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Discrete Holomorphic Local Dynamical Systems

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Dynamics in Several Complex variables 197<br />

passes through as, has diameter ≤ εd −n/2 . By Theorem 1.54, f n admits an inverse<br />

branch defined on the ball Br and passing through as, with diameter ≤ d−n/2 .This<br />

implies the result.<br />

Proof of the claim. Let νl denote the mass of Rl ∧ [Δκ 2r ]. Then, ∑νl is the mass of<br />

R∧[Δ κ2r ]. Recall that this mass is smaller than ν. By definition, νld kl is the number<br />

of points in f l (Y ) ∩ Δκ 2r , counted with multiplicity. We only have to consider the<br />

case ν < 1. So, we have ν0 = 0andΔκ2rdoes not intersect Y, the critical values<br />

of f . It follows that Δκ 2r admits dk inverse branches for f . By definition of ν1,there<br />

are at most ν1dk such inverse branches which intersect Y, i.e. the images intersect Y .<br />

So, (1 − ν1)dk of them do not meet Y and the image of such a branch admits dk inverse branches for f . We conclude that Δκ 2r admits at least (1 − ν1)d2k inverse<br />

branches for f 2 . By induction, we construct for f n at least (1 − ν1 −···−νn−1)d kn<br />

inverse branches on Δκ 2r .<br />

Now, observe that the mass of ( f n )∗(ωFS)∧[Δκr] is exactly the area of f −n (Δκr).<br />

We know that it is smaller than Ad (k−1)n . It is not difficult to see that Δκ 2r has at<br />

most νd kn inverse branches with area ≥ Aν−1d −n . This completes the proof. �<br />

End of the proof of Theorem 1.45. Let a be a point out of the exceptional set E defined<br />

in Theorem 1.47 for X = Pk .Fixε > 0 and a constant α > 0 small enough. If<br />

μ ′ is a limit value of d−kn ( f n ) ∗ (δa), it is enough to show that �μ ′ − μ�≤2α + 2ε.<br />

Consider Z := {ν(R,z) > ε} and τ as in Proposition 1.50 for X = Pk .Wehave<br />

τ(a)=0. So, for r large enough we have τr(a) ≤ α. Consider all the negative orbits<br />

O j of order r j ≤ r<br />

�<br />

O j = a<br />

( j) j) j)<br />

−r ,...,a( j −1 ,a( 0<br />

( j) j) j)<br />

j)<br />

j)<br />

with f (a −i−1 )=a( −i and a(<br />

0 = a such that a( −r �∈Z and a(<br />

j −i ∈ Z for i �=r j. Each<br />

orbit is repeated according to its multiplicity. Let Sr denote the family of points<br />

b ∈ f −r (a) such that f i (b) ∈ Z for 0 ≤ i ≤ r. Thenf−r (a) \ Sr consists of the<br />

( j)<br />

preimages of the points a −r j . So, by definition of τr, wehave<br />

d −kr #Sr = τr(a) ≤ α<br />

and<br />

d k(r−r j) −kr −r<br />

= d #( f (a) \ Sr)=1 − τr(a) ≥ 1 − α.<br />

d −kr ∑ j<br />

We have for n ≥ r<br />

d −kn ( f n ) ∗ (δa)= d −kn ∑ ( f<br />

b∈Sr<br />

(n−r) ) ∗ (δb)+d −kn ∑( f<br />

j<br />

(n−r j) ∗<br />

)<br />

�<br />

� �<br />

δ ( j) .<br />

a −r j<br />

Since d −kn ( f n ) ∗ preserves the mass of any measure, the first term in the last sum<br />

is of mass d−kr #Sr = τr(a) ≤ α and the second term is of mass ≥ 1 − α. We apply<br />

( j)<br />

Proposition 1.51 to the Dirac masses at a<br />

of d −kn ( f n ) ∗ (δa) then<br />

−r j . We deduce that if μ′ is a limit value<br />

�μ ′ − μ�≤2α + 2ε.<br />

This completes the proof of the theorem. �

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