Abstract
We study the relative position of three subspaces in an infinitedimensional Hilbert space. In the finite-dimensional case over an arbitrary field, Brenner described the general position of three subspaces completely. We extend it to a certain class of three subspaces in an infinite-dimensional Hilbert space over the complex numbers.
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Communicated by L. Molnár
The authors are supported by JSPS KAKENHI Grant number 23654053 and 25287019.
Acknowledgment.
We would like to thank an anonymous former referee for his critical reading of the original version. His many valuable comments and suggestions have improved our paper greatly.
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Enomoto, M., Watatani, Y. Relative position of three subspaces in a Hilbert space. ActaSci.Math. 85, 519–537 (2019). https://doi.org/10.14232/actasm-018-821-x
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DOI: https://doi.org/10.14232/actasm-018-821-x