We construct the Henstock-Kurzweil (HK) integral as an extension of a linear form initially defined on $ L^{1} $, but which is not continuous in this space. This gives us an alternative way to prove existing results. In particular, we give a new characterization of the dual space of Henstock-Kurzweil integrable functions in terms of a quotient space.
Citation: Juan H. Arredondo, Genaro Montaño, Francisco J. Mendoza. A new characterization of the dual space of the HK-integrable functions[J]. AIMS Mathematics, 2024, 9(4): 8250-8261. doi: 10.3934/math.2024401
We construct the Henstock-Kurzweil (HK) integral as an extension of a linear form initially defined on $ L^{1} $, but which is not continuous in this space. This gives us an alternative way to prove existing results. In particular, we give a new characterization of the dual space of Henstock-Kurzweil integrable functions in terms of a quotient space.
[1] | G. Liu, The dual of the Henstock-Kurzweil space, Real Anal. Exch., 22 (1996-97), 105–121. https://doi.org/10.2307/44152737 doi: 10.2307/44152737 |
[2] | P. Y. Lee, Lanzhou lectures on Henstock integration, World Scientific, Singapore, 1989. https://doi.org/10.1142/0845 |
[3] | A. Alexiewicz, Linear functionals on Denjoy integrable functions, Coll. Math., 1 (1948), 289–293. |
[4] | I. Gasparis, An extension of James's compactness theorem, J. Funct. Anal., 268 (2015), 194–209. https://doi.org/10.1016/j.jfa.2014.10.021 doi: 10.1016/j.jfa.2014.10.021 |
[5] | R. C. James, Characterizations of reflexivity, Stud. Math., 23 (1964), 205–216. Available from: http://eudml.org/doc/217072. |
[6] | T. H. Hildebrandt, Introduction to the theory of integration, Publisher Academic Press, New York, 1963. https://doi.org/10.1017/S0013091500025955 |
[7] | C. Swartz, Introduction to gauge integrals, World Scientific, Singapore, 2001. https://doi.org/10.1142/4361 |
[8] | G. Liu, On necessary conditions for Henstock integrability, Real Anal. Exch., 8 (1992/93), 522–531. |
[9] | P. Y. Lee, V. Rudolf, The integral an easy approach after Kurzweil and Henstock, Cambridge University Press, Cambridge, 2000. |
[10] | G. A. Monteiro, A. Slavík, M. Tvrdý, Kurzweil-Stieltjes integral: Theory and applications, World Scientific, Singapore, 2017. https://doi.org/10.1142/9432 |
[11] | J. J. Benedetto, W. Czaja, Integration and modern analysis, Birkhäuser, Boston, 2009. https://doi.org/10.1007/978-0-8176-4656-1 |
[12] | R. Kannan, C. K. Krueger, Advanced analysis on the real line, Springer, New York, 1996. https://doi.org/10.1007/978-1-4613-8474-8 |
[13] | D. S. Kurtz, C. W. Swartz, Theories of integration: The integrals of Riemann, Lebesgue, Henstock-Kurzweil, and McShane, 2 Eds., World Scientific, Singapore, 2012. https://doi.org/10.1142/5538 |
[14] | T. Apostol, Mathematical analysis, 2 Eds., Pearson Education, Boston, 1974. |
[15] | R. G. Bartle, A modern theory of integration, Graduate Studies in Mathematics, American Mathematical Society, Providence, 32 (2001). |
[16] | M. Reed, B. Simon, Methods of modern analysis, volume I: Functional analysis, Academic Press, London, 1980. |
[17] | J. B. Conway, A course in functional analysis, 2 Eds., Springer, New York, 1990. https://doi.org/10.1007/978-1-4757-4383-8 |
[18] | N. Dunford, J. T. Schwartz, Linear operators, part I: General theory, Interscience Publishers, New York, 1957. |
[19] | W. Rudin, Real and complex analysis, 3 Eds., McGraw-Hill, Singapore, 1987. |
[20] | M. Carter, B. van Brunt, The Lebesgue-Stieltjes integral: A practical introduction, Springer, New York, 2000. https://doi.org/10.1007/978-1-4612-1174-7 |
[21] | R. C. James, Reflexivity and the sup of linear functionals, Isr. J. Math., 13 (1972), 289–300. https://doi.org/10.1007/BF02762803 doi: 10.1007/BF02762803 |
[22] | M. Jiménez, J. P. Moreno, A note on norm attaining functionals, P. Am. Math. Soc., 126 (1998), 1989–1997. |