Half-orthogonal sets of idempotents
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- by Victor P. Camillo and Pace P. Nielsen PDF
- Trans. Amer. Math. Soc. 368 (2016), 965-987 Request permission
Abstract:
We improve several results in the literature focused on lifting idempotents, by either removing the lifting hypothesis or weakening other assumptions. We prove that countable sets of idempotents, which are orthogonal modulo an enabling ideal, lift to orthogonal idempotents. Left associates of liftable idempotents also lift modulo the Jacobson radical. Additionally, we exhibit situations when half-orthogonal sets of idempotents can be orthogonalized by multiplying by a unit. We finish by proving a number of results on directs sums of modules with the exchange property.References
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Additional Information
- Victor P. Camillo
- Affiliation: Department of Mathematics, University of Iowa, Iowa City, Iowa 52242
- Email: camillo@math.uiowa.edu
- Pace P. Nielsen
- Affiliation: Department of Mathematics, Brigham Young University, Provo, Utah 84602
- MR Author ID: 709329
- Email: pace@math.byu.edu
- Received by editor(s): August 28, 2013
- Received by editor(s) in revised form: December 11, 2013
- Published electronically: May 6, 2015
- © Copyright 2015 American Mathematical Society
- Journal: Trans. Amer. Math. Soc. 368 (2016), 965-987
- MSC (2010): Primary 16U99; Secondary 16D70, 16N20
- DOI: https://doi.org/10.1090/tran/6350
- MathSciNet review: 3430355