Abstract
The present paper concerns the homogeneity and similarity of operators in Cowen-Douglas class \(B_n(\Omega )\). Let E be the Hermitian holomorphic vector bundle induced by \(T\in B_n(\mathbb {D})\), and \(E_{\alpha }\) be the Hermitian holomorphic vector bundle induced by \(\phi _{\alpha }(T)\), where \(\phi _{\alpha }\) is a M\(\ddot{o}\)bius transformation of the unit disk \(\mathbb {D}\). Assume that the holomorphic Hermitian vector bundle \(E_{\alpha }\) is congruent to \(E\otimes \mathcal {L}_{\alpha }\) for some line bundle \(\mathcal {L}_{\alpha }\) over \(\mathbb {D}\), for each \(\alpha \in \mathbb {D}\). Then it is shown that \(\mathcal {L}_{\alpha }\) must be the trivial bundle and T is homogeneous. Furthermore, we investigate the similarity of operators with Fredholm index n associate with Hermitian holomorphic bundles. This characterization is given in terms of the factorization of generalized holomorphic curve induced by the corresponding holomorphic bundles.
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The first author was supported by National Natural Science Foundation of China (Grant no. 12001159). The second author was supported by National Natural Science Foundation of China (Grant nos. 11922108 and 11831006).
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Communicated by Raul Curto.
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Hou, Y., Ji, K. & Zhao, L. Factorization of generalized holomorphic curve and homogeneity of operators. Banach J. Math. Anal. 15, 43 (2021). https://doi.org/10.1007/s43037-021-00127-9
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DOI: https://doi.org/10.1007/s43037-021-00127-9