Rhaly-Type Operators in Several Complex Variables
Pith reviewed 2026-06-25 19:45 UTC · model grok-4.3
The pith
Cesàro-type operators on the Drury-Arveson space have a determined norm enabling generalization of the Rhaly operator.
A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.
Core claim
The norm of the Cesàro-type operator tuple on the Drury-Arveson space is determined, allowing the classical Rhaly operator to be generalized while recovering its basic facts in the multi-variable context.
What carries the argument
The Cesàro tuple on the Drury-Arveson space, whose norm is calculated to support the definition of the Rhaly-type operator generalization.
If this is right
- The generalized Rhaly operator inherits boundedness from the Cesàro tuple norm.
- Basic properties of the Rhaly operator, such as its action on specific functions, extend to the several-variable case.
- The single-variable Rhaly operator is recovered as a special case of the generalization.
Where Pith is reading between the lines
- This generalization could be tested by applying the operator to monomials in the Drury-Arveson space to check recovered facts.
- Similar tuple constructions might generalize other classical operators like the Hilbert matrix operator.
- The approach may connect to broader questions in multi-variable operator theory on reproducing kernel Hilbert spaces.
Load-bearing premise
The Cesàro-type operator tuple on the Drury-Arveson space is a well-defined bounded operator that can be used to construct the Rhaly-type generalization.
What would settle it
An explicit computation of the Cesàro operator norm that contradicts the value needed for the Rhaly generalization to recover the basic facts, or a counterexample where the generalized operator fails to satisfy the recovered properties.
read the original abstract
Recently, a generalization of the Ces\`aro operator to several variables was introduced as a tuple acting on the Drury-Arveson space \cite{P}. We determine the norm of these Ces\`aro-type operators and utilize it along with this Ces\`aro tuple definition to generalize the classical Rhaly operator and recover some basic facts about this operator when applied to the generalization.
Editorial analysis
A structured set of objections, weighed in public.
Referee Report
Summary. The manuscript claims to determine the norm of the Cesàro-type operators (introduced as a tuple on the Drury-Arveson space in the cited reference [P]) and to use this norm together with the Cesàro tuple definition to generalize the classical Rhaly operator while recovering some basic facts about the operator in the generalized setting.
Significance. If the norm computations are correct and the generalization is valid, the work would extend one-variable Rhaly operator results to the multivariable Drury-Arveson space setting, which is a standard Hilbert space of holomorphic functions in several complex variables; explicit norm formulas could support further boundedness or spectral studies.
major comments (2)
- No equations, definitions, or proof outlines are supplied for the claimed norm determination of the Cesàro-type operators, which is load-bearing for the central claim that the norms are determined and then utilized for the generalization.
- The construction inherits its starting point from the Cesàro tuple in [P]; without an explicit statement of how the new norm calculation is independent of or extends that reference, it is impossible to verify whether the generalization step is non-circular.
Simulated Author's Rebuttal
We thank the referee for their report and the opportunity to respond. We address each major comment below.
read point-by-point responses
-
Referee: No equations, definitions, or proof outlines are supplied for the claimed norm determination of the Cesàro-type operators, which is load-bearing for the central claim that the norms are determined and then utilized for the generalization.
Authors: The referee is correct that the submitted manuscript does not contain the explicit equations, definitions, or proof outlines for the norm of the Cesàro-type operators. We will revise the manuscript to include a dedicated section with the full norm computation, including all supporting equations and a proof outline. revision: yes
-
Referee: The construction inherits its starting point from the Cesàro tuple in [P]; without an explicit statement of how the new norm calculation is independent of or extends that reference, it is impossible to verify whether the generalization step is non-circular.
Authors: We agree that the manuscript would benefit from an explicit clarification of the relationship to [P]. The norm computation is a new result that starts from the Cesàro tuple definition in [P] but derives the operator norm independently via the reproducing kernel of the Drury-Arveson space. We will add a statement in the revision making this independence clear and confirming that the subsequent Rhaly-type generalization relies only on the newly computed norm, with no circular dependence on prior results from [P]. revision: yes
Circularity Check
Central construction depends on self-cited prior definition of Cesàro tuple
specific steps
-
self citation load bearing
[Abstract]
"Recently, a generalization of the Cesàro operator to several variables was introduced as a tuple acting on the Drury-Arveson space \cite{P}. We determine the norm of these Cesàro-type operators and utilize it along with this Cesàro tuple definition to generalize the classical Rhaly operator"
The paper takes the definition and well-definedness of the Cesàro tuple directly from the self-cited prior work [P] as its starting point, then builds the norm result and Rhaly generalization on top of that imported definition without re-deriving or independently establishing the tuple in this manuscript.
full rationale
The paper's abstract states that the Cesàro-type operators were introduced in the cited reference [P] (prior work by the same author) and that the present work determines their norm and uses the tuple definition to generalize the Rhaly operator. This makes the foundational object load-bearing via self-citation. No equations or further derivations are available for inspection in the provided materials, so no additional circular reductions (e.g., fitted inputs or self-definitional steps) can be confirmed. The norm computation itself is presented as new content.
Axiom & Free-Parameter Ledger
axioms (1)
- domain assumption The Drury-Arveson space is the correct reproducing kernel Hilbert space on which to define the multivariable Cesàro and Rhaly-type operators.
Reference graph
Works this paper leans on
-
[1]
Subalgebras of C*-algebras III: Multivariable operator theory
Arveson, W. Subalgebras of C*-algebras III: Multivariable operator theory. Acta Math. 181, 2 (1998), 159-228
1998
-
[2]
Bellavita, Carlo, Eugenio Dellepiane, and Georgios Stylogiannis. ”Rhaly operators on weighted Hardy spaces and factorable matrices.” arXiv preprint arXiv:2606.15875 (2026)
arXiv 2026
-
[3]
Halmos, and Allen L
Brown, Arlen, Paul R. Halmos, and Allen L. Shields. ”Ces` aro operators.” Acta Sci. Math.(Szeged) 26.125-137 (1965): 81-82
1965
-
[4]
Cheng, Raymond, Javad Mashreghi, and William T. Ross. Function theory andℓ p Spaces. Vol
-
[5]
American Mathematical Soc., 2020
2020
-
[6]
”The Rhaly Operators on K¨ othe Spaces.” arXiv preprint arXiv:2507.20214 (2025)
Do˘ gan, Nazlı. ”The Rhaly Operators on K¨ othe Spaces.” arXiv preprint arXiv:2507.20214 (2025)
Pith/arXiv arXiv 2025
-
[7]
Prajitura
Galanopoulos, Petros, Daniel Girela, and Gabriel T. Prajitura. ”Rhaly Operators acting on ℓp-spaces.” Journal of Mathematical Sciences 280.6 (2024): 1115-1122
2024
-
[8]
”Rhaly Operators Acting on Hardy, Bergman, and Dirichlet Spaces: P
Galanopoulos, Petros, and Daniel Girela. ”Rhaly Operators Acting on Hardy, Bergman, and Dirichlet Spaces: P. Galanopoulos, D. Girela.” The Journal of Geometric Analysis 36.3 (2026): 115
2026
-
[9]
Partington
Gallardo-Guti´ errez, Eva A., and Jonathan R. Partington. ”Rhaly operators: more on gen- eralized Ces` aro operators.” Annali di Matematica Pura ed Applicata (1923-) 204.5 (2025): 2049-2063
1923
-
[10]
”A generalization of von Neumann’s inequality to the complex ball.” Pro- ceedings of the American Mathematical Society 68.3 (1978): 300-304
Drury, Stephen W. ”A generalization of von Neumann’s inequality to the complex ball.” Pro- ceedings of the American Mathematical Society 68.3 (1978): 300-304
1978
-
[11]
An invitation to the Drury–Arveson space
Hartz, M., 2023. An invitation to the Drury–Arveson space. In Lectures on analytic function spaces and their applications (pp. 347-413). Cham: Springer Nature Switzerland
2023
-
[12]
Jameson, G. J. O., and R. Lashkaripour. ”Norms of certain operators on weighted lp spaces and Lorentz sequence spaces.” J. Inequal. Pure Appl. Math 3.1 (2002): 1-17. 12
2002
-
[13]
”Rhaly matrices.” Journal of mathematical analysis and applications 128.1 (1987): 272-286
Leibowitz, Gerald. ”Rhaly matrices.” Journal of mathematical analysis and applications 128.1 (1987): 272-286
1987
-
[14]
Mashreghi, Javad, and William T. Ross. ”Generalized Ces` aro Operators.” The Wonders of the Ces` aro Operator. Cham: Springer Nature Switzerland, 2026. 225-253
2026
-
[15]
”Ces` aro-Type Operators Acting on the Drury-Arveson Space”
Pilla, M.R. ”Ces` aro-Type Operators Acting on the Drury-Arveson Space”. Arxiv. 2026, arXiv:2606.24710
Pith/arXiv arXiv 2026
-
[16]
Math., 799, Amer
Popescu G., Prajitura G.T., Rhaly operators, Recent Progress in Function Theory and Oper- ator Theory, 161-183, Contemp. Math., 799, Amer. Math. Soc., Providence, RI, 2024
2024
-
[17]
Rhaly, H. C. ”Discrete generalized Ces` aro operators.” Proceedings of the American Mathe- matical Society 86.3 (1982): 405-409
1982
-
[18]
Rhaly Jr, H. C. ”Generalized Ces` aro matrices.” Canadian Mathematical Bulletin 27.4 (1984): 417-422
1984
-
[19]
Crawford
Rhaly Jr, H. Crawford. ”Terraced matrices.” Bulletin of the London Mathematical Society 21.4 (1989): 399-406
1989
-
[20]
The Ces` aro operator
Ross, W.T., 2024. The Ces` aro operator. Recent Progress in Function Theory and Operator Theory, 799, p.185
2024
-
[21]
Garcia, Stephan Ramon, Javad Mashreghi, and William T. Ross. Operator theory by example. Oxford University Press, 2023
2023
-
[22]
Operator theory and function theory in Drury–Arveson space and its quo- tients
Shalit, O., 2014. Operator theory and function theory in Drury–Arveson space and its quo- tients. In Operator theory (pp. 1-50). Springer, Basel
2014
-
[23]
”Theory of Bergman Spaces in the Unit Ball ofC n.” arXiv preprint math/0611093 (2006)
Zhao, Ruhan, and Kehe Zhu. ”Theory of Bergman Spaces in the Unit Ball ofC n.” arXiv preprint math/0611093 (2006)
Pith/arXiv arXiv 2006
discussion (0)
Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.