Porosity in the context of hypergroups
Eurasian mathematical journal, Tome 15 (2024) no. 1, pp. 75-90.

Voir la notice de l'article provenant de la source Math-Net.Ru

In this paper we show that the set of all elements $g\in L^p(\mathcal{H})$ for which $(|g|*|g|)(x)\infty$ for a center element $x\in B$, is $\sigma$-$c$-lower porous, where $p > 2$, $\mathcal{H}$ is a non-compact unimodular hypergroup and $B$ is some special symmetric compact neighborhood of the identity element. As an application, we give some new equivalent condition for the finiteness of a discrete Hermitian hypergroup. Moreover, we give some sufficient conditions for the set of all pairs $(f, g)$ in $L^p(\mathcal{H})\times L^q(\mathcal{H})$ for which for a center element $x\in B$, $(|f|*|g|)(x)\infty$, is a $\sigma$-$c$-lower porous, where $p, q > 1$ with $\frac1p+\frac1q1$. Also, we show that the complement of this set is spaceable in $L^p(\mathcal{H})\times L^q(\mathcal{H})$.
@article{EMJ_2024_15_1_a6,
     author = {S. M. Tabatabaie and A. R. Bagheri Salec and H. R. J. Allami},
     title = {Porosity in the context of hypergroups},
     journal = {Eurasian mathematical journal},
     pages = {75--90},
     publisher = {mathdoc},
     volume = {15},
     number = {1},
     year = {2024},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/EMJ_2024_15_1_a6/}
}
TY  - JOUR
AU  - S. M. Tabatabaie
AU  - A. R. Bagheri Salec
AU  - H. R. J. Allami
TI  - Porosity in the context of hypergroups
JO  - Eurasian mathematical journal
PY  - 2024
SP  - 75
EP  - 90
VL  - 15
IS  - 1
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/EMJ_2024_15_1_a6/
LA  - en
ID  - EMJ_2024_15_1_a6
ER  - 
%0 Journal Article
%A S. M. Tabatabaie
%A A. R. Bagheri Salec
%A H. R. J. Allami
%T Porosity in the context of hypergroups
%J Eurasian mathematical journal
%D 2024
%P 75-90
%V 15
%N 1
%I mathdoc
%U http://geodesic.mathdoc.fr/item/EMJ_2024_15_1_a6/
%G en
%F EMJ_2024_15_1_a6
S. M. Tabatabaie; A. R. Bagheri Salec; H. R. J. Allami. Porosity in the context of hypergroups. Eurasian mathematical journal, Tome 15 (2024) no. 1, pp. 75-90. http://geodesic.mathdoc.fr/item/EMJ_2024_15_1_a6/

[1] I. Akbarbaglu, S. Maghsoudi, “On certain porous sets in the Orlicz space of a locally compact group”, Colloquium Math, 129:1 (2012), 99–111 | DOI | MR | Zbl

[2] I. Akbarbaglu, S. Maghsoudi, J. B. Seoane-Sepúlveda, “Porosity and the $l^p$-conjecture for semigroups”, RACSAM, 110 (2016), 7–16 | DOI | MR | Zbl

[3] A. R. Bagheri Salec, S. Ivković, S. M. Tabatabaie, “Spaceability on some classes of Banach spaces”, Math. Ineq. Appl, 25:3 (2022), 659–672 | MR | Zbl

[4] F. Bayart, “Porosity and hypercyclic operators”, Proceedings of the American Mathematical Society, 133:11 (2005), 3309–3316 | DOI | MR | Zbl

[5] W. R. Bloom, H. Heyer, Harmonic Analysis of Probability Measures on Hypergroups, De Gruyter, Berlin, 1995 | MR | Zbl

[6] C. F. Dunkl, “The measure algebra of a locally compact hypergroup”, Trans. Amer. Math. Soc., 179 (1973), 331–348 | DOI | MR | Zbl

[7] C. F. Dunkl, D. E. Ramirez, “A family of countably compact $P_*$-hypergroups”, Trans. Amer. Math. Soc, 202 (1975), 339–356 | MR | Zbl

[8] S. Gla̧b, F. Strobin, “Porosity and the $L^p$-conjecture”, Arch. Math. (Basel), 95 (2010), 583–592 | DOI | MR | Zbl

[9] S. Gla̧b, F. Strobin, “Dichotomies for $L^p$ spaces”, J. Math. Anal. Appl, 368 (2010), 382–390 | DOI | MR | Zbl

[10] S. Gla̧b, F. Strobin, “Spaceability of sets in $L_p\times L_q$ and $C_0\times C_0$”, J. Math. Anal. Appl, 440:2 (2016), 451–465 | DOI | MR | Zbl

[11] R. I. Jewett, “Spaces with an abstract convolution of measures”, Adv. Math, 18 (1975), 1–101 | DOI | MR | Zbl

[12] V. Kumar, K. A. Ross, A. I. Singh, “Hypergroup deformations of semigroups”, Semigroup Forum, 99:1 (2019), 169–195 | DOI | MR | Zbl

[13] V. Kumar, K. A. Ross, A. I. Singh, “An addendum to “Hypergroup deformations of semigroups””, Semigroup Forum, 99:1 (2019), 196–197 | DOI | MR

[14] V. Kumar, K. A. Ross, A. I. Singh, “Ramsey theory for hypergroups”, Semigroup Forum, 100:2 (2020), 482–504 | DOI | MR | Zbl

[15] V. Kumar, R. Sarma, N. S. Kumar, “Orlicz spaces on hypergroups”, Publ. Math. Debrecen, 94 (2019), 31–47 | DOI | MR | Zbl

[16] V. Kumar, R. Sarma, “The Hausdorff-Young inequality for Orlicz spaces on compact hypergroups”, Colloquium Mathematicum, 160 (2020), 41–51 | DOI | MR | Zbl

[17] V. Kumar, “Orlicz spaces and amenability of hypergroups”, Bull. Iran. Math. Soc, 49 (2020), 1035–1043 | DOI | MR

[18] K. A. Ross, “Centers of hypergroups”, Trans. Amer. Math. Soc., 243 (1978), 251–269 | DOI | MR | Zbl

[19] R. Spector, “Apercu de la theorie des hypergroups”, Analyse Harmonique sur les Groups de Lie, Lec. Notes Math. Ser., 497, Springer, 1975, 643–673 | DOI | MR

[20] R. Spector, “Measures invariantes sur les hypergroups”, Trans. Amer. Math. Soc., 239 (1978), 147–165 | DOI | MR | Zbl

[21] S. M. Tabatabaie, F. Haghighifar, “$L^p$-Conjecture on locally compact hypergroups”, Sahand Communications Math. Anal, 12:1 (2018), 121–130 | Zbl

[22] A. Villani, “Another note on the inclusion $L^p(\lambda)\subset L^q(\lambda)$”, Amer. Math. Monthly, 92 (1985), 485–487 | MR | Zbl

[23] L. Zájiček, “Porosity and $\sigma$-porous”, Real Anal. Exchange, 13 (1987/1988), 314–350 | DOI | MR

[24] L. Zájiček, “On-porous sets in abstract spaces”, Abstr. Appl. Anal, 5 (2005), 509–534 | MR | Zbl

[25] M. Zelený, “The Banach-Mazur game and-porosity”, Fund. Math, 150:3 (1996), 197–210 | DOI | MR | Zbl