H^infty Functional Calculus for a Commuting Pair of Ritt_(E) Operators
Pith reviewed 2026-05-22 17:06 UTC · model grok-4.3
The pith
Commuting pairs of Ritt_E operators on Banach spaces admit a joint bounded holomorphic functional calculus precisely when equivalent criteria on L^p spaces hold.
A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.
Core claim
The paper establishes that for commuting pairs of Ritt_E operators, the existence of a joint bounded H^∞ functional calculus is equivalent to a set of conditions that can be verified by reducing to the case of sectorial operators via a transfer principle and using a joint dilation theorem on appropriate Banach spaces, with explicit criteria provided for L^p spaces.
What carries the argument
The transfer principle relating the bounded holomorphic functional calculus for Ritt_E pairs to their sectorial counterparts, combined with the joint dilation theorem for commuting tuples.
If this is right
- The joint calculus problem for Ritt_E pairs reduces directly to the corresponding sectorial operator problem.
- The dilation theorem extends the result to many Banach spaces beyond Hilbert spaces, including L^p spaces.
- Verification of the joint bounded calculus reduces to checking a finite list of equivalent conditions formulated on L^p spaces.
- When the criteria hold, the pair generates a bounded joint holomorphic functional calculus on the appropriate function algebra.
Where Pith is reading between the lines
- The same transfer and dilation approach may apply to commuting tuples larger than pairs.
- The criteria could be used to study stability and spectrum properties of the generated semigroup in evolution equations.
- Analogous reduction techniques might work for other operator classes that admit sectorial-like dilations on Banach spaces.
Load-bearing premise
The transfer principle and joint dilation theorem hold for commuting pairs of Ritt_E operators on a broad class of Banach spaces, allowing reduction to the sectorial case.
What would settle it
A concrete commuting pair of Ritt_E operators on an L^p space for which the listed equivalent criteria fail yet a joint bounded H^∞ calculus still exists, or vice versa.
Figures
read the original abstract
In this article, we develop a framework for the joint functional calculus of commuting pair of $\text{Ritt}_{\text{E}}$ operators on Banach spaces. We establish a transfer principle that relates the bounded holomorphic functional calculus for pair of $\text{Ritt}_{\text{E}}$ operators to that of their associated sectorial counterparts. In addition, we prove a joint dilation theorem for commuting tuples of $\text{Ritt}_{\text{E}}$ operators on a broad class of Banach spaces. As a key application, we obtain an equivalent set of criteria on $L^p$-spaces for $1<p< \infty$ that determine when a commuting pair of $\text{Ritt}_{\text{E}}$ operators admits a joint bounded functional calculus.
Editorial analysis
A structured set of objections, weighed in public.
Referee Report
Summary. The manuscript develops a framework for the joint H^∞ functional calculus of commuting pairs of Ritt_E operators on Banach spaces. It establishes a transfer principle relating the bounded holomorphic functional calculus for such pairs to their sectorial counterparts and proves a joint dilation theorem for commuting tuples of Ritt_E operators on a broad class of Banach spaces. As a key application, it derives an equivalent set of criteria on L^p-spaces (1 < p < ∞) determining when a commuting pair admits a joint bounded functional calculus.
Significance. If the central results hold, the work is a solid contribution to operator theory on Banach spaces. It extends single-operator results on Ritt_E and sectorial operators to the commuting-pair setting via a transfer principle and joint dilation, providing a reduction that yields concrete equivalent criteria on L^p spaces. This is useful for applications and builds directly on established tools without introducing free parameters or ad-hoc constructions.
minor comments (2)
- The abstract and introduction would benefit from a brief explicit statement of the precise class of Banach spaces on which the joint dilation theorem holds, to make the scope immediately clear to readers.
- Notation for the joint functional calculus (e.g., the precise definition of the joint H^∞ calculus for pairs) should be introduced with a numbered equation in the preliminaries section for easier cross-reference.
Simulated Author's Rebuttal
We thank the referee for the positive assessment of our manuscript on the joint H^∞ functional calculus for commuting pairs of Ritt_E operators. We appreciate the recommendation for minor revision and will prepare a revised version accordingly. No specific major comments were raised in the report.
Circularity Check
No significant circularity detected in derivation chain
full rationale
The manuscript establishes a transfer principle relating the joint bounded holomorphic functional calculus for commuting Ritt_E operator pairs to their sectorial counterparts, together with a joint dilation theorem on a broad class of Banach spaces. These constructions are then applied to obtain equivalent criteria on L^p spaces (1 < p < ∞) by reducing the Ritt_E case to the sectorial setting and invoking known single-operator results in the commuting case. No step reduces by definition or construction to its own inputs, no parameters are fitted and relabeled as predictions, and no load-bearing premise rests on self-citation chains; the argument is self-contained against external operator-theoretic benchmarks.
Axiom & Free-Parameter Ledger
Reference graph
Works this paper leans on
-
[1]
M. A. Akcoglu and L. Sucheston,Dilations of positive contractions onL p spaces, Canad. Math. Bull.20(1977), no. 3, 285–292
work page 1977
-
[2]
thesis, Monash University, 1994
David William Albrecht,Functional calculi of commuting unbounded operators, Ph.D. thesis, Monash University, 1994
work page 1994
-
[3]
Andˆ o,On a pair of commutative contractions, Acta Sci
T. Andˆ o,On a pair of commutative contractions, Acta Sci. Math. (Szeged)24(1963), 88–90
work page 1963
-
[4]
C´ edric Arhancet, Stephan Fackler, and Christian Le Merdy,Isometric dilations andH ∞ calculus for bounded analytic semigroups and Ritt operators, Trans. Amer. Math. Soc.369 (2017), no. 10, 6899–6933
work page 2017
-
[5]
C´ edric Arhancet and Christian Le Merdy,Dilation of Ritt operators onL p-spaces, Israel J. Math.201(2014), no. 1, 373–414
work page 2014
-
[6]
Olivier Arrigoni and Christian Le Merdy,H ∞-functional calculus for commuting families of Ritt operators and sectorial operators, Oper. Matrices13(2019), no. 4, 1055–1090
work page 2019
-
[7]
S¨ onke Blunck,Analyticity and discrete maximal regularity onL p-spaces, J. Funct. Anal.183 (2001), no. 1, 211–230
work page 2001
-
[8]
Oualid Bouabdillah,Square functions associated withRitt E operators, Indag. Math. (N.S.) 36(2025), no. 5, 1417–1452. MR 4949890
work page 2025
-
[9]
Oualid Bouabdillah and Christian Le Merdy,Polygonal functional calculus for operators with finite peripheral spectrum, Israel J. Math.263(2024), no. 2, 517–551
work page 2024
-
[10]
Ronald R. Coifman and Guido Weiss,Transference methods in analysis, Conference Board of the Mathematical Sciences Regional Conference Series in Mathematics, vol. No. 31, American Mathematical Society, Providence, RI, 1976
work page 1976
-
[11]
Michael Cowling, Ian Doust, Alan McIntosh, and Atsushi Yagi,Banach space operators with a boundedH ∞ functional calculus, J. Austral. Math. Soc. Ser. A60(1996), no. 1, 51–89
work page 1996
-
[12]
Rajeev Gupta and Samya K. Ray,On a question of N. Th. Varopoulos and the constant C2(n), Ann. Inst. Fourier (Grenoble)68(2018), no. 6, 2613–2634
work page 2018
-
[13]
169, Birkh¨ auser Verlag, Basel, 2006
Markus Haase,The functional calculus for sectorial operators, Operator Theory: Advances and Applications, vol. 169, Birkh¨ auser Verlag, Basel, 2006
work page 2006
-
[14]
Michael Hartz,On von neumann’s inequality on the polydisc, Mathematische Annalen391 (2025), no. 4, 5235–5264
work page 2025
-
[15]
Guixiang Hong, Samya Kumar Ray, and Simeng Wang,Maximal ergodic inequalities for some positive operators on noncommutativeL p-spaces, J. Lond. Math. Soc. (2)108(2023), no. 1, 362–408
work page 2023
-
[16]
6, Walter de Gruyter & Co., Berlin, 1985, With a supplement by Antoine Brunel
Ulrich Krengel,Ergodic theorems, De Gruyter Studies in Mathematics, vol. 6, Walter de Gruyter & Co., Berlin, 1985, With a supplement by Antoine Brunel
work page 1985
-
[17]
Florence Lancien, Gilles Lancien, and Christian Le Merdy,A joint functional calculus for sectorial operators with commuting resolvents, Proc. London Math. Soc. (3)77(1998), no. 2, 387–414
work page 1998
-
[18]
Christian Le Merdy,H ∞-functional calculus and applications to maximal regularity, Semi- groupes d’op´ erateurs et calcul fonctionnel (Besan¸ con, 1998), Publ. Math. UFR Sci. Tech. Besan¸ con, vol. 16, Univ. Franche-Comt´ e, Besan¸ con, 1999, pp. 41–77
work page 1998
-
[19]
,H ∞ functional calculus and square function estimates for Ritt operators, Rev. Mat. Iberoam.30(2014), no. 4, 1149–1190
work page 2014
-
[20]
Christian Le Merdy and M. N. reshmi,Commuting families of polygonal type operators on Hilbert space, Adv. Oper. Theory10(2025), no. 2, Paper No. 33
work page 2025
-
[21]
Christian Le Merdy and Quanhua Xu,Maximal theorems and square functions for analytic operators onL p-spaces, J. Lond. Math. Soc. (2)86(2012), no. 2, 343–365
work page 2012
-
[22]
,Strongq-variation inequalities for analytic semigroups, Ann. Inst. Fourier (Grenoble) 62(2012), no. 6, 2069–2097
work page 2012
-
[23]
Alan McIntosh,Operators which have anH ∞ functional calculus, Miniconference on opera- tor theory and partial differential equations (North Ryde, 1986), Proc. Centre Math. Anal. Austral. Nat. Univ., vol. 14, Austral. Nat. Univ., Canberra, 1986, pp. 210–231
work page 1986
-
[24]
Parasar Mohanty and Samya Kumar Ray,On joint functional calculus for Ritt operators, Integral Equations Operator Theory91(2019), no. 2, Paper No. 14, 18
work page 2019
-
[25]
78, Cambridge University Press, Cambridge, 2002
Vern Paulsen,Completely bounded maps and operator algebras, Cambridge Studies in Ad- vanced Mathematics, vol. 78, Cambridge University Press, Cambridge, 2002. 26 SUMAN MONDAL, SUBHAJIT PALAI, AND SAMYA KUMAR RAY
work page 2002
-
[26]
V. V. Peller,Analogue of J. von Neumann’s inequality, isometric dilation of contractions and approximation by isometries in spaces of measurable functions, Trudy Mat. Inst. Steklov.155 (1981), 103–150, 185, Spectral theory of functions and operators, II
work page 1981
-
[27]
Gilles Pisier,Similarity problems and completely bounded maps, expanded ed., Lecture Notes in Mathematics, vol. 1618, Springer-Verlag, Berlin, 2001, Includes the solution to “The Halmos problem”
work page 2001
-
[28]
Samya Kumar Ray,On multivariate Matsaev’s conjecture, Complex Anal. Oper. Theory14 (2020), no. 4, Paper No. 42, 25
work page 2020
-
[29]
B´ ela Sz.-Nagy and Ciprian Foia¸s,Harmonic analysis of operators on Hilbert space, North- Holland Publishing Co., Amsterdam-London; American Elsevier Publishing Co., Inc., New York; Akad´ emiai Kiad´ o, Budapest, 1970, Translated from the French and revised
work page 1970
-
[30]
Jan van Neerven,Stochastic evolution equations, ISEM Lecture Notes, 2007
work page 2007
-
[31]
N. Th. Varopoulos,On an inequality of von Neumann and an application of the metric theory of tensor products to operators theory, J. Functional Analysis16(1974), 83–100
work page 1974
-
[32]
Johann von Neumann,Eine Spektraltheorie f¨ ur allgemeine Operatoren eines unit¨ aren Raumes, Math. Nachr.4(1951), 258–281. (Suman Mondal)School of Mathematics, Indian Institute of Science Education and Re- search Thiruvananthapuram, Kerala - 695551 Email address:suman2024@iisertvm.ac.in (Subhajit Palai)School of Mathematics, Indian Institute of Science Ed...
work page 1951
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