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arXiv · 2504.12827

Direct Sum of Lower Semi-Frames in Hilbert Spaces

Hemalatha M·P. Sam Johnson·Harikrishnan P. K
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Abstract

In this paper, structural properties of lower semi-frames in separable Hilbert spaces are explored with a focus on transformations under linear operators (may be unbounded). Also, the direct sum of lower semi-frames, providing necessary and sufficient conditions for the preservation of lower semi-frame structure, is examined.

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Hemalatha M, P. Sam Johnson, Harikrishnan P. K. 2025-04-17. Direct Sum of Lower Semi-Frames in Hilbert Spaces. https://arxiv.org/abs/2504.12827

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