On positive Rockland operators
Auscher, Pascal ; ter Elst, A. ; Robinson, Derek
Colloquium Mathematicae, Tome 67 (1994), p. 197-216 / Harvested from The Polish Digital Mathematics Library

Let G be a homogeneous Lie group with a left Haar measure dg and L the action of G as left translations on Lp(G;dg). Further, let H = dL(C) denote a homogeneous operator associated with L. If H is positive and hypoelliptic on L2 we prove that it is closed on each of the Lp-spaces, p ∈ 〈 1,∞〉, and that it generates a semigroup S with a smooth kernel K which, with its derivatives, satisfies Gaussian bounds. The semigroup is holomorphic in the open right half-plane on all the Lp-spaces, p ∈ [1,∞]. Further extensions of these results to nonhomogeneous operators and general representations are also given.

Publié le : 1994-01-01
EUDML-ID : urn:eudml:doc:210273
@article{bwmeta1.element.bwnjournal-article-cmv67i2p197bwm,
     author = {Pascal Auscher and A. ter Elst and Derek Robinson},
     title = {On positive Rockland operators},
     journal = {Colloquium Mathematicae},
     volume = {67},
     year = {1994},
     pages = {197-216},
     zbl = {0856.43005},
     language = {en},
     url = {http://dml.mathdoc.fr/item/bwmeta1.element.bwnjournal-article-cmv67i2p197bwm}
}
Auscher, Pascal; ter Elst, A.; Robinson, Derek. On positive Rockland operators. Colloquium Mathematicae, Tome 67 (1994) pp. 197-216. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-cmv67i2p197bwm/

[000] [Agm] S. Agmon, Lectures on Elliptic Boundary Value Problems, Van Nostrand Math. Stud. 2, van Nostrand, Princeton, 1965.

[001] [AMT] P. Auscher, A. McIntosh and Ph. Tchamitchian, Noyau de la chaleur d'opérateurs elliptiques complexes, Math. Research Letters 1 (1994), 37-45.

[002] [BrR1] O. Bratteli and D. W. Robinson, Operator Algebras and Quantum Statistical Mechanics, Vol. 1, 2nd ed., Springer, New York, 1987.

[003] [BrR2] O. Bratteli and D. W. Robinson, Subelliptic operators on Lie groups: variable coefficients, Acta Appl. Math. (1994), to appear.

[004] [BER] R. J. Burns, A. F. M. ter Elst and D. W. Robinson, Lp-regularity of subelliptic operators on Lie groups, J. Operator Theory 30 (1993), to appear.

[005] [Dzi] J. Dziubański, On semigroups generated by subelliptic operators on homogeneous groups, Colloq. Math. 64 (1993), 215-231. | Zbl 0837.43010

[006] [DHZ] J. Dziubański, W. Hebisch and J. Zienkiewicz, Note on semigroups generated by positive Rockland operators on graded homogeneous groups, Studia Math. 110 (1994), 115-126. | Zbl 0833.43009

[007] [ElR1] A. F. M. ter Elst and D. W. Robinson, Subcoercivity and subelliptic operators on Lie groups II: The general case, Potential Anal. (1994), to appear.

[008] [ElR2] A. F. M. ter Elst and D. W. Robinson, Subcoercive and subelliptic operators on Lie groups: variable coefficients, Publ. RIMS Kyoto Univ. 29 (1993), 745-801. | Zbl 0816.43002

[009] [ElR3] A. F. M. ter Elst and D. W. Robinson, Functional analysis of subelliptic operators on Lie groups, J. Operator Theory 30 (1993), to appear.

[010] [ElR4] A. F. M. ter Elst and D. W. Robinson, Weighted strongly elliptic operators on Lie groups, J. Funct. Anal. (1994), to appear.

[011] [FoS] G. B. Folland and Stein, Hardy Spaces on Homogeneous Groups, Math. Notes 28, Princeton University Press, Princeton, 1982. | Zbl 0508.42025

[012] [Heb] W. Hebisch, Sharp pointwise estimate for the kernels of the semigroup generated by sums of even powers of vector fields on homogeneous groups, Studia Math. 95 (1989), 93-106. | Zbl 0693.22005

[013] [HeS] W. Hebisch and A. Sikora, A smooth subadditive homogeneous norm on a homogeneous group, ibid. 96 (1990), 231-236.

[014] [HeN1] B. Helffer et J. Nourrigat, Caractérisation des opérateurs hypoelliptiques homogènes invariants à gauche sur un groupe de Lie nilpotent gradué, Comm. Partial Differential Equations 4 (1979), 899-958. | Zbl 0423.35040

[015] [HeN2] B. Helffer et J. Nourrigat, Hypoellipticité maximale pour des opérateurs polynômes de champs de vecteurs, Progr. Math. 58, Birkhäuser, Boston, 1985. | Zbl 0568.35003

[016] [Kat] T. Kato, Perturbation Theory for Linear Operators, 2nd ed., Grundlehren Math. Wiss. 132, Springer, Berlin, 1984.

[017] [Mil] K. G. Miller, Parametrices for hypoelliptic operators on step two nilpotent Lie groups, Comm. Partial Differential Equations 5 (1980), 1153-1184. | Zbl 0457.58019

[018] [NeS] E. Nelson and W. F. Stinespring, Representation of elliptic operators in an enveloping algebra, Amer. J. Math. 81 (1959), 547-560. | Zbl 0092.32103

[019] [Nir] L. Nirenberg, Remarks on strongly elliptic partial differential operators, Comm. Pure Appl. Math. 8 (1955), 649-675. | Zbl 0067.07602

[020] [Rob] D. W. Robinson, Elliptic Operators and Lie Groups, Oxford Math. Monographs, Oxford University Press, Oxford, 1991.

[021] [Roc] C. Rockland, Hypoellipticity for the Heisenberg group, Trans. Amer. Math. Soc. 240 (1978), 1-52. | Zbl 0326.22007

[022] [VSC] N. T. Varopoulos, L. Saloff-Coste and T. Coulhon, Analysis and Geometry on Groups, Cambridge Tracts in Math. 100, Cambridge University Press, Cambridge, 1992.