Marco Bruni
GGI Florence, October 2006
Energy cons. & effective
r
L
4.
Note that:
, thus
.
5.
Assume
and Taylor expand:
6.
6.
6.
Then:
a)
At O(1) in
D
r
and O(0) in
a
,
in any theory of gravity,
any P(
r
)
that admits an effective
r
L
behaves as
L
-CDM (
D
r
>0)
;
b)
For
a
> -1
r
->
r
L
, i.e.
r
L
is a de Sitter attractor.
ø
ø
From energy cons. -> Cosmic No-Hair for non-linear EoS.