TY - JOUR
T1 - Whitney–Hölder continuity of the SRB measure for transversal families of smooth unimodal maps
AU - Baladi, Viviane
AU - Benedicks, Michael
AU - Schnellmann, Daniel
PY - 2015/9/22
Y1 - 2015/9/22
N2 - We consider C2 families t ↦ft of C4 nondegenerate unimodal maps. We study the absolutely continuous invariant probability (SRB) measure μt of ft, as a function of t on the set of Collet–Eckmann (CE) parameters: Upper bounds: Assuming existence of a transversal CE parameter, we find a positive measure set of CE parameters Δ, and, for each t0∈Δ, a set Δ0⊂Δ of polynomially recurrent parameters containing t0 as a Lebesgue density point, and constants C≥1, >4Γ>4, so that, for every 1/2-Hölder function A, (Formula presented.). In addition, for all t∈Δ0, the renormalisation period Pt≤Pt0, and there are uniform bounds on the rates of mixing of (Formula presented.) for all t with Pt=Pt0. If ft(x)=tx(1-x), the set Δ contains almost all CE parameters. Lower bounds: Assuming existence of a transversal mixing Misiurewicz–Thurston parameter t0, we find a set of CE parameters ΔMT′ accumulating at t0, a constant C≥1, and a C∞ function A0, so that (Formula presented.).
AB - We consider C2 families t ↦ft of C4 nondegenerate unimodal maps. We study the absolutely continuous invariant probability (SRB) measure μt of ft, as a function of t on the set of Collet–Eckmann (CE) parameters: Upper bounds: Assuming existence of a transversal CE parameter, we find a positive measure set of CE parameters Δ, and, for each t0∈Δ, a set Δ0⊂Δ of polynomially recurrent parameters containing t0 as a Lebesgue density point, and constants C≥1, >4Γ>4, so that, for every 1/2-Hölder function A, (Formula presented.). In addition, for all t∈Δ0, the renormalisation period Pt≤Pt0, and there are uniform bounds on the rates of mixing of (Formula presented.) for all t with Pt=Pt0. If ft(x)=tx(1-x), the set Δ contains almost all CE parameters. Lower bounds: Assuming existence of a transversal mixing Misiurewicz–Thurston parameter t0, we find a set of CE parameters ΔMT′ accumulating at t0, a constant C≥1, and a C∞ function A0, so that (Formula presented.).
U2 - 10.1007/s00222-014-0554-8
DO - 10.1007/s00222-014-0554-8
M3 - Journal article
SN - 0020-9910
VL - 201
SP - 773
EP - 844
JO - Inventiones Mathematicae
JF - Inventiones Mathematicae
IS - 3
ER -