Unbounded Order-to-Order Continuous Operators on Riesz Spaces

Document Type : Research Article

Authors

Department of Mathematics and Application Faculty of Sciences University of Mohaghegh Ardabili, Ardabil, Iran

Abstract

‎Let $E$ and $F$ be two Riesz spaces‎. ‎An operator $T \colon E\rightarrow F$ between two Riesz spaces is said to be‎ ‎unbounded order-to-order continuous whenever $x _\alpha \xrightarrow{uo}0$ in $E$ implies $Tx _\alpha \xrightarrow{o}0$ in $F$ for each net $(x_\alpha)\subseteq E$‎. ‎This paper aims to investigate several properties of a novel class of operators and their connections to established operator classifications‎. ‎Furthermore‎, ‎we introduce a new class of operators‎, ‎which we refer to as order-to-unbounded order continuous operators‎. ‎An operator $T \colon E\rightarrow F$ between two Riesz spaces is said to be‎ ‎order-to-unbounded order continuous (for short‎, ‎$ouo$-continuous)‎, ‎if $x _\alpha \xrightarrow{o}0$ in $E$ implies $Tx _\alpha \xrightarrow{uo}0$ in $F$ for each net $(x_\alpha)\subseteq E$‎. ‎In this manuscript‎, ‎we investigate the lattice properties of a certain class of objects and demonstrate that‎, ‎under certain conditions‎, ‎order continuity is equivalent to unbounded order-to-order continuity of operators on Riesz spaces‎. ‎Additionally‎, ‎we establish that the set of all unbounded order-to-order continuous linear functionals on a Riesz space $E$ forms a band of $E^\sim$.

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1. Y. A. Abramovich, C. D. Aliprantis, An Invitation to Operator Theory, American Mathematical Society, Providence, (2002).
2. C. D. Aliprantis, O. Burkinshaw, Positive operators, Springer Science & Business Media, (2006).
3. A. Bahramnezhad, K. Haghnejad Azar, Unbounded order continuous operators on Riesz spaces, Positivity, 22, 837–843 (2018).
4. Y. Deng, M. O’Brien, V. G. Troitsky, Unbounded norm convergence in Banach lattices, Positivity, 21, 963–974 (2017).
5. R. Demarr, Partially ordered linear spaces and locally convex linear topological spaces, Illinois J. Math., 8, 601–606  (1964).
6. N. Gao, Unbounded order convergence in dual spaces, J. Math. Anal. Appl., 419(1), 347–354 (2014).
7. N. Gao, V. G. Troitsky, F. Xanthos, Uo-convergence and its aplications to cesaro means in Banach lattices, Israel J. Math., 220, 649–689 (2017).
8. K. Haghnejad Azar, M. Matin, R. Alavizadeh, Unbounded order-norm continuous and unbounded norm continuous operators, Filomat, 35(13), 4417–4426 (2021).
9. A. Jalili, K. Haghnejad, M. Moghimi, Order-to-topology continuous operators, Positivity, 25(2), 1–10, (2021). 
10. M. Kandic, M. A. A. Marabeh, V. G. Troitsky, Unbounded norm topology in Banach lattices, J. Math. Anal. Appl., 451, 259–279 (2017).
11. H. Nakano, Ergodic theorems in semi-ordered linear spaces, Ann. Math., 49(3), 538–556 (1948).
12. B. Turan, B. Altin, H. Gürkök, On unbounded order continuous operators. Turkish Journal of Mathematics, 46, 3391–3399 (2022).
13. A. W. Wickstead, Weak and unbounded order convergence in Banach lattices, J. Austral. Math. Soc. Ser. A, 24, 312–319 (1977). 
Volume 8, Issue 1
July 2023
Pages 82-90
  • Receive Date: 04 August 2023
  • Revise Date: 06 January 2024
  • Accept Date: 21 January 2024
  • Publish Date: 26 January 2024