Commutator methods for the spectral analysis of time changes of horocycle flows
- Series
- CDSNS Colloquium
- Time
- Monday, February 23, 2015 - 11:00 for 1 hour (actually 50 minutes)
- Location
- Skiles 005
- Speaker
- Rafael Tiedra de Aldecoa – Pontificia Univ. Catolica de Chile
We show that all time changes of the horocycle flow on compact surfaces of
constant negative curvature have purely absolutely continuous spectrum in
the orthocomplement of the constant functions. This provides an answer to a
question of A. Katok and J.-P. Thouvenot on the spectral nature of time
changes of horocycle flows. Our proofs rely on positive commutator methods
for self-adjoint operators and the unique ergodicity of the horocycle flow.
www.mat.uc.cl/~rtiedra/download/Horocycles_Bordeaux_2014.pdf
<http://www.mat.uc.cl/%7Ertiedra/download/Horocycles_Bordeaux_2014.pdf
<http://www.mat.uc.cl/~rtiedra/download/Horocycles_Bordeaux_2014.pdf>>