INVARIANT MEASURE OF CRITICAL CIRCLE HOMEOMORPHISMS WITH COUNTABLE NUMBER OF BREAKS
Keywords:
circle homeomorphism, rotation number, invariant measure, critical point, break point.Abstract
It is proved that invariant measures of P -homeomorphisms of a circle with countable
many break points and with single critical point, and an irrational rotation number are
singular with respect to the Lebesgue measure on the circle.
References
A. Denjoy: Sur les courbes de nies par les equations di erentielles a la surface du tore.
J. Math. Pures Appl., 11, 333-375 (1932).
Y. Katznelson and D. Ornstein: The absolute continuity of the conjugation of certain
di eomorphisms of the circle. Ergod. Theor. Dyn. Syst., 9, 681-690, (1989).
K.M. Khanin and Ya.G. Sinai: Smoothness of conjugacies of di eomorphisms of the
circle with rotations. Russ. Math. Surv., 44, 69-99, (1989), translation of Usp. Mat.
Nauk, 44, 57-82, (1989).
M. Herman: Sur la conjugaison di erentiable des di eomorphismes du cercle a des
rotations. Inst. Hautes Etudes Sci. Publ. Math., 49, 225-234 (1979).
A.A. Dzhalilov and K.M. Khanin: On invariant measure for homeomorphisms of a
circle with a point of break., Funct. Anal. Appl., 32, (3) 153-161 (1998).
A.A. Dzhalilov and I. Liousse: Circle homeomorphisms with two break points. Nonlin-
earity, 19, 1951-1968 (2006).
A.A. Dzhalilov, I. Liousse and D. Mayer: Singular measures of piecewise smooth circle
homeomorphisms with two break points. Discrete and continuous dynamical systems,
, (2), 381-403 (2009).
A.A. Dzhalilov, D. Mayer and U.A. Safarov: Piecwise-smooth circle homeomorphisms
with several break points. Izvestiya RAN: Ser. Mat. 76:1, 95-113, translation of
Izvestiya: Mathematics 76:1, 95-113, (2012).
Teplinsky A.: A circle di eomorphism with breaks that is absolutely continuously
linearizable. Ergodic Theory and Dynamical Systems, 38, N1, 371{383, (2018).
J. Graczyk, G. Swiatek.: Singular measure in circle dynamics. Commun. Math. Phys.
, 213-230, (1993).
P. Guarino, E. de Faria: There are no - nite absolutely continuous invariant mea-
sures for multicritical circle maps. Nonlinearity, 34, N10, 6727{351, (2021).
U.A. Safarov: Invariant measure of circle maps with mixed type of singularities.
Izvestiya vuzov, Mathematics, N7, 71{84, (2023).