Hostname: page-component-cd9895bd7-dk4vv Total loading time: 0 Render date: 2024-12-25T05:39:28.375Z Has data issue: false hasContentIssue false

Composite quasianalytic functions

Published online by Cambridge University Press:  17 August 2018

André Belotto da Silva
Affiliation:
Université Paul Sabatier, Institut de Mathématiques de Toulouse, 118 route de Narbonne, F-31062 Toulouse Cedex 9, France email [email protected]
Edward Bierstone
Affiliation:
University of Toronto, Department of Mathematics, 40 St. George Street, Toronto, ON, CanadaM5S 2E4 email [email protected]
Michael Chow
Affiliation:
University of Toronto, Department of Mathematics, 40 St. George Street, Toronto, ON, CanadaM5S 2E4 email [email protected]

Abstract

We prove two main results on Denjoy–Carleman classes: (1) a composite function theorem which asserts that a function $f(x)$ in a quasianalytic Denjoy–Carleman class ${\mathcal{Q}}_{M}$, which is formally composite with a generically submersive mapping $y=\unicode[STIX]{x1D711}(x)$ of class ${\mathcal{Q}}_{M}$, at a single given point in the source (or in the target) of $\unicode[STIX]{x1D711}$ can be written locally as $f=g\circ \unicode[STIX]{x1D711}$, where $g(y)$ belongs to a shifted Denjoy–Carleman class ${\mathcal{Q}}_{M^{(p)}}$; (2) a statement on a similar loss of regularity for functions definable in the $o$-minimal structure given by expansion of the real field by restricted functions of quasianalytic class ${\mathcal{Q}}_{M}$. Both results depend on an estimate for the regularity of a ${\mathcal{C}}^{\infty }$ solution $g$ of the equation $f=g\circ \unicode[STIX]{x1D711}$, with $f$ and $\unicode[STIX]{x1D711}$ as above. The composite function result depends also on a quasianalytic continuation theorem, which shows that the formal assumption at a given point in (1) propagates to a formal composition condition at every point in a neighbourhood.

Type
Research Article
Copyright
© The Authors 2018 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Belotto da Silva, A., Biborski, I. and Bierstone, E., Solutions of quasianalytic equations , Selecta Math. (N.S.) 23 (2017), 25232552.Google Scholar
Bierstone, E. and Milman, P. D., Semianalytic and subanalytic sets , Publ. Math. Inst. Hautes Études Sci. 67 (1988), 542.Google Scholar
Bierstone, E. and Milman, P. D., Canonical desingularization in characteristic zero by blowing up the maximum strata of a local invariant , Invent. Math. 128 (1997), 207302.Google Scholar
Bierstone, E. and Milman, P. D., Resolution of singularities in Denjoy–Carleman classes , Selecta Math. (N.S.) 10 (2004), 128.Google Scholar
Bierstone, E., Milman, P. D. and Valette, G., Arc-quasianalytic functions , Proc. Amer. Math. Soc. 143 (2015), 39153925.Google Scholar
Borel, E., Sur la généralisation du prolongement analytique , C. R. Math. Acad. Sci. Paris 130 (1900), 11151118.Google Scholar
Carleman, T., Les fonctions quasi-analytiques, Collection Borel (Gauthier-Villars, Paris, 1926).Google Scholar
Chaumat, J. and Chollet, A., Sur la division et la composition dans des classes ultradifférentiables , Studia Math. 136 (1999), 4970.Google Scholar
Denjoy, A., Sur les fonctions quasi-analytiques de variable reélle , C. R. Math. Acad. Sci. Paris 173 (1921), 13291331.Google Scholar
Glaeser, G., Fonctions composées différentiables , Ann. of Math. (2) 77 (1963), 193209.Google Scholar
Hadamard, J., Lectures on Cauchy’s problem in linear partial differential equations (Yale University Press, New Haven, 1923).Google Scholar
Hörmander, L., The analysis of linear partial differential operators I (Springer, Berlin–Heidelberg–New York, 1983).Google Scholar
Jaffe, E., Pathological phenomena in Denjoy–Carleman classes , Canad. J. Math. 68 (2016), 88108.Google Scholar
Komatsu, H., The implicit function theorem for ultradifferentiable mappings , Proc. Japan Acad. Ser. A Math. Sci. 55 (1979), 6972.Google Scholar
Malgrange, B., Frobenius avec singularités, 2. Le cas général , Invent. Math. 39 (1977), 6789.Google Scholar
Mandelbrojt, S., Séries Adhérentes, Régularisation des Suites, Applications, Collection Borel (Gauthiers-Villars, Paris, 1952).Google Scholar
Miller, C., Infinite differentiability in polynomially bounded o-minimal structures , Proc. Amer. Math. Soc. 123 (1995), 25512555.Google Scholar
Nowak, K. J., A note on Bierstone-Milman-Pawłucki’s paper ‘Composite differentiable functions’ , Ann. Polon. Math. 102 (2011), 293299.Google Scholar
Nowak, K. J., On division of quasianalytic function germs , Int. J. Math. 13 (2013), 15.Google Scholar
Nowak, K. J., Quantifier elimination in quasianalytic structures via non-standard analysis , Ann. Polon. Math. 114 (2015), 235267.Google Scholar
Rolin, J.-P., Speissegger, P. and Wilkie, A. J., Quasianalytic Denjoy–Carleman classes and o-minimality , J. Amer. Math. Soc. 16 (2003), 751777.Google Scholar
Roumieu, C., Ultradistributions définies sur ℝ n et sur certaines classes de variétés différentiables , J. Anal. Math. 10 (1962–63), 153192.Google Scholar
Thilliez, V., On quasianalytic local rings , Expo. Math. 26 (2008), 123.Google Scholar