer-review
- Published
Property Gamma factors and the Hochschild cohomology problem
Christensen, Erik, Pop, F., Sinclair, A. M. & Smith, R. R., 2003, In: Proceedings of the National Academy of Science of the United States of America. 100, p. 3865-3869Research output: Contribution to journal › Journal article › Research › peer-review
- 2001
- Published
Finite von Neumann algebra factors with property Gamma
Christensen, Erik, 2001, In: Journal of Functional Analysis. 186, p. 366-380Research output: Contribution to journal › Journal article › Research › peer-review
- Published
- 1998
- Published
On invertibility preserving linear mappings, simultaneous triangularization and Property L.
Christensen, Erik, 1998, In: Linear Algebra and Its Applications. 301, p. 153-170Research output: Contribution to journal › Journal article › Research › peer-review
- 1997
- Published
Two generalizations of the Gleason-Kahane-Z̀elazko theorem
Christensen, Erik, Jan 1997, In: Pacific Journal of Mathematics. 177, 1, p. 27-32 6 p.Research output: Contribution to journal › Journal article › Research › peer-review
- Published
A cohomological characterization of approximately finite dimension von Neumann algebras
Christensen, Erik, 1997, Operator Algebras and quantum field theory. Rom: International Press, p. 323-328Research output: Chapter in Book/Report/Conference proceeding › Book chapter › Research
- Published
On the cohomology groups of cerain finite von Neumann algebras
Christensen, Erik, Pop, F. & Sinclair, A. M., 1997, In: Mathematische Annalen. 307, p. 71-92Research output: Contribution to journal › Journal article › Research › peer-review
- 1995
- Published
Module mappings into von Neumann algebras and injectivity
Christensen, Erik & Sinclair, A. M., 1995, In: Proceedings of the London Mathematical Society. 71, p. 618-640Research output: Contribution to journal › Journal article › Research › peer-review
- 1994
- Published
On von Neumann Algebras which are complemented Subspaces of B(H)
Christensen, Erik & Sinclair, A. M., 1994, In: Journal of Functional Analysis. 122, p. 91-102Research output: Contribution to journal › Journal article › Research › peer-review
- Published
Universally bounded operators on von Neumann algebras of type II*U1
Christensen, Erik, 1994, Algebraic Methods in Operator Theory. Boston: Birkhäuser Verlag, p. 195-204Research output: Chapter in Book/Report/Conference proceeding › Book chapter › Research
- 1989
- Published
A survey of completely bounded operators
Christensen, Erik & Sinclair, A. M., Sep 1989, In: Bulletin of the London Mathematical Society. 21, 5, p. 417-448 32 p.Research output: Contribution to journal › Journal article › Research › peer-review
- Published
Completely bounded isomorphisms of injective von neumann algebras
Christensen, Erik & Sinclair, A. M., Jun 1989, In: Proceedings of the Edinburgh Mathematical Society. 32, 2, p. 317-327 11 p.Research output: Contribution to journal › Journal article › Research › peer-review
- Published
On the vanishing of Hn(A, A*) for certain C*-algebras
Christensen, Erik & Sinclair, A. M., Mar 1989, In: Pacific Journal of Mathematics. 137, 1, p. 55-63 9 p.Research output: Contribution to journal › Journal article › Research › peer-review
- 1988
- Published
Close operator algebras
Christensen, Erik, 1988, In: NATO ASI Series C Mathematical and Physical Sciences - Advanced Study Institute. 247 , p. 537 - 556 20 p.Research output: Contribution to journal › Conference article › Research › peer-review
- 1987
- Published
Completely bounded multilinear maps and C*-algebraic cohomology
Christensen, Erik, Effros, E. G. & Sinclair, A., Jun 1987, In: Inventiones Mathematicae. 90, 2, p. 279-296 18 p.Research output: Contribution to journal › Journal article › Research › peer-review
- Published
Representations of completely bounded multilinear operators
Christensen, Erik & Sinclair, A. M., May 1987, In: Journal of Functional Analysis. 72, 1, p. 151-181 31 p.Research output: Contribution to journal › Journal article › Research › peer-review
- Published
The algebra of generalized compacts associated with a von Neumann algebra
Christensen, Erik, 1987, Operator Theory: Advances and applications.. Birkhäuser Verlag, Vol. 24. p. 51 - 58 8 p.Research output: Chapter in Book/Report/Conference proceeding › Article in proceedings › Research › peer-review
- 1986
- Published
Similarities of II_1 factors with property Gamma
Christensen, Erik, 1986, In: Journal of Operator Theory. 15, 2, p. 281 - 288 8 p.Research output: Contribution to journal › Journal article › Research › peer-review
- 1984
- Published
Properly infinite aw*-algebras are monotone sequentially complete
Christensen, Erik & Pedersen, G. K., Jul 1984, In: Bulletin of the London Mathematical Society. 16, 4, p. 407-410 4 p.Research output: Contribution to journal › Journal article › Research › peer-review
- Published
Pertrurbationer af operatoralgebraer
Christensen, Erik, 1984, 50 p.Research output: Book/Report › Book › Research › peer-review
- 1983
- Published
Completely order isomorphic and close C-algebras need not BE, *-isomorphic
Choi, M. D. & Christensen, Erik, Nov 1983, In: Bulletin of the London Mathematical Society. 15, 6, p. 604-610 7 p.Research output: Contribution to journal › Journal article › Research › peer-review
- 1982
- Published
Measures on projections and physical states
Christensen, Erik, Dec 1982, In: Communications in Mathematical Physics. 86, 4, p. 529-538 10 p.Research output: Contribution to journal › Journal article › Research › peer-review
- Published
Derivations and their relation to perturbations of operator algebras
Christensen, Erik, 1982, American Mathematical Society Symposia . Vol. 38. p. 261 - 273 13 p.Research output: Chapter in Book/Report/Conference proceeding › Article in proceedings › Research › peer-review
- Published
Extensions of derivations II
Christensen, Erik, 1982, In: Mathematica Scandinavica. 50, p. 111 -122 12 p.Research output: Contribution to journal › Journal article › Research › peer-review
- 1981
- Published
On non-selfadjoint representations of C*-algebras
Christensen, Erik, 1981, In: American Journal of Mathematics. 103, p. 817 - 833 17 p.Research output: Contribution to journal › Journal article › Research › peer-review
- 1980
- Published
Near inclusions of C*-algebras
Christensen, Erik, Jul 1980, In: Acta Mathematica. 144, 1, p. 249-265 17 p.Research output: Contribution to journal › Journal article › Research › peer-review
- Published
Commutants of nest algebras modulo the compact operators
Christensen, Erik & Peligrad, C., Feb 1980, In: Inventiones Mathematicae. 56, 1, p. 113-116 4 p.Research output: Contribution to journal › Journal article › Research › peer-review
- 1979
- Published
Subalgebras of a finite algebra
Christensen, Erik, Feb 1979, In: Mathematische Annalen. 243, 1, p. 17-29 13 p.Research output: Contribution to journal › Journal article › Research › peer-review
- Published
Cohomology of operator algebras and quantum dynamical semigroups.
Christensen, Erik & Evans , D. E., 1979, In: Journal of the London Mathematical Society. 20, 2, p. 358-368 11 p.Research output: Contribution to journal › Journal article › Research › peer-review
- 1978
- Published
Generators of semigroups of completely positive maps
Christensen, Erik, Jun 1978, In: Communications in Mathematical Physics. 62, 2, p. 167-171 5 p.Research output: Contribution to journal › Journal article › Research › peer-review
- Published
Extension of derivations
Christensen, Erik, Feb 1978, In: Journal of Functional Analysis. 27, 2, p. 234-247 14 p.Research output: Contribution to journal › Journal article › Research › peer-review
- 1977
- Published
Derivations of nest algebras
Christensen, Erik, Jun 1977, In: Mathematische Annalen. 229, 2, p. 155-161 7 p.Research output: Contribution to journal › Journal article › Research › peer-review
- Published
Perturbation of operator algebras
Christensen, Erik, Feb 1977, In: Inventiones Mathematicae. 43, 1, p. 1-13 13 p.Research output: Contribution to journal › Journal article › Research › peer-review
- Published
Perturbations of operator algebras II.
Christensen, Erik, 1977, In: Indiana University Mathematics Journal. 26, p. 891 - 904 14 p.Research output: Contribution to journal › Journal article › Research › peer-review
- 1975
- Published
Perturbations of type I von neumann algebras
Christensen, Erik, Jan 1975, In: Journal of the London Mathematical Society. s2-9, 3, p. 395-405 11 p.Research output: Contribution to journal › Journal article › Research › peer-review
- 1972
- Published
Non-commutative integration for monotone sequentially closed C∗ algebras
Christensen, Erik, 1972, In: Mathematica Scandinavica. 31, p. 171-190 20 p.Research output: Contribution to journal › Journal article › Research › peer-review
ID: 4394
Most downloads
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140
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The block Schur product is a Hadamard product
Research output: Contribution to journal › Journal article › Research › peer-review
Published -
79
downloads
On the complete boundedness of the Schur block product
Research output: Contribution to journal › Journal article › Research › peer-review
Published -
22
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Decompositions of block schur products
Research output: Contribution to journal › Journal article › Research › peer-review
Published